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In vivo activity of terpinen-4-ol, the main bioactive component of Melaleuca alternifolia Cheel (tea tree) oil against azole-susceptible and -resistant human pathogenic Candida species
Mondello, Francesca; De Bernardis, Flavia; Girolamo, Antonietta; Cassone, Antonio; Salvatore, Giuseppe
Background Recent investigations on the antifungal properties of essential oil of Melaleuca alternifolia Cheel (Tea Tree Oil, TTO) have been performed with reference to the treatment of vaginal candidiasis. However, there is a lack of in vivo data supporting in vitro results, especially regarding the antifungal properties of TTO constituents. Thus, the aim of our study was to investigate the in vitro and the in vivo anti-Candida activity of two critical bioactive constituents of TTO, terpinen-4-ol and 1,8-cineole. Methods Oophorectomized, pseudoestrus rats under estrogen treatment were used for experimental vaginal infection with azole (fluconazole, itraconazole) -susceptible or -resistant strains of C. albicans. All these strains were preliminarily tested for in vitro susceptibility to TTO, terpinen-4-ol and 1,8-cineole for their antifungal properties, using a modification of the CLSI (formerly NCCLS) reference M27-A2 broth micro-dilution method. Results In vitro minimal inhibitory concentrations (MIC90) values were 0.06% (volume/volume) for terpinen-4-ol and 4% (volume/volume) for 1,8-cineole, regardless of susceptibility or resistance of the strains to fluconazole and itraconazole. Fungicidal concentrations of terpinen-4-ol were equivalent to the candidastatic activity. In the rat vaginal infection model, terpinen-4-ol was as active as TTO in accelerating clearance from the vagina of all Candida strains examined. Conclusion Our data suggest that terpinen-4-ol is a likely mediator of the in vitro and in vivo activity of TTO. This is the first in vivo demonstration that terpinen-4-ol could control C. albicans vaginal infections. The purified compound holds promise for the treatment of vaginal candidiasis, and particularly the azole-resistant forms. PMID:17083732
Technology Transfer Automated Retrieval System (TEKTRAN)
The essential oil from Melaleuca alternifolia has been used for pharmaceutical and household products and as an antiseptic treatment for human ailments. Growing public concern over the use of synthetic pesticides emphasizes the need for alternative treatments. Our work tests the effectiveness of m...
Antimicrobial effect of Melaleuca alternifolia dental gel in orthodontic patients.
Santamaria, Milton; Petermann, Klodyne Dayana; Vedovello, Silvia Amélia Scudeler; Degan, Viviane; Lucato, Adriana; Franzini, Cristina Maria
The aim of this study was to evaluate the antimicrobial effect and sensorial analysis of the gel developed with the essential oil of Melaleuca alternifolia. Thirty-four volunteers, divided into 2 groups, were monitored for 4 weeks. Initially, clinical biofilm (plaque index) and saliva samples (bacteria count) were collected, from which the standard values for each patient were obtained. For 7 days, group 1 used the melaleuca gel (Petite Marie/All Chemistry, São Paulo, Brazil), and group 2 used Colgate Total (S.B. Campo, São Paulo, Brazil). After 7 days, the plaque index was performed again, as well as the bacteria count and the sensorial analysis (appearance, color, odor, brightness, viscosity, and first taste sensation). The volunteers were instructed to return to their usual dental hygiene habits for 15 days. After this, group 1 started using Colgate Total, and group 2 started using the melaleuca gel, with the same evaluation procedures as the first week. The data were analyzed statistically with a significance level of 5%. In the bacteria count and clinical disclosure, the melaleuca gel was more effective in decreasing the dental biofilm and the numbers of bacteria colonies. According to the data from the sensory evaluation, Colgate Total (the control) showed better results regarding flavor and first sensation (P <0.05). We concluded that melaleuca gel is efficient in bacteria control but needs improvement in taste and first sensation. PMID:24485734
Potential anti-inflammatory effects of Melaleuca alternifolia essential oil on human peripheral blood leukocytes.
Caldefie-Chézet, F; Fusillier, C; Jarde, T; Laroye, H; Damez, M; Vasson, M-P; Guillot, J
The fungicidal and bactericidal actions of the essential oil (EO) of Melaleuca alternifolia seem well established, but their anti-inflammatory and antioxidative effects remain unclear. This study investigated in vitro the possible role of whole Melaleuca alternifolia EO as a modulator of the inflammatory/non-specific immune response by exploring the chemotaxis and kinetic radical oxygen species (ROS) production of leukocytes and cytokine secretion in peripheral blood mononuclear cells (PBMCs) in humans. The influence of Melaleuca alternifolia EO on the chemotaxis under agarose of isolated neutrophils (PMNs) was evaluated. The kinetics of ROS production by stimulated total circulating leukocytes was followed over 2 h by recording the fluorescence intensity of oxidized dihydrorhodamine 123. The effects of this EO on pro-(interleukin IL-2) and anti-(IL-4 and IL10) inflammatory cytokine secretions were determined by ELISA following incubation of PBMCs with the EO for 24 h. Melaleuca alternifolia EO was inefficient on the chemotaxis of PMNs. It exerted an antioxidant effect, reducing ROS production throughout the kinetic study. Melaleuca alternifolia EO inhibited PBMC proliferation, as revealed by a reduction in IL-2 secretion by stimulated lymphocytes. This EO at 0.1% directly increased the secretion of the anti-inflammatory cytokine IL-4 compared with IL-4 secretion without EO (18.5 +/- 10.0 vs 3.3 +/- 1, p < 0.05), and also increased IL-10 secretion at 0.01% (94.9 +/- 38.7 vs 44.1 +/- 18, ns). Melaleuca alternifolia EO may not only act as an anti-inflammatory mediator through its antioxidant activity but may also efficiently protect the organism by reducing the proliferation of inflammatory cells without affecting their capacity to secrete anti-inflammatory cytokines. PMID:16619364
Activity of Tea Tree (Melaleuca alternifolia) Essential Oil against L3 Larvae of Anisakis simplex
Langa, Elisa; Murillo, Paula
Nematicidal activity of Melaleuca alternifolia essential oil, commonly known as tea tree oil (TTO), was assayed in vitro against L3 larvae of Anisakis simplex. The results showed a mortality of 100% for concentrations between 7 and 10 μL/mL after 48 h of incubation, obtaining an LD50 value of 4.53 μL/mL after 24 hours and 4.27 μL/mL after 48 hours. Concentration-dependent inhibition of acetylcholinesterase was observed for tea tree essential oil showing inhibition values of 100% at 100 μL/mL. This fact suggests that TTO may act as an AChE inhibitor. Terpinen-4-ol was discarded as main larvicide compound as it did not show larvicidal or anticholinesterase activity. The data obtained suggest that the essential oil of Melaleuca alternifolia may have a great therapeutic potential for the treatment of human anisakiasis. PMID:24967378
Treatment of toenail onychomycosis with 2% butenafine and 5% Melaleuca alternifolia (tea tree) oil in cream.
Syed, T A; Qureshi, Z A; Ali, S M; Ahmad, S; Ahmad, S A
The prevalence of onychomycosis, a superficial fungal infection that destroys the entire nail unit, is rising, with no satisfactory cure. The objective of this randomized, double-blind, placebo-controlled study was to examine the clinical efficacy and tolerability of 2% butenafine hydrochloride and 5% Melaleuca alternifolia oil incorporated in a cream to manage toenail onychomycosis in a cohort. Sixty outpatients (39 M, 21 F) aged 18-80 years (mean 29.6) with 6-36 months duration of disease were randomized to two groups (40 and 20), active and placebo. After 16 weeks, 80% of patients using medicated cream were cured, as opposed to none in the placebo group. Four patients in the active treatment group experienced subjective mild inflammation without discontinuing treatment. During follow-up, no relapse occurred in cured patients and no improvement was seen in medication-resistant and placebo participants. PMID:10357864
Essential oils to control ichthyophthiriasis in pacu, Piaractus mesopotamicus (Holmberg): special emphasis on treatment with Melaleuca alternifolia.
Valladão, G M R; Gallani, S U; Ikefuti, C V; da Cruz, C; Levy-Pereira, N; Rodrigues, M V N; Pilarski, F
In vitro effect of the Melaleuca alternifolia, Lavandula angustifolia and Mentha piperita essential oils (EOs) against Ichthyophthirius multifiliis and in vivo effect of M. alternifolia for treating ichthyophthiriasis in one of the most important South American fish, Piaractus mesopotamicus (Holmberg), were evaluated. The in vitro test consisted of three EOs, each at concentrations of 57 μL L(-1) , 114 μL L (-1) , 227 μL L(-1) and 455 μL L (-1) , which were assessed once an hour for 4 h in microtitre plates (96 wells). The in vitro results demonstrated that all tested EOs showed a cytotoxic effect against I. multifiliis compared to control groups (P < 0.05). The in vivo treatment for white spot disease was performed in a bath for 2 h day(-1) for 5 days using the M. alternifolia EO (50 μL L (-1) ). In this study, 53.33% of the fish severely infected by I. multifiliis survived after the treatment with M. alternifolia (50 μL L (-1) ) and the parasitological analysis has shown an efficacy of nearly 100% in the skin and gills, while all the fish in the control group died. Furthermore, the potential positive effect of M. alternifolia EO against two emergent opportunistic bacteria in South America Edwardsiella tarda and Citrobacter freundii was discussed. PMID:26776242
Melaleuca alternifolia concentrate inhibits in vitro entry of influenza virus into host cells.
Li, Xinghua; Duan, Songwei; Chu, Cordia; Xu, Jun; Zeng, Gucheng; Lam, Alfred King-Yin; Zhou, Junmei; Yin, Yue; Fang, Danyun; Reynolds, Maxwell John; Gu, Huaiyu; Jiang, Lifang
Influenza virus causes high morbidity among the infected population annually and occasionally the spread of pandemics. Melaleuca alternifolia Concentrate (MAC) is an essential oil derived from a native Australian tea tree. Our aim was to investigate whether MAC has any in vitro inhibitory effect on influenza virus infection and what mechanism does the MAC use to fight the virus infection. In this study, the antiviral activity of MAC was examined by its inhibition of cytopathic effects. In silico prediction was performed to evaluate the interaction between MAC and the viral haemagglutinin. We found that when the influenza virus was incubated with 0.010% MAC for one hour, no cytopathic effect on MDCK cells was found after the virus infection and no immunofluorescence signal was detected in the host cells. Electron microscopy showed that the virus treated with MAC retained its structural integrity. By computational simulations, we found that terpinen-4-ol, which is the major bioactive component of MAC, could combine with the membrane fusion site of haemagglutinin. Thus, we proved that MAC could prevent influenza virus from entering the host cells by disturbing the normal viral membrane fusion procedure. PMID:23966077
Bioactivity of tea tree oil from Melaleuca alternifolia against sheep lice (Bovicola ovis Schrank) in vitro.
James, P J; Callander, J T
Tea tree oil (TTO) from the Australian native plant Melaleuca alternifolia has wide ranging bio-active properties, including insecticidal and repellent activity against arthropods. Furthermore, composition of commercially available Australian TTO is specified under an International Organization for Standardization standard (ISO 4730), reducing the potential for variable effects often noted with botanical pesticides. The effect of TTO, meeting the ISO standard for terpinen-4-ol chemotype, was tested against sheep lice (Bovicola ovis Schrank) in a series of laboratory studies. Immersion of wool for 60s in formulations containing concentrations of 1% TTO and above caused 100% mortality of adult lice and eggs. Exposure to vapours from TTO, delivered as droplets in fumigation chambers and when applied to wool also caused high mortality in both lice and eggs. The main active component of TTO in the fumigant tests was terpinen-4-ol. Treated surface assays and tests with wool where the formulation was allowed to dry before exposure of lice indicated low persistence. These studies demonstrate that TTO is highly toxic to sheep lice and active at concentrations that suggest potential for the development of TTO-based ovine lousicides. PMID:22398149
In Vitro Susceptibility of Pythium insidiosum to Melaleuca alternifolia, Mentha piperita and Origanum vulgare Essential Oils Combinations.
de Souza Silveira Valente, Júlia; de Oliveira da Silva Fonseca, Anelise; Denardi, Laura Bedin; Dal Ben, Vanessa Silveira; de Souza Maia Filho, Fernando; Baptista, Cristiane Telles; Braga, Caroline Quintana; Zambrano, Cristina Gomes; Alves, Sydney Hartz; de Avila Botton, Sônia; Pereira, Daniela Isabel Brayer
Pythium insidiosum is the etiologic agent of pythiosis, a severe and emerging disease that affects mammals. Failure of conventional antifungal therapies is partially justified by the absence of ergosterol in the plasma membrane of this oomycete. Despite research advancement, the treatment of pythiosis has not been not fully established. The present study investigated the in vitro susceptibility profile of Brazilian isolates of P. insidiosum (n = 20) against Melaleuca alternifolia, Mentha piperita and Origanum vulgare essential oils, and their combinations. Susceptibility tests were performed according to CLSI M38-A2 protocol, and combinations were evaluated by the microdilution cherkerboard method. All tested essential oils showed antimicrobial activity against P. insidiosum, and the greatest activity of O. vulgare was highlighted. Synergistic and/or indifferent effect was observed for all combinations evaluated, especially the M. piperita and O. vulgare combination, which showed 65 % synergism. This is the first study to report in vitro combinations of essential oils against P. insidiosum indicating the susceptibility of this oomycete to M. alternifolia, M. piperita and O. vulgare essential oils, as well as their combinations. PMID:27209011
Melaleuca alternifolia (Tea Tree) Oil: a Review of Antimicrobial and Other Medicinal Properties
Carson, C. F.; Hammer, K. A.; Riley, T. V.
Complementary and alternative medicines such as tea tree (melaleuca) oil have become increasingly popular in recent decades. This essential oil has been used for almost 100 years in Australia but is now available worldwide both as neat oil and as an active component in an array of products. The primary uses of tea tree oil have historically capitalized on the antiseptic and anti-inflammatory actions of the oil. This review summarizes recent developments in our understanding of the antimicrobial and anti-inflammatory activities of the oil and its components, as well as clinical efficacy. Specific mechanisms of antimicrobial and anti-inflammatory action are reviewed, and the toxicity of the oil is briefly discussed. PMID:16418522
In vitro repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) oils on Haemotobia irritans and Chrysomya megacephala flies.
Klauck, V; Pazinato, R; Radavelli, W M; Volpato, A; Stefani, L M; Santos, R C V; Vaucher, R A; Boligon, A A; Athayde, M L; Da Silva, A S
This study aimed to evaluate the repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) essential oils on two species of flies (Haemotobia irritans and Chrysomya megacephala). For the in vitro studies, free-living adult flies were captured and reared in the laboratory. To verify the repellency effect, an apparatus was constructed where H. irritans and C. megacephala were exposed to andiroba and tea tree oils (5.0%), as well as to a known repellent (citronella, 5.0%) to validate the test. The study demonstrated that all three oils used showed in vitro repellent effect against both species of flies. It is possible to conclude that the essential oils (tea tree and andiroba) have repellent effect on these species of flies used in this study. PMID:25801266
In vitro activity of essential oils of free and nanostructured Melaleuca alternifolia and of terpinen-4-ol on eggs and larvae of Haemonchus contortus.
Grando, T H; de Sá, M F; Baldissera, M D; Oliveira, C B; de Souza, M E; Raffin, R P; Santos, R C V; Domingues, R; Minho, A P; Leal, M L R; Monteiro, S G
Haemonchus contortus is one of the major gastrointestinal nematodes responsible for significant economic and production losses of sheep. Diseases caused by this species lack effective anthelmintic products, and the search for new compounds to replace synthetic anthelmintics has been extensive. The present investigation assesses the in vitro activity of the essential oil of melaleuca (Melaleuca alternifolia), both free (TTO) and nanostructured (nanoTTO), and terpinen-4-ol (terp-4-ol) on eggs and larvae of H. contortus. Tests of egg hatching (EHT) and inhibition of larval migration (LMIT) were used to assess the in vitro efficacy of TTO, nanoTTO and terp-4-ol. Using EHT, at a concentration of 3.5 mg/ml, 100% inhibition occurred using TTO and terp-4-ol, with LC50 values of 0.43 and 0.63 mg/ml, and LC90 values of 1.75 mg/ml and 3.12 mg/ml, respectively. NanoTTO had lower activity, with 82.6% inhibition at the same concentration. Using LMIT, TTO and nanoTTO had a similar activity with 88.0% and 84.8% inhibition, respectively, at a concentration of 56 mg/ml. Terp-4-ol had a greater effect on larvae, with 85.7% inhibition at a concentration of 56 mg/ml and 82.4% at 3.5 mg/ml, demonstrating high activity at the lowest concentration tested. Therefore, the results indicate that all substances tested showed ovicidal and larvicidal activity against H. contortus. TTO, terp-4-ol and, mainly, nanoTTO may be targeted in in vivo studies, besides being a promising line of research into the control and treatment of veterinary important helminths. PMID:26096177
Mechanism of Action of Melaleuca alternifolia (Tea Tree) Oil on Staphylococcus aureus Determined by Time-Kill, Lysis, Leakage, and Salt Tolerance Assays and Electron Microscopy
Carson, Christine F.; Mee, Brian J.; Riley, Thomas V.
The essential oil of Melaleuca alternifolia (tea tree) has broad-spectrum antimicrobial activity. The mechanisms of action of tea tree oil and three of its components, 1,8-cineole, terpinen-4-ol, and α-terpineol, against Staphylococcus aureus ATCC 9144 were investigated. Treatment with these agents at their MICs and two times their MICs, particularly treatment with terpinen-4-ol and α-terpineol, reduced the viability of S. aureus. None of the agents caused lysis, as determined by measurement of the optical density at 620 nm, although cells became disproportionately sensitive to subsequent autolysis. Loss of 260-nm-absorbing material occurred after treatment with concentrations equivalent to the MIC, particularly after treatment with 1,8-cineole and α-terpineol. S. aureus organisms treated with tea tree oil or its components at the MIC or two times the MIC showed a significant loss of tolerance to NaCl. When the agents were tested at one-half the MIC, only 1,8-cineole significantly reduced the tolerance of S. aureus to NaCl. Electron microscopy of terpinen-4-ol-treated cells showed the formation of mesosomes and the loss of cytoplasmic contents. The predisposition to lysis, the loss of 260-nm-absorbing material, the loss of tolerance to NaCl, and the altered morphology seen by electron microscopy all suggest that tea tree oil and its components compromise the cytoplasmic membrane. PMID:12019108
Repellent effects of Melaleuca alternifolia (tea tree) oil against cattle tick larvae (Rhipicephalus australis) when formulated as emulsions and in β-cyclodextrin inclusion complexes.
Yim, Wei Tsun; Bhandari, Bhesh; Jackson, Louise; James, Peter
Rhipicephalus australis (formerly Boophilus microplus) is a one host tick responsible for major economic loss in tropical and subtropical cattle production enterprises. Control is largely dependent on the application of acaricides but resistance has developed to most currently registered chemical groups. Repellent compounds that prevent initial attachment of tick larvae offer a potential alternative to control with chemical toxicants. The repellent effects of Melaleuca alternifolia oil (TTO) emulsions and two β-cyclodextrin complex formulations, a slow release form (SR) and a modified faster release form (FR), were examined in a series of laboratory studies. Emulsions containing 4% and 5% TTO applied to cattle hair in laboratory studies completely repelled ascending tick larvae for 24h whereas 2% and 3% formulations provided 80% protection. At 48h, 5% TTO provided 78% repellency but lower concentrations repelled less than 60% of larvae. In a study conducted over 15 days, 3% TTO emulsion applied to cattle hair provided close to 100% repellency for 2 days, but then protection fell to 23% by day 15. The FR formulation gave significantly greater repellency than the emulsion and the SR formulation from day 3 until the end of the study (P<0.05), providing almost complete repellency at day 3 (99.5%), then decreasing over the period of the study to 49% repellency at day 15. Proof of concept is established for the use of appropriately designed controlled-release formulations to extend the period of repellency provided by TTO against R. australis larvae. PMID:27369582
Comparative evaluation of co-enzyme Q10 and Melaleuca alternifolia as antioxidant gels in treatment of chronic periodontitis: A clinical study
Raut, Chetan Purushottam; Sethi, Kunal S.
Background: Conventional nonsurgical periodontal therapy has been proven to be an effective treatment for patients with chronic periodontitis. Coenzyme Q10 and tea tree oil (TTO) are known to have potential therapeutic benefits in chronic periodontitis. Aims: The aim of the study is to compare the efficacy of Coenzyme Q10 (Perio Q®) and tea tree oil (Melaleuca alternifolia) gel as an adjunct to scaling and root planing in the treatment of chronic periodontitis. Materials and Methods: Patients were divided equally into three groups: Group I (Control group): those receiving placebo gel + SRP, Group II (Test group I): those receiving Perio QTM gel + SRP, and Group III (Test group II): those receiving tea tree oil gel + SRP. A total of 15 patients with 45 sites were enrolled in the study. Clinical parameters evaluated were plaque index (PI), gingival bleeding index (GI), probing pocket depth (PPD), and clinical attachment level (CAL). Statistical Analysis Used: Paired t-test was applied using SPSS software. Results: Mean PPD reduction for Group I, Group II, and Group III was 0.50 ± 0.2, 2.95 ± 0.20, and 2.09 ± 0.15, respectively. Mean CAL reduction for Group I, Group II, and Group III was 0.45 ± 0.22, 2.33 ± 0.04, and 2.28 ± 0.09, respectively. Changes in mean PI scores for Group I, Group II, and Group III were 0.67 ± 017, 1.00 ± 0.11, and 1.08 ± 0.05 and GBI scores were 0.92 ± 0.29, 1.08 ± 0.13, and 0.88 ± 0.28, respectively. Conclusions: Coenzyme Q10 and tea tree oil gel proved to be effective in the treatment of chronic periodontitis.
In vivo bactericidal effect of Melaleuca alternifolia essential oil against Aeromonas hydrophila: Silver catfish (Rhamdia quelen) as an experimental model.
F Souza, Carine; Baldissera, Matheus D; A Vaucher, Rodrigo; Lopes, Leonardo Q S; Vizzotto, Bruno S; Raffin, Renata P; Santos, Roberto C V; L da Veiga, Marcelo; U M da Rocha, Maria Izabel; Stefani, Lenita M; Baldisserotto, Bernardo
Aeromonas hydrophila is one of the main causative agent of high mortality and significative economic losses in aquaculture and has become increasingly resistant to conventional antibiotics. One feasible alternative to control and treat it is the use of essential oils. This study aimed to evaluate A. hydrophila susceptibility to tea tree oil (TTO-Melaleuca alternifolia) in vivo, and the effect of this treatment. In vivo tests were performed using silver catfish (Rhamdia quelen) as the experimental model. Silver catfish were treated with TTO at 25 and 50 μL/L for seven days before infection. After seven days, the fish were inoculated with A. hydrophila via intramuscularly. Treatment with TTO at 50 μL/L was able to extend longevity of infected fish, and showed 88% of therapeutic success, even though it did not show curative efficacy. TTO treatment was not toxic under these tested concentrations, since biomarkers of hepatic and renal functions were not affected, and the concentration of 50 μL/L was able to prevent increased levels of aspartate aminotransferase. There was no significative differences regarding hematological parameters (p < 0.05). Treatment with TTO 50 μL/L was able to reduce histopathological alterations usually caused by this type of bacteria in the gills, but it was unable to reduce hepatic histopathological alterations. Our results showed, for the first time, that TTO has high activity against A. hydrophila and proved to be a natural alternative to prevent and control this pathogen. PMID:27392700
Effects of Terpene Chemotypes of Melaleuca alternifolia on Two Specialist Leaf Beetles and Susceptibility to Myrtle Rust.
Bustos-Segura, Carlos; Külheim, Carsten; Foley, William
Plant chemical polymorphisms, or plant chemotypes, are characterized by intraspecific discrete differences of plant secondary metabolites in the same plant tissue. Chemotypes that differ in foliar terpene composition are found commonly in Myrtaceae. In this study, we focused on terpene chemotypes of medicinal tea tree, Melalecua alternifolia, to explore whether this variation affects two specialist herbivores Paropsisterna tigrina and Faex sp. (Coleoptera: Chrysomelidae), and if this could explain the maintenance of this variation. We tested whether insect performance, oviposition preference, and plant damage were associated with different chemotypes. We found that larval growth rate of Faex sp. was higher in chemotypes with high concentrations of 1,8-cineole, and that oviposition preference depended on the chemotype of the larval diet. Although performance traits and preference for oviposition of P. tigrina did not vary among chemotypes, adults inflicted less damage on plants with a high concentration of terpinolene. Additionally, we tested whether different chemotypes showed different levels of susceptibility by myrtle rust (Puccinia psidii). We found that plants with a high concentration of 1,8-cineole were more likely to be infected under controlled conditions. Although there is evidence that terpene chemotypes are a mediator of the interaction with natural enemies, the most detrimental pest of this plant, P. tigrina, does not seem to be affected by variation in plant terpenes. PMID:26385229
Technology Transfer Automated Retrieval System (TEKTRAN)
This book chapter is intended to provide an overview of the Australian tree Melaleuca quinquenervia, its general biology, invasive ecology in southern Florida and biological control. Specific reference is given to the invasion of melaleuca into freshwater herbaceous marsh communities in Florida, whi...
In Vitro Activities of Ketoconazole, Econazole, Miconazole, and Melaleuca alternifolia (Tea Tree) Oil against Malassezia Species
Hammer, K. A.; Carson, C. F.; Riley, T. V.
The in vitro activities of ketoconazole, econazole, miconazole, and tea tree oil against 54 Malassezia isolates were determined by agar and broth dilution methods. Ketoconazole was more active than both econazole and miconazole, which showed very similar activities. M. furfur was the least susceptible species. M. sympodialis, M. slooffiae, M. globosa, and M. obtusa showed similar susceptibilities to the four agents. PMID:10639388
Hard Evidence for Melaleuca Biocontrol
Technology Transfer Automated Retrieval System (TEKTRAN)
The population dynamics of a cohort of Melaleuca quinquenervia were monitored over a 5-y period in a cypress-pine wetland while subjected to two levels of herbivory. The trees were recruited during 1998-1999 after a destructive crown fire. Half of 26 experimental plots were sprayed every 4-6 weeks...
Natural enemies thin melaleuca-canopy and help increase plant diversity in the melaleuca stands.
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian tree Melaleuca quinquenervia (Cav.) S.T. Blake (melaleuca) formed dense monocultural forests several decades after invading Florida and the Caribbean islands. These dominant forests have displaced native vegetation in sensitive wetland systems. We assumed that native plant diversity...
Establishment, spread and impacts of Boreioglycaspis melaleucae, a biological control agent of the invasive tree Melaleuca quinquenervia.
Technology Transfer Automated Retrieval System (TEKTRAN)
We report the establishment and preliminary impacts of the melaleuca psyllid (Boreioglycaspis melaleucae Moore). Initially, eight sites were inoculated with 7000-10000 adult psyllids, with one exception where 2000 nymphs were released on seedlings. Psyllid populations established everywhere irrespe...
Ng, Wen-jie; Lim, Mei-siew
Honey is well-known for its antioxidant properties due to the presence of phytochemical compounds, which are also involved in antibacterial activities. In this study, properties (total phenolic compounds, flavonoids, free radical scavenging activity, ferric reducing-antioxidant power, reducing sugar content, and pH) of Malaysian Melaleuca honey were investigated for their antistaphylococcal activity, against both methicillin-sensitive (MSSA) and resistant (MRSA) Staphylococcus aureus strains using a hole-in-plate diffusion method. The outcome revealed there is a significant positive correlation between the antistaphylococcal activity and increase in honey concentration [20%-80% (v/v) in distilled water], which also correlated with each of the above mentioned parameter in honey, except for pH value that shows negative correlation. Furthermore, there was no difference in susceptibility to Melaleuca honey between MSSA and MRSA strains. Thus, in addition to being an antioxidant product, Melaleuca honey has a potential as a natural antistaphylococcal agent. PMID:26521521
A clinical study: Melaleuca, Manuka, Calendula and green tea mouth rinse.
Lauten, Jeffrey D; Boyd, Linda; Hanson, M Blair; Lillie, Dana; Gullion, Christina; Madden, Theresa E
A novel mouthrinse (IND 61,164) containing essential oils and extracts from four plant species (Melaleuca alternifolia, Leptospermum scoparium, Calendula officinalis and Camellia sinensis) were tested. This study aimed to evaluate the safety, palatability and preliminary efficacy of the rinse. Fifteen subjects completed the Phase I safety study. Seventeen subjects completed the Phase II randomized placebo-controlled study. Plaque was collected, gingival and plaque indices were recorded (baseline, 6 weeks, and 12 weeks). The relative abundance of two periodontal pathogens (Actinobacillus actinomycetemcomitans, Tanerella forsythensis) was determined utilizing digoxigenin-labeled DNA probes. ANCOVA was used at the p = 0.05 level of significance. Two subjects reported a minor adverse event. One subject withdrew from the study. Several subjects objected to the taste of the test rinse but continued treatment. Differences between gingival index, plaque index or relative abundance of either bacterial species did not reach statistical significance when comparing nine placebo subjects with eight test rinse subjects. Subjects exposed to the test rinse experienced no abnormal oral lesions, altered vital signs, changes in liver, kidney, or bone marrow function. Larger scale studies would be necessary to determine the efficacy and oral health benefits of the test rinse. PMID:16317652
Cutting line determination for plant propagation
NASA Astrophysics Data System (ADS)
Lo, Li-Yun; Hsia, Chi-Chun; Sun, Hua-Hong; Chen, Hsiang-Ju; Wu, Xin-Ting; Hu, Min-Chun
Investigating an efficient method for plant propagation can help not only prevent extinction of plants but also facilitate the development of botanical industries. In this paper, we propose to use image processing techniques to determine the cutting-line for the propagation of two kinds of plants, i.e. Melaleuca alternifolia Cheel and Cinnamomum kanehirai Hay, which have quite different characteristics in terms of shape, structure, and propagation way (e.g. propagation by seeding and rooting, respectively). The proposed cutting line determination methods can be further applied to develop an automatic control system to reduce labor cost and increase the effectiveness of plant propagation.
First report of the biological control agent Boreioglycaspis melaleucae (Hemiptera: Psyllidae) in California, USA.
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian psyllid Boreioglycaspis melaleucae is a specialized herbivore of Melaleuca quinquenervia and other closely related congeners. Boreioglycaspis melaleucae was discovered in Los Angeles County (California, USA) in late 2009, feeding on ornamentally planted M. quinquenervia trees. The ps...
Ultrastructure of wax-producing structures on the integument of the melaleuca psyllid Boreioglycaspis melaleucae (Hemiptera: Psyllidae) and honeydew excretion behavior in males and females
Technology Transfer Automated Retrieval System (TEKTRAN)
The melaleuca psyllid, Boreioglycaspis melaleucae (Hemiptera: Psyllidae), was introduced to Florida as a biological control agent against Melaleuca quinquenervia, an invasive evergreen tree that has invaded large areas of Florida Everglades. Colonies of B. melaleucae nymphs are normally covered by w...
Successful biological control of Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia is native to north-eastern Australia, parts of New Guinea, and New Caledonia. It has been present in south Florida since the late ninteenth century (Dray et al. 2006) and dispersal was assisted by nurserymen who are believed to have deliberately spread seeds into natural area...
Technology Transfer Automated Retrieval System (TEKTRAN)
The adventive Australian tree Melaleuca quinquenervia (Cav.) S.T. Blake is an invasive pest plant in the greater Everglades region of Florida. Public agencies and organizations responsible for natural areas management have developed effective chemical and mechanical strategies for treating infestati...
The Influence of Tea Tree Oil (Melaleuca alternifolia) on Fluconazole Activity against Fluconazole-Resistant Candida albicans Strains
Garbusińska, Aleksandra; Kowalska, Magdalena; Król, Wojciech
The aim of this study was to evaluate the activity of fluconazole against 32 clinical strains of fluconazole-resistant Candida albicans, and C. albicans ATCC 10231 reference strain, after their exposure to sublethal concentrations of tea tree oil (TTO) or its main bioactive component terpinen-4-ol. For all tested fluconazole-resistant C. albicans strains TTO and terpinen-4-ol minimal inhibitory concentrations (MICs) were low, ranging from 0.06% to 0.5%. The 24-hour exposure of fluconazole-resistant C. albicans strains to fluconazole with sublethal dose of TTO enhanced fluconazole activity against these strains. Overall, 62.5% of isolates were classified as susceptible, 25.0% exhibited intermediate susceptibility, and 12.5% were resistant. For all of the tested clinical strains the fluconazole MIC decreased from an average of 244.0 μg/mL to an average of 38.46 μg/mL, and the fluconazole minimal fungicidal concentrations (MFC) decreased from an average of 254.67 μg/mL to an average of 66.62 μg/mL. Terpinen-4-ol was found to be more active than TTO, and strongly enhanced fluconazole activity against fluconazole-resistant C. albicans strains. The results of this study demonstrate that combining natural substances such as TTO and conventional drug such as fluconazole, may help treat difficult yeast infections. PMID:25722982
Ultrastructure of integument wax and wax-producing structures in the melaleuca psyllid Boreioglycaspis melaleucae (Hemiptera: Psyllidae)
Technology Transfer Automated Retrieval System (TEKTRAN)
The melaleuca psyllid has been introduced to Florida as a biological control agent against Melaleuca quinquenervia, an invasive evergreen tree that has invaded large areas of Florida wetland since its introduction earlier from Australia as an ornamental plant. Colonies of the psyllid on young shoots...
Integrated management of the invasive tree Melaleuca quinquenervia in southern Florida: Special emphasis on the natural enemy impact
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian tree Melaleuca quinquenervia (melaleuca) has rapidly invaded the south Florida landscapes at the expense of native plant communities. Hence, an integrated melaleuca management program involving mechanical, chemical, cultural, and biological control methods was developed and is being u...
Risk assessment: progress of quarantine biocontrol research on Chinese Tallow, Melaleuca, and Downy Rose Myrtle
Technology Transfer Automated Retrieval System (TEKTRAN)
Risk assessments of two biocontrol candidates for Chinese tallow, Triadica sebifera (Euphoriales: Euphorbiaceae), and one for Melaleuca, Melaleuca quinquenervia (Myrtales: Myrtaceae), were conducted during 2009 and continuing into 2010 by USDA scientists located at the Florida Department of Agricul...
Decline in exotic tree density facilitates increased plant diversity: the experience from Melaleuca quinquenervia invaded wetlands
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian tree Melaleuca quinquenervia (melaleuca) formed dense monocultural forests several decades after invading Florida and the Caribbean islands. These dominant forests have displaced native vegetation in sensitive wetland systems. We hypothesized that native plant diversity would increa...
Melaleuca quinquenervia plants differ in susceptibility towards fungus Puccinia psidii infection and disease development.
Technology Transfer Automated Retrieval System (TEKTRAN)
Puccinia psidii (rust fungus) attacks immature healthy foliage of Melaleuca quinquenervia (melaleuca), an invasive plant in southern Florida, U.S.A. Melaleuca plants grown under same growing conditions manifest either susceptible or resistant reactions towards this fungus. We hypothesize that the va...
The role of melaleuca control in Everglades restoration: accomplishments and future plans
Technology Transfer Automated Retrieval System (TEKTRAN)
The invasive tree Melaleuca quinquenervia (Cav.) S.T. Blake, melaleuca, was first introduced to Florida in 1886 for ornamental use. It was later planted for bank stabilization and as a forestry crop. Melaleuca now invades a variety of habitats, changing the hydroperiod and fire regime, reducing plan...
Herbivory by introduced insects reduces growth and survival of Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia (Cav.) Blake (Myrtaceae) (melaleuca) is a native to eastern Australia and has been introduced to various locations around the world. One hundred years after its introduction into Florida, melaleuca grows spontaneously and displaces native plants as well as animals in the wetl...
Melaleuca quinquenervia dominated forests in Florida: analyses of natural-enemy impacts on stand dynamics
Technology Transfer Automated Retrieval System (TEKTRAN)
Invasion by the Australian tree, Melaleuca quinquenervia (melaleuca) resulted in near-monoculture stands in vast areas of south Florida. Introduced natural enemies are hypothesized to suppress melaleuca populations and facilitate the return of native species. To test this hypothesis, we used publish...
Dynamics of invasive plant monocultures following the establishment of natural enemies: an example from the Melaleuca quinquenervia system in Florida
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia (melaleuca), a native tree of Australian origin has become one of the most invasive plants in Florida. Biological control was implemented as a long-term solution to melaleuca control in Florida. Now several natural enemies (insects and a pathogen) of melaleuca are well estab...
Optimization of Extraction Conditions for Maximal Phenolic, Flavonoid and Antioxidant Activity from Melaleuca bracteata Leaves Using the Response Surface Methodology.
Hou, Wencheng; Zhang, Wei; Chen, Guode; Luo, Yanping
Melaleuca bracteata is a yellow-leaved tree belonging to the Melaleuca genus. Species from this genus are known to be good sources of natural antioxidants, for example, the "tea tree oil" derived from M. alternifolia is used in food processing to extend the shelf life of products. In order to determine whether M. bracteata contains novel natural antioxidants, the components of M. bracteata ethanol extracts were analyzed by gas chromatography-mass spectrometry. Total phenolic and flavonoid contents were extracted and the antioxidant activities of the extracts evaluated. Single-factor experiments, central composite rotatable design (CCRD) and response surface methodology (RSM) were used to optimize the extraction conditions for total phenolic content (TPC) and total flavonoid content (TFC). Ferric reducing power (FRP) and 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging capacity were used as the evaluation indices of antioxidant activity. The results showed that the main components of M. bracteata ethanol extracts are methyl eugenol (86.86%) and trans-cinnamic acid methyl ester (6.41%). The single-factor experiments revealed that the ethanol concentration is the key factor determining the TPC, TFC, FRP and DPPH·scavenging capacity. RSM results indicated that the optimal condition of all four evaluation indices was achieved by extracting for 3.65 days at 53.26°C in 34.81% ethanol. Under these conditions, the TPC, TFC, FRP and DPPH·scavenging capacity reached values of 88.6 ± 1.3 mg GAE/g DW, 19.4 ± 0.2 mg RE/g DW, 2.37 ± 0.01 mM Fe2+/g DW and 86.0 ± 0.3%, respectively, which were higher than those of the positive control, methyl eugenol (FRP 0.97 ± 0.02 mM, DPPH·scavenging capacity 58.6 ± 0.7%) at comparable concentrations. Therefore, the extracts of M. bracteata leaves have higher antioxidant activity, which did not only attributed to the methyl eugenol. Further research could lead to the development of a potent new natural antioxidant. PMID
Liver X Receptor and Peroxisome Proliferator-Activated Receptor Agonist from Cornus alternifolia
He, Yang-Qing; Ma, Guo-Yi; Peng, Jiang-nan; Ma, Zhan-Ying; Hamann, Mark T.
Background Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptors superfamily and are transcription factors activated by specific ligands. Liver X receptors (LXR) belong to the nuclear hormone receptors and have been shown to play an important role in cholesterol homeostasis. From the previous screening of several medicinal plants for potential partial PPARγ agonists, the extracts of Cornus alternifolia were found to exhibit promising bioactivity. In this paper, we report the isolation and structural elucidation of four new compounds and their potential as ligands for PPAR. Methods The new compounds were extracted from the leaves of Cornus alternifolia and fractionated by high-performance liquid chromatography. Their structures were elucidated on the basis of spectroscopic evidence and analysis of their hydrolysis products. Results Three new iridoid glycosides including an iridolactone, alternosides A-C (1–3), a new megastigmane glycoside, cornalternoside (4) and 10 known compounds, were obtained from the leaves of Cornus alternifolia. Kaempferol-3-O-β-glucopyranoside (5) exhibited potent agonistic activities for PPARα, PPARγ and LXR with EC50 values of 0.62, 3.0 and 1.8 μ M, respectively. Conclusions We isolated four new and ten known compounds from Cornus alternifolia, and one known compound showed agonistic activities for PPARα, PPARγ and LXR. General significance Compound 1 is the first example of a naturally occurring iridoid glycoside containing a β-glucopyranoside moiety at C-6. PMID:22353334
Invasion of Caribbean Island Wetlands by Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian native Melaleuca quinquenervia has been introduced internationally for ornamental, timber, and soil stabilization purposes. M. quinquenervia was also planted in Florida, USA in hopes of drying up "useless" swamps so as to facilitate development. M. quinquenervia quickly naturalized in...
Influence of Temperature, Humidity, and Plant Terpenoid Profiles on Life History Characteristics of Boreioglycaspis melaleucae (Hemiptera: Psyllidae), a Biological Control Agent of the Invasive Tree Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
Although the introduced weed biological control agent Boreioglycaspis melaleucae Moore is widely established among stands of its host Melaleuca quinquenervia (Cav.) Blake (Myrtaceae) in south Florida, it's population densities decline markedly during summer months. We investigated the hypothesis tha...
Effect of local application of tea tree (Melaleuca alternifolia) oil gel on long pentraxin level used as an adjunctive treatment of chronic periodontitis: A randomized controlled clinical study
Elgendy, Enas Ahmed; Ali, Shereen Abdel-Moula; Zineldeen, Doaa Hussien
Background: Conventional non-surgical periodontal therapy has been proven to be an effective treatment for patients with chronic periodontitis. Tea tree oil (TTO) can be used as adjunct to conventional periodontal therapy in patient with chronic periodontitis. The aim of this study was to evaluate the effectiveness of adjunctive treatment of TTO on the clinical parameters and the level of pentraxin-3 (PTX3) in chronic periodontitis. Materials and Methods: A total of 40 patients with moderate to severe chronic periodontitis were divided into two groups, Group I received scaling and root planing (SRP) only, Group II received SRP and TTO gel. Clinical parameters were recorded and gingival crevicular fluid (GCF) samples were collected from each subject for measuring PTX3 levels at baseline, 1, 3 and 6 months after treatment. Results: In all evaluation periods, there was statistically significant reduction in each of the studied clinical parameters and PTX3 level in Group II as compared with Group I. Conclusions: The local delivery of TTO gel in case of chronic periodontitis may have some beneficial effects to augment the results of the conventional periodontal therapy. Moreover, it places a focus on the value of monitoring GCF levels of PTX3 as a marker of periodontal tissue healing. PMID:24174722
Melaleuca quinquenervia litter accumulation, mass loss, and impact on the establishment of forest-floor vegetation in southern Florida
Technology Transfer Automated Retrieval System (TEKTRAN)
The invasive tree Melaleuca quinquenervia (melaleuca) occurs in various habitats of southern Florida where it degrades ecologically sensitive areas. The exotic tree displaces other plant species, such as Cladium jamaicense (sawgrass), from many areas, forms monoculture forests with closed canopies, ...
Temporal and structural effects of stands on litter production in Melaleuca quinquenervia dominated wetlands of South Florida
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia (melaleuca) dominates large areas of the Florida Everglades in the southeastern USA where it has transformed sedge-dominated marshes into melaleuca forests. Despite its prevalence, very little is known about the ecology and stand dynamics of this invasive tree. We delineated...
Shoot demographics for melaleuca and impacts of simulated herbivory on vegetative development
Technology Transfer Automated Retrieval System (TEKTRAN)
We monitored branches of the invasive tree Melaleuca quinquenervia (Cav.) Blake (melaleuca) at two sites in southern Florida between January 2002 and May 2003 to elucidate patterns in vegetative shoot maturation. Six shoot stages characterize development from dormancy to fully expanded and lignified...
Active rehabilitation possibilities for invasive tree occupied sites: Examples from Melaleuca quinquenervia systems in Florida
Technology Transfer Automated Retrieval System (TEKTRAN)
Accumulated litter mass suppresses seedling emergence on forest floor. This phenomenon was observed in stands of the invasive tree melaleuca tree stands in southern Florida, USA. Removal of melaleuca litter mass has been reported to enhance seedling emergence; however, the dynamics of emerged seedl...
From Invasive to Fixed-in-Place: the Transformation of Melaleuca quinquenervia in Florida
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia (melaleuca) once spread unimpeded across the south Florida landscape, infesting 0.61 million ha at its height. The complete lack of top down regulation of its growth and reproduction resulted in its rapid spread into pine flatwoods, cypress domes, sawgrass prairies, and hard...
Production, accumulation, and decomposition of Melaleuca quinquenervia litter biomass in time and space
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia (melaleuca) is highly invasive in various habitats of southern Florida where it has invaded over 200,000 hectares. Some areas have become closed-canopy monocultures with thick layers of leaf litter covering the forest floor. We hypothesized that the dramatic accumulation of...
Differential response by Melaleuca quinquenervia trees to attack by the rust fungus Puccinia psidii in Florida
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia (melaleuca, paperbark tree) is an exotic invasive tree in Florida, Hawaii, and some Caribbean islands. Puccinia psidii (guava rust-fungus) is a Neotropical rust fungus, reported to attack many species in the Myrtaceae and one genus in the Heteropyxidaceae, both members of the...
Ultrastructure of Wax-Producing Structures on the Integument of the Melaleuca Psyllid Boreioglycaspis melaleucae (Hemiptera: Psyllidae), with Honeydew Excretion Behavior in Males and Females.
Ammar, El-Desouky; Hentz, Matthew; Hall, David G; Shatters, Robert G
The melaleuca psyllid, Boreioglycaspis melaleucae (Hemiptera: Psyllidae), was introduced to Florida as a biological control agent against Melaleuca quinquenervia, an invasive evergreen tree that has invaded large areas of Florida Everglades. Colonies of B. melaleucae nymphs are normally covered by white waxy secretions, and nymphs of various instars produce long bundles of white waxy filaments extending laterally and posteriorly from their abdomen. Scanning electron microscopy of 'naturally waxed' and 'dewaxed' nymphs (cleaned from wax) revealed two types of wax pore plates located dorsally and laterally on the integument of posterior abdominal segments starting with the 4th segment. Type-1 wax pore plates, with raised rim, peripheral groove, slits and pits, produce long ribbons and filaments of waxy secretions that are wound together forming long wax bundles, whereas type-2 wax pore plates, with slits only, produce shorter wax curls. Additionally, in both nymphs and adult females, the circumanal ring contained ornate rows of wax pores that produce wax filaments covering their honeydew excretions. Video recordings with stereomicroscopy showed that adult females produce whitish honeydew balls, powerfully propelled away from their body, probably to get these sticky excretions away from their eggs and newly hatched nymphs. Adult males, however, produce clear droplets of honeydew immediately behind them, simply by bending the posterior end of the abdomen downward. The possible role(s) of waxy secretions by nymphs and adults of B. melaleucae in reducing contamination of their colonies with honeydew, among other possibilities, are discussed. PMID:25793934
Ultrastructure of Wax-Producing Structures on the Integument of the Melaleuca Psyllid Boreioglycaspis melaleucae (Hemiptera: Psyllidae), with Honeydew Excretion Behavior in Males and Females
Ammar, El-Desouky; Hentz, Matthew; Hall, David G.; Shatters, Robert G.
The melaleuca psyllid, Boreioglycaspis melaleucae (Hemiptera: Psyllidae), was introduced to Florida as a biological control agent against Melaleuca quinquenervia, an invasive evergreen tree that has invaded large areas of Florida Everglades. Colonies of B. melaleucae nymphs are normally covered by white waxy secretions, and nymphs of various instars produce long bundles of white waxy filaments extending laterally and posteriorly from their abdomen. Scanning electron microscopy of 'naturally waxed' and 'dewaxed' nymphs (cleaned from wax) revealed two types of wax pore plates located dorsally and laterally on the integument of posterior abdominal segments starting with the 4th segment. Type-1 wax pore plates, with raised rim, peripheral groove, slits and pits, produce long ribbons and filaments of waxy secretions that are wound together forming long wax bundles, whereas type-2 wax pore plates, with slits only, produce shorter wax curls. Additionally, in both nymphs and adult females, the circumanal ring contained ornate rows of wax pores that produce wax filaments covering their honeydew excretions. Video recordings with stereomicroscopy showed that adult females produce whitish honeydew balls, powerfully propelled away from their body, probably to get these sticky excretions away from their eggs and newly hatched nymphs. Adult males, however, produce clear droplets of honeydew immediately behind them, simply by bending the posterior end of the abdomen downward. The possible role(s) of waxy secretions by nymphs and adults of B. melaleucae in reducing contamination of their colonies with honeydew, among other possibilities, are discussed. PMID:25793934
Post-biological control invasion trajectory for Melaleuca quinquenervia in a seasonally inundated wetland
Technology Transfer Automated Retrieval System (TEKTRAN)
Although the exotic invasive tree Melaleuca quinquenervia has invaded and dominated South Florida wetlands since its introduction in 1886, its formerly unfettered seed production is now constrained by intentionally introduced herbivores, especially Oxyops vitiosa Pascoe (Coleoptera: Curculionidae). ...
Verbesina alternifolia Tolerance to the Holoparasite Cuscuta gronovii and the Impact of Drought
Evans, Bethany; Borowicz, Victoria
Holoparasites are nonphotosynthetic plants that acquire all resources from hosts. The holoparasite Cuscuta gronovii is native to much of the US with a broad host range including Verbesina alternifolia, an understory perennial. Both species grow in moderate to moist soils and occur in habitats that may experience prolonged or episodic drought. We applied the Wise-Abrahamson Limiting Resource Model (LRM) developed for plant-herbivore relations to examine the effects of pattern of drought stress on tolerance of V. alternifolia to parasitism by C. gronovii. Individual plants were assigned one of six treatments that were combinations of parasite (none or addition of parasite) and drought stress (well-watered, continuously-stressed, or pulse-stressed). After pulse-stressed plants had experienced two wet-dry cycles all plants were harvested. Parasitism strongly reduced both shoot and root mass and well-watered hosts exhibited the greatest decline, indicating reduced tolerance to parasitism when water was readily available. This is consistent with the LRM if parasitism limits photosynthates available to the host. However, parasitism increased allocation to shoot and this effect did not differ between well-watered and drought-stressed plants, indicating equal tolerance. This outcome is in accord with an alternative prediction of the LRM if hosts are not carbon limited. Total pot productivity was reduced by parasitism and drought stress, and this effect was greater for pulse-stressed than for continuously-stressed hosts. We discuss the applicability of the LRM for understanding the effects of drought on tolerance to parasitism. PMID:27137396
Technology Transfer Automated Retrieval System (TEKTRAN)
Plant pathogen-insect integration is becoming popular in pest plant control programs. Herein, we tested the impacts of pathogen-herbivorous insect integration in the biological control of a pest tree, Melaleuca quinquenervia (melaleuca). Melaleuca trees were cut at 25-cm above ground, allowed to cop...
Initial impacts and field validation of host range for Boreioglycaspis melaleucae Moore (Hemiptera: Psyllidae),a biological control agent of the invasive tree Melaleuca quinquenervia (Cav.) Blake (Myrtales: Myrtaceae: Leptosp
Technology Transfer Automated Retrieval System (TEKTRAN)
Invasion of south Florida wetlands by the Australian paperbark tree ("melaleuca"), Melaleuca quinquenervia (Cav.) S.T. Blake (melaleuca) has caused adverse economic and environmental impacts. The tree's biological attributes along with favorable ambient biophysical conditions combine to complicate ...
Geographic distribution and regional impacts of Oxyops vitiosa (Coleoptera: Curculionidae) and Boreioglycaspis melaleucae (Hemiptera: Psyllidae), biological control agents of the invasive tree Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
The invasive tree Melaleuca quinquenervia (Cav.) Blake is widely distributed throughout peninsular Florida, USA and poses a significant threat to species diversity in the wetland systems of the Everglades. Mitigation of this threat includes the areawide release campaign of the biological control age...
Aboveground biomass of an invasive tree Melaleuca (Melaleuca quinquenervia) before and after herbivory by adventive and introduced natural enemies: a temporal case-study in Florida
Technology Transfer Automated Retrieval System (TEKTRAN)
Invasive plants may respond to injury from natural enemies by altering the quantity and distribution of biomass among woody materials, foliage, fruits, and seeds. Melaleuca, an Australian tree that has naturalized in south Florida, USA, has been reunited with two natural enemies: a weevil introduce...
In vitro antibacterial activity of Tabernaemontana alternifolia (Roxb) stem bark aqueous extracts against clinical isolates of methicillin resistant Staphylococcus aureus
Background The rise of antibiotic resistance among methicillin resistant Staphylococcus aureus (MRSA), have caused concerns for the treatment of MRSA infections. Hence, search for an alternative therapy for these infections is inevitable. Folk Indian medicine refers to the use of leaf and stem bark powder of Tabernaemontana alternifolia (Roxb) in treatment of skin infections, but no scientific report establishes its antibacterial activity. Methods Direct aqueous extracts and sequential aqueous extracts of the stem bark of T. alternifolia (using petroleum ether and ethyl acetate as other solvents) were prepared by soxhlet extraction. The antibiotic sensitivity profiles of the clinical isolates were determined against 18 antibiotics using disc diffusion method. The isolates were identified by 16S rRNA gene sequencing. The methicillin resistance among S. aureus (MRSA) was confirmed by PCR amplification of mecA gene. The disc diffusion method was used to determine the antibacterial activity of the extracts. The micro-dilution method was used to determine the minimum inhibitory concentration (MIC) of the extract against the test organism. To further evaluate the therapeutic potential of the extract, cell cytotoxicity was checked on Vero cells by MTT assay. Chemical profiling of the extract was done by HPTLC method. Results The aqueous extracts of T. alternifolia stem bark exhibited antibacterial activity against Gram-positive microorganisms, particularly against clinical isolates of MRSA and vancomycin resistant S. aureus (VRSA). The minimum inhibitory concentration (MIC) of extract against the isolates ranged from 600–800 μg/ml. The extract did not exhibit cytotoxic activity against Vero cells even at the concentration of 4 mg/ml. The chemical profiling revealed presence of alkaloids, flavonoids, coumarins, saponins and steroids. Petroleum ether and ethyl acetate extracts did not exhibit antibacterial activity. Conclusion Our results offer a scientific basis for
Biological control of Melaleuca quinquenervia: goal-based assessment of success
Technology Transfer Automated Retrieval System (TEKTRAN)
Success means different things to different people. Unfortunately, successes in weed biological control projects are often determined after the fact by non-participants lacking knowledge of the original goals set out by project architects. The Australian tree Melaleuca quinquenervia, which is an agg...
Interactions of biological and herbicidal management of Melaleuca quinquenervia with fire: Consequences for ecosystem services
Technology Transfer Automated Retrieval System (TEKTRAN)
An example of a successful integrated pest plant management program is the Melaleuca quinquenervia (Cav.) Blake project in the Florida Everglades. Mechanical, chemical, and biological control methods have been used in concert to eliminate large monotypic stands while containing future population ex...
Biological Control of Melaleuca quinquenervia: Goal-based Assessment of Success.
Technology Transfer Automated Retrieval System (TEKTRAN)
Success means different things to different people. Unfortunately, the success or failure of weed biological control projects is often evaluated by non-participants lacking knowledge of the original goals set by project architects. The Australian tree Melaleuca quinquenervia, which is an aggressive ...
Concordance between life history traits, invasion history, and allozyme diversity of the Everglades invader Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
During the century following its initial introduction in 1886, the Australian tree Melaleuca quinquenervia(Myrtaceae) dispersed from a few introduction points to occupy over 200,000 ha, primarily in historic Everglades wetlands of southern Florida. Cellulose acetate gel electrophoresis (CAGE) was us...
Invasion of West Everglades Wetland by Melaleuca quinquenervia Countered by Classical Biological Control
Technology Transfer Automated Retrieval System (TEKTRAN)
The population dynamics of Melaleuca quinquenervia were monitored over a 5-y period in a cypress-pine wetland while subjected to two levels of herbivory. The trees had been recruited during 1998-1999 after a destructive crown fire. Half of 26 experimental plots were sprayed every 4-6 weeks with an...
T.A.M.E. Melaleuca: a regional approach for suppressing one of Florida's worst weeds
Technology Transfer Automated Retrieval System (TEKTRAN)
The adventive Australian tree Melaleuca quinquenervia (Cav.) S.T. Blake is an invasive pest plant in the greater Everglades region of Florida. Public agencies and organizations responsible for natural areas management have developed effective chemical and mechanical strategies for treating infestati...
he land manager's handbook on integrated pest management of Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
The adventive Australian tree Melaleuca quinquenervia (Cav.) S.T. Blake is an invasive pest plant in the greater Everglades region of Florida. Public agencies and organizations responsible for natural areas management have developed effective chemical and mechanical strategies for treating infestati...
Nonselective oviposition by a fastidious insect: the laboratory host range of the melaleuca gall midge Lophodiplosis trifida (Diptera: Cecidomyiidae)
Technology Transfer Automated Retrieval System (TEKTRAN)
Invasion by the Australian paperbark, Melaleuca quinquenervia, has degraded large expanses of south Florida wetlands. Restoration of these wetlands requires the removal of expansive monocultures of this large tree while simultaneously curtailing its spread. Management strategies developed by feder...
Chemical composition and biological activities of the essential oils from three Melaleuca species grown in Tunisia.
Amri, Ismail; Mancini, Emilia; De Martino, Laura; Marandino, Aurelio; Lamia, Hamrouni; Mohsen, Hanana; Bassem, Jamoussi; Scognamiglio, Mariarosa; Reverchon, Ernesto; De Feo, Vincenzo
The chemical composition of the essential oils of Melaleuca armillaris Sm., Melaleuca styphelioides Sm. and Melaleuca acuminata F. Muell., collected in Tunisia, was studied by means of GC and GC-MS analysis. In all, 46 compounds were identified, 38 for M. armillaris, 20 for M. acuminata and eight for M. styphelioides, respectively. The presence of a sesquiterpenic fraction (52.2%) characterized the oil from M. armillaris; M. sthypheliodes oil was rich in methyl eugenol, a phenolic compound (91.1%), while M. acuminata oil is mainly constituted by oxygenated monoterpenoids (95.6%). The essential oils were evaluated for their in vitro potentially phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Lepidium sativum L., Sinapis arvensis L., Triticum durum L. and Phalaris canariensis L. seeds. The radicle elongation of five seeds was inhibited at the highest doses tested, while germination of all seeds was not affected. Moreover, the essential oils showed low antimicrobial activity against eight selected microorganisms. PMID:23443119
Intraspecific variation of Melaleuca quinquenervia leaf oils in its naturalized range in FLorida, the Caribbean, and Hawaii
Technology Transfer Automated Retrieval System (TEKTRAN)
The invasive species Melaleuca quinquenervia is a weed that threatens the biodiversity of the Florida Everglades and adjacent areas. Biological control efforts have resulted in the release of three Australian insect species. Not all populations of the plant however, are equally nutritious to the bi...
Consequences of Melaleuca quinquenervia invasion of the Florida Everglades: "Notes from the underground" with specific reference to nematodes
Technology Transfer Automated Retrieval System (TEKTRAN)
We investigated the composition and diversity of nematode communities from soils dominated by the invasive tree Melaleuca quinquenervia as compared with adjacent soils supporting native non-invaded plant communities at 6 sites across the Florida Everglades over three years. Despite the significant ...
T.A.M.E. Melaleuca: a regional approach for suppressing one of Florida's worst weeds
Technology Transfer Automated Retrieval System (TEKTRAN)
The adventive Australian tree Melaleuca quinquenervia (Cav.) S.T. Blake is an invasive pest plant in the greater Everglades region of Florida. Public agencies and organizations responsible for natural areas management have developed effective chemical and mechanical strategies for treating infestati...
No evolution of increased competitive ability or decreased allocation to defense in Melaleuca quinquenervia since release from natural enemies
Technology Transfer Automated Retrieval System (TEKTRAN)
If invasive plants are released from natural enemies in their introduced range, they may evolve decreased allocation to defense and increased growth, as predicted by the evolution of increased competitive ability (EICA) hypothesis. A field experiment using the invasive tree Melaleuca quinquenervia ...
Quantum chemical and experimental study of 1,2,4-trihydroxy-para-menthane
NASA Astrophysics Data System (ADS)
Rottmannová, Lenka; Lukeš, Vladimír; Ilčin, Michal; Fodran, Peter; Herich, Peter; Kožíšek, Jozef; Liptaj, Tibor; Klein, Erik
The conformational analysis of the para-menthane (PM) and 1,2,4-trihydroxy-para-menthane (TPM) is performed using the quantum chemical density functional theory (DFT) and ab initio Møller-Plesset perturbation theory up to the second order (MP2). In TPM, three hydroxyl groups generate eight stereoisomers comparing to the four para-menthane stereoisomers. From the thermodynamics point of view, the most preferred conformations show the chair-shaped configuration of the cyclohexane ring. The obtained energy barriers for the isopropyl group rotation in the chair-shaped stereoisomers are between 35 and 45 kJ mol-1. The crystal structure as well as the solvated TPM stereoisomer isolated from the Tea tree oil, Melaleuca alternifolia (Maiden & Betche) Cheel, were investigated experimentally. Isolated stereoisomer corresponds to the most energetically preferred conformation and the calculated structural data agree very well with the results from the X-ray and nuclear magnetic resonance measurements. Finally, the influence of the conformation and the presence of the intramolecular hydrogen bonds on the homolytic Osbnd H bond dissociation enthalpies and proton affinities were also discussed with respect to the simple alcohols (methanol, iso-propanol, iso-pentanol, tert-butanol, cyclohexanol) and phenol.
Antifilarial and Antibiotic Activities of Methanolic Extracts of Melaleuca cajuputi Flowers
Al-Abd, Nazeh M.; Nor, Zurainee Mohamed; Mansor, Marzida; Hasan, MS; Kassim, Mustafa
We evaluated the activity of methanolic extracts of Melaleuca cajuputi flowers against the filarial worm Brugia pahangi and its bacterial endosymbiont Wolbachia. Anti-Wolbachia activity was measured in worms and in Aedes albopictus Aa23 cells by PCR, electron microscopy, and other biological assays. In particular, microfilarial release, worm motility, and viability were determined. M. cajuputi flower extracts were found to significantly reduce Wolbachia endosymbionts in Aa23 cells, Wolbachia surface protein, and microfilarial release, as well as the viability and motility of adult worms. Anti-Wolbachia activity was further confirmed by observation of degraded and phagocytized Wolbachia in worms treated with the flower extracts. The data provided in vitro and in vivo evidence that M. cajuputi flower extracts inhibit Wolbachia, an activity that may be exploited as an alternative strategy to treat human lymphatic filariasis. PMID:27417081
Impact of pretreatments on morphology and enzymatic saccharification of shedding bark of Melaleuca leucadendron.
Ahmed, Ibrahim Nasser; Santoso, Shella Permatasari; Tran-Nguyen, Phuong Lan; Huynh, Lien Huong; Ismadji, Suryadi; Ju, Yi-Hsu
The effects of subcritical water (SCW) and dilute acid pretreatments on the shedding bark of Melaleuca leucadendron (paper bark tree, PBT) biomass morphology, crystallinity index (CrI) and enzymatic saccharification were studied. The morphology of PBT bark was characterized by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. SCW pretreatment mainly extracted amorphous parts of the biomass hence its CrI increased, partial decrystallization of cellulose and exposing of intact nanofibers of cellulose were observed for SCW pretreatment at 180°C. On the other hand, dilute acid pretreatment at 160°C exhibited a large decrease in CrI, an increase in surface area, a decrease in lignin content and decrystallization of cellulose as well as the peel-off and degradation of some nanofiber bundles. Dilute acid and SCW pretreatments of PBT biomass resulted in about 4.5 fold enhancement in glucose release relative to the untreated one. PMID:23697662
Activated carbon derived from melaleuca barks for outstanding high-rate supercapacitors
NASA Astrophysics Data System (ADS)
Luo, Qiu-Ping; Huang, Liang; Gao, Xiang; Cheng, Yongliang; Yao, Bin; Hu, Zhimi; Wan, Jun; Xiao, Xu; Zhou, Jun
Activated carbon (AC) was prepared via carbonizing melaleuca bark in an argon atmosphere at 600 °C followed with KOH activation for high-rate supercapacitors. This AC electrode has a high capacitance of 233 F g-1 at a scan rate of 2 mV s-1 and an excellent rate capability of ˜80% when increasing the sweep rate from 2 to 500 mV s-1. The symmetric supercapacitor assembled by the above electrode can deliver a high energy density of 4.2 Wh kg-1 with a power density of 1500 W kg-1 when operated in the voltage range of 0-1 V in 1 M H2SO4 aqueous electrolyte while maintaining great cycling stability (less than 5% capacitance loss after 10 000 cycles at sweep rate of 100 mV s-1). All the outstanding electrochemical performances make this AC electrode a promising candidate for potential energy storage application.
Antifilarial and Antibiotic Activities of Methanolic Extracts of Melaleuca cajuputi Flowers.
Al-Abd, Nazeh M; Nor, Zurainee Mohamed; Mansor, Marzida; Hasan, M S; Kassim, Mustafa
We evaluated the activity of methanolic extracts of Melaleuca cajuputi flowers against the filarial worm Brugia pahangi and its bacterial endosymbiont Wolbachia. Anti-Wolbachia activity was measured in worms and in Aedes albopictus Aa23 cells by PCR, electron microscopy, and other biological assays. In particular, microfilarial release, worm motility, and viability were determined. M. cajuputi flower extracts were found to significantly reduce Wolbachia endosymbionts in Aa23 cells, Wolbachia surface protein, and microfilarial release, as well as the viability and motility of adult worms. Anti-Wolbachia activity was further confirmed by observation of degraded and phagocytized Wolbachia in worms treated with the flower extracts. The data provided in vitro and in vivo evidence that M. cajuputi flower extracts inhibit Wolbachia, an activity that may be exploited as an alternative strategy to treat human lymphatic filariasis. PMID:27417081
The Potent Inhibitors of Protein Tyrosine Phosphatase 1B from the Fruits of Melaleuca leucadendron
Saifudin, Azis; Lallo, Subehan Ab; Tezuka, Yasuhiro
Background: Melaleuca leucadendron (Myrtaceae) is a kind of fruit used as Indonesian medicinal component and recorded in Jamu (tonic made of medical herbs) prescription records for the diabetes treatment. Its methanol extract exhibited a strong inhibitory activity with the half maximal inhibitory concentration (IC50) value of 2.05 μg/mL, while it is the same value with positive control RK-682. Objective: To isolate the chemical constituents of M. leucadendron and to evaluate their activity against protein tyrosine phosphatase 1B (PTP1B). Further, determine their toxicity potential against T-cell protein tyrosine phosphatase (TCPTP). Materials and Methods: Methanol extract was fractionated using silica column chromatography, and the obtained fraction was purified using Sephadex 20-LH. The structure of isolated compounds was identified based on 1H and 13Nuclear Magnetic Resonance Spectrometry. Furthermore, the compounds were examined against PTP1B and TCPTP. Results: Methanol extract of M. leucadendron (Myrtaceae) afforded two triterpenes: Betulinic acid and ursolic acid in high quantities. Both compounds exhibited a strong inhibitory activity against PTP1B inhibition with IC50 value of 1.5 and 2.3 μg/mL, respectively (positive control RK-682, IC50 = 2.05 μg/mL). Their activity toward TCPTP, on the other hand, were at 2.4 and 3.1 μg/mL, respectively. Based on this purification work, betulinic acid and ursolic acid presented 7.6% and 2.4%, respectively, as markedly M. leucadendron most potential for betulinic acid source among Indonesian plants. The result should have demonstrated that the antidiabetes of M. dendron could be through the inhibition of PTP1B. SUMMARY Melaleuca leucadendron is a good source for ursolic acid.Confirming traditional use for type II diabetes via PTP1B inhibition. PMID:27114690
Extraction and refining of essential oil from Australian tea tree, Melaleuca alterfornia, and the antimicrobial activity in cosmetic products
NASA Astrophysics Data System (ADS)
Huynh, Q.; Phan, T. D.; Thieu, V. Q. Q.; Tran, S. T.; Do, S. H.
Tea tree oil (TTO) comes from the leaves of Melaleuca alternifornia that belongs to the myrtle family (Myrtaceae). It is one of the most powerful immune system stimulants and sorts out most viral, bacterial and fungal infections in a snap, while it is great to heal wounds and acnes. In Vietnam, Melaleuca trees can grow on acid land that stretches in a large portion of lands in the Mekong Delta region. So, there are some Melaleuca plantations developed under the Vietnamese government plans of increasing plantation forests now. However, TTO contains various amounts of 1,8-cineole that causes skin irritant. So TTO purification is very necessary. In this study, the purification of TTO that meet International Standard ISO 4730 was carried out via two steps. The first step is steam distillation to obtain crude TTO (terpinen-4-ol 35% v/v) and the average productivity is among 2.37% (v/wet-wt) or 1.23% (v/dry-wt). In the second step, the cleaned TTO is collected by vacuum distillation column and extraction yield of the whole process is about 0.3% (w/w). Besides, high concentration essential oil was applied in the cosmetic products to increase its commercial value.
Activated carbon derived from melaleuca barks for outstanding high-rate supercapacitors.
Luo, Qiu-Ping; Huang, Liang; Gao, Xiang; Cheng, Yongliang; Yao, Bin; Hu, Zhimi; Wan, Jun; Xiao, Xu; Zhou, Jun
Activated carbon (AC) was prepared via carbonizing melaleuca bark in an argon atmosphere at 600 °C followed with KOH activation for high-rate supercapacitors. This AC electrode has a high capacitance of 233 F g(-1) at a scan rate of 2 mV s(-1) and an excellent rate capability of ∼80% when increasing the sweep rate from 2 to 500 mV s(-1). The symmetric supercapacitor assembled by the above electrode can deliver a high energy density of 4.2 Wh kg(-1) with a power density of 1500 W kg(-1) when operated in the voltage range of 0-1 V in 1 M H2SO4 aqueous electrolyte while maintaining great cycling stability (less than 5% capacitance loss after 10 000 cycles at sweep rate of 100 mV s(-1)). All the outstanding electrochemical performances make this AC electrode a promising candidate for potential energy storage application. PMID:26152815
Fergusobia/Fergusonina-induced Shoot Bud Gall Development on Melaleuca quinquenervia
Giblin-Davis, R. M.; Makinson, J.; Center, B. J.; Davies, K. A.; Purcell, M.; Taylor, G. S.; Scheffer, S. J.; Goolsby, J.; Center, T. D.
Fergusobia nematodes and Fergusonina flies are mutualists that cause a variety of gall types on myrtaceous plant buds and young leaves. The biology of an isolate of the gall complex was studied in its native range in Australia for possible use in southern Florida as a biological control agent against the invasive broad-leaved paperbark tree, Melaleuca quinquenervia. Timed studies with caged Fergusonina flies on young branches of M. quinquenervia revealed that females are synovigenic with lifetime fecundities of 183 ± 42 (standard error; SE) eggs and longevities of 17 ± 2 days. None of the male flies but all dissected female flies contained parasitic female nematodes (range = 3-15), nematode eggs (12-112), and nematode juveniles (78-1,750). Female flies deposited eggs (34 ± 6; 8-77 per bud) and nematode juveniles (114 ± 15; 44-207 per bud) into bud apices within 15 days. Histological sections of shoot buds suggested that nematodes induce the formation of hypertrophied, uninucleate plant cells prior to fly larval eclosion. Enlarged size, granular cytoplasm, and enlarged nucleus and nucleolus characterized these cells, which appeared similar to those of other species galled by nematodes in the Anguinidae. Observations of ovipositional behavior revealed that female Fergusonina sp. create diagnostic oviposition scars. The presence of these scars may facilitate recognition of host use during specificity screening. PMID:19265887
Antioxidant and Anti-inflammatory Activities of Butanol Extract of Melaleuca leucadendron L.
Surh, Jeonghee; Yun, Jung-Mi
Melaleuca leucadendron L. has been used as a tranquilizing, sedating, evil-dispelling and pain-relieving agent. We examined the effects of M. leucadendron L. extracts on oxidative stress and inflammation. M. leucadendron L. was extracted with methanol (MeOH) and then fractionated with chloroform (CHCl3) and butanol (BuOH). Antioxidant activity of the MeOH extract and BuOH fraction were higher than that of both α-tocopherol and butyrated hydroxytoluene (BHT). Total phenol content in the extracts of M. leucadendron L., especially the BuOH fraction, well correlated with the antioxidant activity. The anti-inflammatory activity of BuOH extracts were investigated by lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production, and cyclooxygenase-2 (COX-2) expression in RAW 264.7 macrophages. The BuOH fraction significantly inhibited LPS-induced NO and PGE2 production. Furthermore, BuOH extract of M. leucadendron L. inhibited the expression of COX-2 and iNOS protein without an appreciable cytotoxic effect on RAW264.7 cells. The extract of M. leucadendron L. also suppressed the phosphorylation of inhibitor κBα (IκBα) and its degradation associated with nuclear factor-κB (NF-κB) activation. Furthermore, BuOH fraction inhibited LPS-induced NF-κB transcriptional activity in a dose-dependent manner. These results suggested that M. leucadendron L. could be useful as a natural anti-oxidant and anti-inflammatory resource. PMID:24471059
Physiological host range of a mutualistic pair: Fergusonina turneri and its obligate nematode Fergusobia quinquenerviae, potential biological control agents of Melaleuca quinquenervia
Technology Transfer Automated Retrieval System (TEKTRAN)
In Australia, galls develop on Melaleuca quinquenervia (Cav.) S.T. Blake (Myrtales: Myrtaceae) as a result of the mutualistic association between the fly Fergusonina turneri Taylor (Diptera: Fergusoninidae) and its obligate nematode Fergusobia quinquenerviae Davies & Giblin-Davis (Tylenchida: Sphaer...
Establishment, population increase, spread, and ecological host range of Lophodiplosis trifida (Diptera: Cecidomyiidae), a biological control agent of the invasive tree Melaleuca quinquenervia (Myrtales:Myrtaceae).
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian tree Melaleuca quinquenervia (Cav.) Blake is an invasive weed in wetland systems of Florida, USA. A biological control program targeting M. quinquenervia has culminated in the release of the gall forming midge Lophodiplosis trifida Gagné (Cecidomyiidae). Populations of the introduced ...
Interregional comparison of the size-structure of populations of Melaleuca quinquenervia in its native and exotic range, with and without biocontrol agents
Technology Transfer Automated Retrieval System (TEKTRAN)
We compare size structure and rates of recruitment and mortality in populations of Melaleuca quinquenervia in its native and exotic ranges. In the exotic range study sites were chosen to include contrasts in presence and abundance of two biological control agents. We tagged and measured (DBH) all ...
Bioethanol production from pretreated Melaleuca leucadendron shedding bark--simultaneous saccharification and fermentation at high solid loading.
Ahmed, Ibrahim Nasser; Nguyen, Phuong Lan Tran; Huynh, Lien Huong; Ismadji, Suryadi; Ju, Yi-Hsu
Bioethanol production from the shedding bark of Melaleuca leucadendron (Paper-bark Tree, PBT) was studied using subcritical water (SCW) pretreatment at various severities (So). High ethanol production was attained by implementing a factorial design on three parameters (So, solid loading and enzyme loading) in simultaneous saccharification and fermentation (SSF) mode. Ethanol concentration of 63.2 g L(-1) corresponding to ethanol yield of 80.9% were achieved from pretreated biomass (So=2.37) at 0.25 g mL(-1) solid and 16 FPU g(-1) glucan enzyme loadings. Similarly at 0.15 g mL(-1) solid loadings both high ethanol concentration (43.7 g L(-1)) and high ethanol yield (91.25%) were achieved. Regression analysis of experimental results shows that all process parameters had significant role on maximum ethanol production, glucose solubility, ethanol yield and ethanol volumetric productivity. SSF of SCW treated PBT biomass is economically feasible for production of bioethanol. PMID:23570711
Antipredator defense of biological control agent Oxyops vitiosa is mediated by plant volatiles sequestered from the host plant Melaleuca quinquenervia.
Wheeler, G S; Massey, L M; Southwell, I A
The weevil Oxyops vitiosa is an Australian species imported to Florida, USA, for the biological control of the invasive weed species Melaleuca quinquenervia. Larvae of this species feed on leaves of their host and produce a shiny orange secretion that covers the integument. When this secretion is applied at physiological concentrations to dog food bait, fire ant consumption and visitation are significantly reduced. Gas chromatographic analysis indicates that the larval secretion qualitatively and quantitatively resembles the terpenoid composition of the host foliage. When the combination of 10 major terpenoids from the O. vitiosa secretion was applied to dog food bait, fire ant consumption and visitation were reduced. When these 10 terpenoids were tested individually, the sesquiterpene viridiflorol was the most active component in decreasing fire ant consumption. Fire ant visitation was initially (15 min after initiation of the study) decreased for dog food bait treated with viridiflorol and the monoterpenes 1,8-cineole and alpha-terpineol. Fire ants continued to avoid the bait treated with viridiflorol at 18 microg/mg dog food for up to 6 hr after the initiation of the experiment. Moreover, ants avoided bait treated with 1.8 microg/mg for up to 3 hr. The concentrations of viridiflorol, 1,8-cineole, and alpha-terpineol in larval washes were about twice that of the host foliage, suggesting that the larvae sequester these plant-derived compounds for defense against generalist predators. PMID:11925069
Chemical study and antimalarial, antioxidant, and anticancer activities of Melaleuca armillaris (Sol Ex Gateau) Sm essential oil.
Chabir, Naziha; Romdhane, Mehrez; Valentin, Alexis; Moukarzel, Béatrice; Marzoug, Hajer Naceur Ben; Brahim, Nadia Ben; Mars, Mohamed; Bouajila, Jalloul
This study investigated the chemical composition (by using gas chromatography/flame ionization detection and gas chromatography/mass spectrometry, an antioxidant [1,1-diphenyl-2-picrylhydrazyl] [DPPH] radical-scavenging assay, and a 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonate [ABTS] radical cation-scavenging assay) and the antimalarial and cytotoxic activities of essential oil extracted from leaves of Melaleuca armillaris. Thirty-two components representing more than 98% of the total composition of the essential oil were identified. The main components were 1,8-cineole (85.8%), camphene (5.05%), and α-pinene (1.95%). The antioxidant activity by ABTS assay showed a mean (± standard deviation) 50% inhibitory concentration (IC(50)) value of 247.3 ± 3.9 mg/L, and the DPPH assay yielded an IC(50) value of 2183.6 ± 44.3 mg/L. The antimalarial study indicated that the essential oil had mild activity against the chloroquine-resistant Plasmodium falciparum FcB1 strain (IC(50), 27 ± 2 mg/L). The cytotoxic activity of this essential oil was tested against MCF7 human breast cancer cells and was found to be high (IC(50), 12 ± 1 mg/L). PMID:21476932
In vitro anti-microbial activity of the Cuban medicinal plants Simarouba glauca DC, Melaleuca leucadendron L and Artemisia absinthium L.
Valdés, Aymé Fernández-Calienes; Martínez, Judith Mendiola; Lizama, Ramón Scull; Vermeersch, Marieke; Cos, Paul; Maes, Louis
In the present study, an extensive in vitro antimicrobial profiling was performed for three medicinal plants grown in Cuba, namely Simarouba glauca, Melaleuca leucadendron and Artemisia absinthium. Ethanol extracts were tested for their antiprotozoal potential against Trypanosoma b. brucei, Trypanosoma cruzi, Leishmania infantum and Plasmodium falciparum. Antifungal activities were evaluated against Microsporum canis and Candida albicans whereas Escherichia coli and Staphylococcus aureus were used as test organisms for antibacterial activity. Cytotoxicity was assessed against human MRC-5 cells. Only M. leucadendron extract showed selective activity against microorganisms tested. Although S. glauca exhibited strong activity against all protozoa, it must be considered non-specific. The value of integrated evaluation of extracts with particular reference to selectivity is discussed. PMID:18949336
Carbon isotope discrimination in leaves of the broad-leaved paperbark tree, Melaleuca quinquenervia, as a tool for quantifying past tropical and subtropical rainfall.
Tibby, John; Barr, Cameron; McInerney, Francesca A; Henderson, Andrew C G; Leng, Melanie J; Greenway, Margaret; Marshall, Jonathan C; McGregor, Glenn B; Tyler, Jonathan J; McNeil, Vivienne
Quantitative reconstructions of terrestrial climate are highly sought after but rare, particularly in Australia. Carbon isotope discrimination in plant leaves (Δleaf ) is an established indicator of past hydroclimate because the fractionation of carbon isotopes during photosynthesis is strongly influenced by water stress. Leaves of the evergreen tree Melaleuca quinquenervia have been recovered from the sediments of some perched lakes on North Stradbroke and Fraser Islands, south-east Queensland, eastern Australia. Here, we examine the potential for using M. quinquenervia ∆leaf as a tracer of past rainfall by analysing carbon isotope ratios (δ(13) C) of modern leaves. We firstly assess Δleaf variation at the leaf and stand scale and find no systematic pattern within leaves or between leaves due to their position on the tree. We then examine the relationships between climate and Δleaf for a 11-year time series of leaves collected in a litter tray. M. quinquenervia retains its leaves for 1-4 years; thus, cumulative average climate data are used. There is a significant relationship between annual mean ∆leaf and mean annual rainfall of the hydrological year for 1-4 years (i.e. 365-1460 days) prior to leaf fall (r(2) = 0.64, P = 0.003, n = 11). This relationship is marginally improved by accounting for the effect of pCO2 on discrimination (r(2) = 0.67, P = 0.002, n = 11). The correlation between rainfall and Δleaf , and the natural distribution of Melaleuca quinquenervia around wetlands of eastern Australia, Papua New Guinea and New Caledonia offers significant potential to infer past rainfall on a wide range of spatial and temporal scales. PMID:27090595
Holocene precipitation in the subtropical Pacific inferred from the carbon isotope composition of Melaleuca quinquenervia (The Broad-leaved Paper Bark tree) leaves
NASA Astrophysics Data System (ADS)
Tibby, John; Barr, Cameron; Henderson, Andrew; Leng, Melanie; Marshall, Jon; McGregor, Glenn
Holocene records of the amounts of subtropical precipitation are rare, particularly in the Southern Hemisphere. Yet such information is vital for a comprehensive understanding of global climate system dynamics. We present a precipitation record inferred from the δ13C composition of Melaleuca quinquenervia leaves retrieved from the Holocene sediments of Swallow Lagoon, North Stradbroke Island, in the subtropics of Australia. The modern relationship between rainfall and δ13C was quantified using a collection of monthly leaf falls between 1992 and 2003 and climate data. We then used the calibration to reconstruct precipitation variability from 7500 to 600 cal. yr BP. Dry phases at Swallow Lagoon in the early to mid Holocene are correlated with cooling in the North Atlantic Ocean (i.e. "Bond" events). This relationship breaks down after ~3500 cal. yr BP. From 3500 cal. yr BP there is increased aridity (and variability) associated with the mid- to late Holocene establishment of modern El Niño Southern Oscillation conditions. Overall, these data show linkages between precipitation in the low latitudes of the Southern Hemisphere and Northern Hemisphere cooling events, with a shift to internal forcing of subtropical climate via the Pacific Ocean in the late Holocene.
Nematodes from galls on Myrtaceae. X. Fergusobia from galls on narrow-leaved Melaleuca spp. in Australia, with descriptions of three new species .
Davies, Kerrie A; Giblin-Davis, Robin M; Ye, Weimin; Taylor, Gary S; Makinson, Jeff; Purcell, Matthew
Three new species of Fergusobia, respectively collected from shoot bud galls on narrow-leaved Melaleuca spp. in Australia, are described. Fergusobia armillarisae n. sp. Davies is characterised by the combination of an arcuate to open C-shaped parthenogenetic female with an extensile uterus and a short, conoid tail, an arcuate infective female with a broadly rounded tail tip, and an arcuate male with an angular spicule and bursa arising at 50-80% of body length. Fergusobia decorae n. sp. Davies has an arcuate parthenogenetic female with a non-extensile uterus and a broadly conoid tail, an arcuate infective female with most curvature behind the vulva and a short tail with a broadly rounded tip, and an arcuate male with an arcuate spicule and bursa arising at 40-50% of body length. Fergusobia linariifoliae n. sp. Davies is characterised by the combination of an arcuate parthenogenetic female with an extensile uterus and a short, conoid tail with a bluntly rounded tip, a barely arcuate infective female with a broadly rounded tail tip, and an arcuate male with an angular spicule and bursa arising at 40-50% of body length. Earlier molecular analyses inferred from DNA sequencing of 28S rDNA D2/D3 domains and a portion of mitochondrial DNA cytochrome oxidase subunit I (mtCOI) are further discussed. PMID:25544141
In chemico evaluation of tea tree essential oils as skin sensitizers. Impact of the chemical composition on aging and generation of reactive species.
Technology Transfer Automated Retrieval System (TEKTRAN)
Tea tree oil (TTO) is a popular skin remedy obtained from the leaves of Melaleuca alternifolia, M. linariifolia or M dissitiflora. Due to the commercial importance ofTTO, substitution or adulteration with other tea tree species (such as cajeput, niaouli, manuka and kanuka oils) is common and may p...
Sensitation potential of tea tree essential oils. Impact of the chemical composition on aging and generation of reactive species.
Technology Transfer Automated Retrieval System (TEKTRAN)
Tea tree oil (TTO) is a popular skin remedy obtained from the leaves of Melaleuca alternifolia, M. linariifolia or M dissitiflora. Due to the commercial importance ofTTO, substitution or adulteration with other tea tree species (such as cajeput, niaouli, manuka and kanuka oils) is common and may p...
Mosquitocidal essential oils: are they safe against non-target aquatic organisms?
Conti, Barbara; Flamini, Guido; Cioni, Pier Luigi; Ceccarini, Lucia; Macchia, Mario; Benelli, Giovanni
In latest years, the importance of the Melaleuca alternifolia essential oil (EO) has been greatly empathised due to its anti-microbial and anti-inflammatory effects, as well as to its toxic properties towards many arthropods of great medical and veterinary importance. In this research, the EO extracted from aerial parts of M. alternifolia was evaluated for its toxicity against larvae of the most invasive mosquito worldwide, Aedes albopictus (Diptera: Culicidae), and towards adults of the water flea, Daphnia magna (Cladocera: Crustacea), a non-target aquatic organism that share the same ecological niche of A. albopictus. The chemical composition of M. alternifolia EO was investigated by GC-MS analysis. Tea tree EO was mainly composed by oxygenated monoterpenes, with 1,8-cineole as the major constituent. M. alternifolia EO exerted toxic activity against A. albopictus larvae, with a LC50 = 267.130 ppm. However, this EO had a remarkable acute toxicity also towards adults of the non-target arthropod D. magna, with a LC50 = 80.636 ppm. This research provide useful information for the development of newer and safer mosquito control tools, highlighting that the non-target effects against aquatic organisms that share the same ecological niche of A. albopictus larvae are crucial in the development of ecofriendly mosquito control strategies. Further research is needed to investigate the chronic and/or reproductive toxicity of M. alternifolia EO both towards target and non-target aquatic arthropods. PMID:24146210
Properties and limits of some essential oils: chemical characterisation, antimicrobial activity, interaction with antibiotics and cytotoxicity.
Scazzocchio, Francesca; Garzoli, Stefania; Conti, Cinzia; Leone, Claudia; Renaioli, Clio; Pepi, Federico; Angiolella, Letizia
Because of the emergence of multi-drug resistance bacteria and fungi, alternatives to conventional antimicrobial therapy are needed. This study aims to evaluate in vitro the antimicrobial activity of: Mirtus communis, Coriandrum sativum, Pelargonium capitatum, Cuminum cyminum, Ocimum basilicum, Citrus aurantium amara, Cymbopogon. winterianus, Cymbopogon martini, Salvia sclarea, Melaleuca alternifolia and Mentha suaveolens essential oils on bacteria and fungi, in relation to their chemical composition. The potential interaction of M. alternifolia (TTO), C. sativum (CDO) and M. suaveolens (EOMS) essential oils when used in combination with gentamicin and fluconazole has been evaluated. The results obtained showed a synergic effect on some bacteria and fungi, with FICI values ≤5. The cytotoxicity of TTO, CDO and EOMS was investigated towards HeLa cells. Only EOMS did not result cytotoxic at the active concentrations on micro-organisms. Further studies are necessary to obtain optimal ratios and dosing regimens for higher therapeutic efficacy and to decrease toxicological profiles. PMID:26395247
Catalyst-Free Plasma Enhanced Growth of Graphene from Sustainable Sources.
Jacob, Mohan V; Rawat, Rajdeep S; Ouyang, Bo; Bazaka, Kateryna; Kumar, D Sakthi; Taguchi, Dai; Iwamoto, Mitsumasa; Neupane, Ram; Varghese, Oomman K
Details of a fast and sustainable bottom-up process to grow large area high quality graphene films without the aid of any catalyst are reported in this paper. We used Melaleuca alternifolia, a volatile natural extract from tea tree plant as the precursor. The as-fabricated graphene films yielded a stable contact angle of 135°, indicating their potential application in very high hydrophobic coatings. The electronic devices formed by sandwiching pentacene between graphene and aluminum films demonstrated memristive behavior, and hence, these graphene films could find use in nonvolatile memory devices also. PMID:26263025
Antibacterial activity of essential oils from Australian native plants.
Wilkinson, Jenny M; Cavanagh, Heather M A
To date, of the Australian essential oils, only tea tree (Melaleuca alternifolia) and Eucalyptus spp. have undergone extensive investigation. In this study a range of Australian essential oils, including those from Anethole anisata, Callistris glaucophyllia, Melaleuca spp. and Thyptomine calycina, were assayed for in vitro antibacterial activity. M. alternifolia was also included for comparison purposes. Activity was determined using standard disc diffusion assays with each oil assayed at 100%, 10% and 1% against five bacteria (Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, Pseudomonas aeruginosa and Alcaligenes faecalis) and the yeast, Candida albicans. All bacteria, with the exception of Ps. aeruginosa, were susceptible to one or more of the essential oils at 100%, with only Eremophilia mitchelli inhibiting the growth of any bacteria at 1% (inhibition of Sal. typhimurium). Where multiple samples of a single oil variety were tested variability in activity profiles were noted. This suggests that different methods of preparation of essential oils, together with variability in plant chemical profiles has an impact on whether or not the essential oil is of use as an antimicrobial agent. These results show that essential oils from Australian plants may be valuable antimicrobial agents for use alone or incorporated into cosmetics, cleaning agents and pharmaceutical products. PMID:16161028
Inhibitory effect of essential oils against Trichosporon ovoides causing Piedra Hair Infection.
Saxena, Seema; Uniyal, Veena; Bhatt, R P
Piedra, is an asymptomatic fungal infection of the hair shaft, resulting in the formation of nodules of different hardness on the infected hair. The infection also known as Trichomycosis nodularis is a superficial fungal infection arising from the pathogen being restricted to the stratum corneum with little or no tissue reaction. The nodules are a concretion of hyphae and fruiting bodies of the fungus. Two varieties of Piedra may be seen, Black Piedra and White Piedra. The fungus Trichosporon ovoides is involved in the occurrence of both types of Piedras. The purpose of this study was to examine the effectiveness of selected essential oils for the control of growth of the fungus and to determine whether the antifungal effect was due to the major compounds of the oils. Two screening methods viz. Agar well diffusion assay and Minimum Inhibitory Concentration were adopted for the study. MIC and MFC were determined by tube dilution method. Essential oils from Eucalyptus, Ocimum basilicum, Mentha piperita, Cymbopogon flexuosus, Cymbopogon winterians, Trachyspermum ammi, Zingiber officinalis, Citrus limon, Cinnamomon zeylanicum, Salvia sclarea, Citrus aurantifolia, Melaleuca alternifolia, Citrus aurantium, Citrus bergamia, Pogostemon pathchouli, Cedrus atlantica, Jasminum officinale, Juniperus communis, Abelmoschus moschatus, Cyperus scariosus, Palargonium graveolens, Boswellia carterii, Rosa damascene, Veteveria zizanoides and Commiphora myrrha were evaluated. The essential oils of Cymbopogon winterians, Mentha piperita, Cinnamomum zeylanicum, Melaleuca alternifolia and Eucalyptus globulus were proved to be most effective against the fungus Trichosporon ovoides. PMID:24031963
Inhibitory effect of essential oils against Trichosporon ovoides causing Piedra Hair Infection
Saxena, Seema; Uniyal, Veena; Bhatt, R.P.
Piedra, is an asymptomatic fungal infection of the hair shaft, resulting in the formation of nodules of different hardness on the infected hair. The infection also known as Trichomycosis nodularis is a superficial fungal infection arising from the pathogen being restricted to the stratum corneum with little or no tissue reaction. The nodules are a concretion of hyphae and fruiting bodies of the fungus. Two varieties of Piedra may be seen, Black Piedra and White Piedra. The fungus Trichosporon ovoides is involved in the occurrence of both types of Piedras. The purpose of this study was to examine the effectiveness of selected essential oils for the control of growth of the fungus and to determine whether the antifungal effect was due to the major compounds of the oils. Two screening methods viz. Agar well diffusion assay and Minimum Inhibitory Concentration were adopted for the study. MIC and MFC were determined by tube dilution method. Essential oils from Eucalyptus, Ocimum basilicum, Mentha piperita, Cymbopogon flexuosus, Cymbopogon winterians, Trachyspermum ammi, Zingiber officinalis, Citrus limon, Cinnamomon zeylanicum, Salvia sclarea, Citrus aurantifolia, Melaleuca alternifolia, Citrus aurantium, Citrus bergamia, Pogostemon pathchouli, Cedrus atlantica, Jasminum officinale, Juniperus communis, Abelmoschus moschatus, Cyperus scariosus, Palargonium graveolens, Boswellia carterii, Rosa damascene, Veteveria zizanoides and Commiphora myrrha were evaluated. The essential oils of Cymbopogon winterians, Mentha piperita, Cinnamomum zeylanicum, Melaleuca alternifolia and Eucalyptus globulus were proved to be most effective against the fungus Trichosporon ovoides. PMID:24031963
Biological control of Melaleuca quinquenervia: an Everglades invader
Technology Transfer Automated Retrieval System (TEKTRAN)
A massive effort is underway to restore the Florida Everglades, mainly by re-engineering hydrology to supply more water to the system at appropriate times of the year. However, correcting water flow patterns alone will not restore the associated plant communities due to habitat-transforming effects...
Composition, and antimicrobial and remarkable antiprotozoal activities of the essential oil of rhizomes of Aframomum sceptrum K. Schum. (Zingiberaceae).
Cheikh-Ali, Zakaria; Adiko, Marcelline; Bouttier, Sylvie; Bories, Christian; Okpekon, Timothée; Poupon, Erwan; Champy, Pierre
The essential oil from the rhizomes of Aframomum sceptrum (Zingiberaceae) was analyzed by GC/MS, and its major constituents were found to be β-pinene (12.7%), caryophyllene oxide (10.0%), and cyperene (6.0%). The oil was also evaluated for antimicrobial activities, in comparison with β-pinene, caryophyllene oxide, and the leaf essential oil of Melaleuca alternifolia (Myrtaceae). The A. sceptrum essential oil exhibited bacteriostatic activity against the Gram-positive bacteria Bacillus subtilis, Staphylococcus epidermidis, and S. aureus, but not against Gram-negative bacteria. Moreover, it showed mild fungicidal activity against Candida albicans and Aspergillus fumigates, and remarkable antiprotozoal activity against Trypanosoma brucei brucei (MLC of 1.51 μl/ml) and Trichomonas vaginalis (IC(50) of 0.12±0.02 and MLC of 1.72 μl/ml). PMID:21480511
Screening of medicinal and edible plants in Okinawa, Japan, for enhanced proliferative and collagen synthesis activities in NB1RGB human skin fibroblast cells.
Takahashi, Makoto; Asikin, Yonathan; Takara, Kensaku; Wada, Koji
To identify plants with bioactive potential for skin care, methanol extracts of 56 plant parts from 47 medical and edible plants cultivated in Okinawa were tested for their proliferative effects on NB1RGB skin fibroblast cells. Extracts from six plants, Bischofia javanica, Colocasia esculenta, Melaleuca alternifolia, Piper angustifolia, Jasminum sambac, and Curcuma longa, showed higher NB1RGB cell proliferation activity (>10%) than the control, at various concentrations. Among the six extracts, only the C. longa extract caused an increase in collagen synthesis in NB1RGB cells, as compared to treatment with the positive control, ascorbic acid (AsA). Expression of the collagen synthesis marker, transforming growth factor-β1, was higher after treatment with the C. longa extract than with AsA. PMID:23221723
Antimicrobial effect against different bacterial strains and bacterial adaptation to essential oils used as feed additives
Melo, Antonio Diego Brandão; Amaral, Amanda Figueiredo; Schaefer, Gustavo; Luciano, Fernando Bittencourt; de Andrade, Carla; Costa, Leandro Batista; Rostagno, Marcos Horácio
The aim of this study was to evaluate the antimicrobial activity and determine the minimum bactericidal concentration (MBC) of the essential oils derived from Origanum vulgare (oregano), Melaleuca alternifolia (tea tree), Cinnamomum cassia (cassia), and Thymus vulgaris (white thyme) against Salmonella Typhimurium, Salmonella Enteritidis, Escherichia coli, Staphylococcus aureus and Enterococcus faecalis. The study also investigated the ability of these different bacterial strains to develop adaptation after repetitive exposure to sub-lethal concentrations of these essential oils. The MBC of the essential oils studied was determined by disc diffusion and broth dilution methods. All essential oils showed antimicrobial effect against all bacterial strains. In general, the development of adaptation varied according to the bacterial strain and the essential oil (tea tree > white thyme > oregano). Therefore, it is important to use essential oils at efficient bactericidal doses in animal feed, food, and sanitizers, since bacteria can rapidly develop adaptation when exposed to sub-lethal concentrations of these oils. PMID:26424908
Toxicity of essential and non-essential oils against the chewing louse, Bovicola (Werneckiella) ocellatus.
Talbert, R; Wall, R
The toxicity of six plant essential oils to the chewing louse, Bovicola (Werneckiella) ocellatus collected from donkeys, was examined in laboratory bioassays. The oils examined were: tea-tree (Melaleuca alternifolia), lavender (Lavandula angustifolia), peppermint (Mentha piperita), eucalyptus (Eucalyptus globulus Labillardiere), clove bud (Eugenia caryophyllata) and camphor (Cinnamomum camphora). All except camphor oil showed high levels of toxicity, with significant dose-dependent mortality and an LC(50) at concentrations of below 2% (v/v). Hundred percent mortality was achieved at concentrations of 5-10% (v/v). Two essential oil components: eugenol and (+)-terpinen-4-ol showed similar levels of toxicity. The data suggest that these botanical products may offer environmentally and toxicologically safe, alternative veterinary pediculicides for the control of ectoparasitic lice. PMID:22177577
Antimicrobial effect against different bacterial strains and bacterial adaptation to essential oils used as feed additives.
Melo, Antonio Diego Brandão; Amaral, Amanda Figueiredo; Schaefer, Gustavo; Luciano, Fernando Bittencourt; de Andrade, Carla; Costa, Leandro Batista; Rostagno, Marcos Horácio
The aim of this study was to evaluate the antimicrobial activity and determine the minimum bactericidal concentration (MBC) of the essential oils derived from Origanum vulgare (oregano), Melaleuca alternifolia (tea tree), Cinnamomum cassia (cassia), and Thymus vulgaris (white thyme) against Salmonella Typhimurium, Salmonella Enteritidis, Escherichia coli, Staphylococcus aureus and Enterococcus faecalis. The study also investigated the ability of these different bacterial strains to develop adaptation after repetitive exposure to sub-lethal concentrations of these essential oils. The MBC of the essential oils studied was determined by disc diffusion and broth dilution methods. All essential oils showed antimicrobial effect against all bacterial strains. In general, the development of adaptation varied according to the bacterial strain and the essential oil (tea tree > white thyme > oregano). Therefore, it is important to use essential oils at efficient bactericidal doses in animal feed, food, and sanitizers, since bacteria can rapidly develop adaptation when exposed to sub-lethal concentrations of these oils. PMID:26424908
The in vitro and in vivo antiviral properties of combined monoterpene alcohols against West Nile virus infection.
Pliego Zamora, Adriana; Edmonds, Judith H; Reynolds, Maxwell J; Khromykh, Alexander A; Ralph, Stephen J
West Nile Virus (WNV) is a mosquito-borne flavivirus that can cause neuroinvasive disease in humans and animals for which no therapies are currently available. We studied an established combination of monoterpene alcohols (CMA) derived from Melaleuca alternifolia, against WNV infection. The in vitro results show that CMA exhibits virucidal activity, as well as reduces the viral titres and percentage of infected cells. The antiviral mechanism of action of CMA was studied. We found that CMA did not alter the intracellular pH, neither induced apoptosis, but did induce cell cycle arrest in the G0/G1-phase although that was not the antiviral mechanism. Furthermore, we tested CMA in vivo using IRF 3(-)(/)(-)/7(-/-)mice and it was found that CMA treatment significantly delayed morbidity due to WNV infection, reduced the loss of body weight and reduced the viral titres in brain. These findings suggest that CMA could be a therapeutic agent against WNV infection. PMID:27152479
Cumulative mortality of Aedes aegypti larvae treated with compounds.
Torres, Sandra Maria; Cruz, Nadine Louise Nicolau da; Rolim, Vitor Pereira de Matos; Cavalcanti, Maria Inês de Assis; Alves, Leucio Câmara; Silva Júnior, Valdemiro Amaro da
OBJECTIVE To evaluate the larvicidal activity of Azadirachta indica, Melaleuca alternifolia, carapa guianensis essential oils and fermented extract of Carica papaya against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae). METHODS The larvicide test was performed in triplicate with 300 larvae for each experimental group using the third larval stage, which were exposed for 24h. The groups were: positive control with industrial larvicide (BTI) in concentrations of 0.37 ppm (PC1) and 0.06 ppm (PC2); treated with compounds of essential oils and fermented extract, 50.0% concentration (G1); treated with compounds of essential oils and fermented extract, 25.0% concentration (G2); treated with compounds of essential oils and fermented extract, 12.5% concentration (G3); and negative control group using water (NC1) and using dimethyl (NC2). The larvae were monitored every 60 min using direct visualization. RESULTS No mortality occurred in experimental groups NC1 and NC2 in the 24h exposure period, whereas there was 100% mortality in the PC1 and PC2 groups compared to NC1 and NC2. Mortality rates of 65.0%, 50.0% and 78.0% were observed in the groups G1, G2 and G3 respectively, compared with NC1 and NC2. CONCLUSIONS The association between three essential oils from Azadirachta indica, Melaleuca alternifolia, Carapa guianensis and fermented extract of Carica papaya was efficient at all concentrations. Therefore, it can be used in Aedes aegypti Liverpool third larvae stage control programs. PMID:25119939
Cumulative mortality of Aedes aegypti larvae treated with compounds
Torres, Sandra Maria; da Cruz, Nadine Louise Nicolau; Rolim, Vitor Pereira de Matos; Cavalcanti, Maria Inês de Assis; Alves, Leucio Câmara; da Silva, Valdemiro Amaro
OBJECTIVE To evaluate the larvicidal activity of Azadirachta indica, Melaleuca alternifolia, carapa guianensis essential oils and fermented extract of Carica papaya against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae). METHODS The larvicide test was performed in triplicate with 300 larvae for each experimental group using the third larval stage, which were exposed for 24h. The groups were: positive control with industrial larvicide (BTI) in concentrations of 0.37 ppm (PC1) and 0.06 ppm (PC2); treated with compounds of essential oils and fermented extract, 50.0% concentration (G1); treated with compounds of essential oils and fermented extract, 25.0% concentration (G2); treated with compounds of essential oils and fermented extract, 12.5% concentration (G3); and negative control group using water (NC1) and using dimethyl (NC2). The larvae were monitored every 60 min using direct visualization. RESULTS No mortality occurred in experimental groups NC1 and NC2 in the 24h exposure period, whereas there was 100% mortality in the PC1 and PC2 groups compared to NC1 and NC2. Mortality rates of 65.0%, 50.0% and 78.0% were observed in the groups G1, G2 and G3 respectively, compared with NC1 and NC2. CONCLUSIONS The association between three essential oils from Azadirachta indica, Melaleuca alternifolia, Carapa guianensis and fermented extract of Carica papaya was efficient at all concentrations. Therefore, it can be used in Aedes aegypti Liverpool third larvae stage control programs. PMID:25119939
La Torre, A; Caradonia, F; Gianferro, M; Molinu, M G; Battaglia, V
The requirement of environmental protection and food safety is perceived with always major interest by public opinion and it is consistent with European Union legislation on the sustainable use of pesticides (Directive 2009/128/EC). This directive requires member states to promote low pesticide-input, giving priority to non-chemical methods and low risk plant protection products. In order to contribute to the achievement of these objectives antifungal activity of natural substances, characterized by a good toxicological and ecotoxicological profile, was tested. Essential oil of Melaleuca alternifolia, essential oil of Syzygium aromaticum and extract from Mimosa tenuiflora were tested against Alternaria alternata, Botrytis cinerea and Fusarium oxysporum f. sp. lycopersici (races 1 and 2). In vitro tests involved determination of radial growth of the colonies of fungi in the presence of varying concentrations of tested products in agar media and determination of germination percentage in the presence of tested product at various concentrations. The products based on essential oil of M. alternifolia were also tested in vivo on tomato fruits wounded and artificially inoculated with A. alternata or with B. cinerea. The in vitro tests showed the antifungal activity of both essential oils instead the extract from M. tenuiflora exhibited poor antifungal activity and only against A. alternata and B. cinerea. The results on tomato fruits showed inhibition of grey mould and black mould by essential oil of M. alternifolia. The antifungal activity increased with increasing concentrations. In conclusion, the obtained results in the present study showed promising prospects for the utilisation of investigated products to reduce the using of antifungal chemicals and to achieve a more sustainable use of pesticides. PMID:26080478
Collaborative efforts for managing Melaleuca in the Ciénega de Zapata, Cuba
Technology Transfer Automated Retrieval System (TEKTRAN)
The Ciénega de Zapata Biosphere Reserve is the largest protected area not only in Cuba but also throughout the Caribbean. This swamp ecosystem is characterized by a high biodiversity that comprises several endemic birds, reptiles and invertebrates and is visited by 65 species of birds during their a...
Natural enemy density and soil type influence growth and survival of Melaleuca quinquenervia seedlings
Technology Transfer Automated Retrieval System (TEKTRAN)
Multiple insects are commonly introduced as biological control agents to reduce growth and spread of invasive plants. Little is known about the species-specific contributions of co-existing agents, and about insect density needed to control invasive plants. We investigated the effects of insect type...
Chemical and biological evaluation of the essential oils of different Melaleuca species.
Farag, R S; Shalaby, A S; El-Baroty, G A; Ibrahim, N A; Ali, M A; Hassan, E M
The essential oils of the fresh leaves of M. ericifolia, M. leucadendron, M. armillaris and M. styphelioides were isolated by a hydrodistillation method and analysed by a gas chromatography/mass spectrometry (GC/MS) technique. The essential oil of M. ericifolia contained methyl eugenol (96.84%) as a major constituent, whereas M. leucadendron was rich in 1,8-cineole (64.30%). The essential oil of M. armillaris was rich in 1,8-cineole (33.93%) followed by terpinen-4-ol (18.79%), whereas M. styphelioides was rich in caryophyllene oxide (43.78%) and (-) spathulenol (9.65%). The essential oils of these species possessed antimicrobial and antifungal activities. M. ericifolia exhibited the highest inhibitory effects against Bacillus subtiles and Aspergillus niger. The antiviral activities of the essential oils against Herpes simplex virus type 1 (HSV-1) were studied in African green monkey kidney cells (Vero) by a plaque reduction assay. The volatile oil of M. armillaris was more effective as a virucidal (up to 99%) than that of M. leucadendron (92%) and M. ericifolia (91.5%). The effects of the essential oils on the antioxidant system status in carbon tetrachloride treated animals were studied. The essential oil of M. armillaris exhibited a marked antioxidant effect, it improved vitamin E, vitamin C and superoxide dismutase parameters so it can be used as a free radical suppressor. PMID:14750197
Comparison of antimicrobial activity of essential oils, plant extracts and methylparaben in cosmetic emulsions: 2 months study.
Herman, Anna
The aim of the study was to compare the preservative effectiveness of plant extracts (Matricaria chamomilla, Aloe vera, Calendula officinalis) and essential oils (Lavandulla officinalis, Melaleuca alternifolia, Cinnamomum zeylanicum) with methylparaben in cosmetic emulsions against skin microflora during 2 months of application by volunteers. Cosmetic emulsions with extracts (2.5 %), essential oils (2.5 %), methylparaben (0.4 %) or placebo were tested by 40 volunteers during 2 months of treatment. In order to determine microbial purity of the emulsions, the samples were taken after 0, 2, 4, 6 and 8 weeks of application. Throughout the trial period it was revealed that only cinnamon oil completely inhibited the growth of bacteria, yeast and mould, as compared to all other essential oils, plant extracts and methylparaben in the tested emulsions. This result shows that cinnamon oil could successfully replace the use of methylparaben in cosmetics, at the same time ensuring microbiological purity of a cosmetic product under its in-use and storage conditions. PMID:24891745
[Quality evaluation of essential oils].
Mori, Masahiro; Ikeda, Norikazu; Kato, Yoshiko; Minamino, Miki; Watabe, Kazuhito
Essential oils on the market were analyzed using GC-MS and the main ingredients of each essential oil were quantified. Analysis of the essential oil of Lavandula officinalis (lavender oil) showed that each sample had a different ratio of the contents of main ingredients, such as linalool, linalyl acetate, and camphor. In addition, some commercial lavender oils were analyzed by GC-MS for comparison with the Lavandula flagrans (lavandin oil) and the reference standard. As a result of this analysis, although the components of almost all commercial lavender oils were approximately the same as those of the reference standard, there were a few products that contained more than 0.5% of the amount of camphor in lavandin oil. This suggests that some lavender oil samples are mixed with lavandin oil to lower the price. Commercial essential oils of Melaleuca alternifolia (teatree oil) and Mentha piperita (peppermint oil) were also analyzed by GC-MS. Each of the peppermint oil samples had a different ratio in the content of its main ingredient. With respect to teatree oils, the amount of terpinens in each sample differed. These results led to concern about the efficacy of essential oils. For achieve the expected efficacy of essential oils, correct information on their ingredients should be available and quality control using instrumental analysis should be introduced. PMID:11905050
Laboratory evaluation of aromatic essential oils from thirteen plant species as candidate repellents against Leptotrombidium chiggers (Acari: Trombiculidae), the vector of scrub typhus.
Eamsobhana, Praphathip; Yoolek, Adisak; Kongkaew, Wittaya; Lerdthusnee, Kriangkrai; Khlaimanee, Nittaya; Parsartvit, Anchana; Malainual, Nat; Yong, Hoi-Sen
Scrub typhus, a rickettsial disease transmitted by several species of Leptotrombidium chiggers (larvae), is endemic in many areas of Asia. The disease is best prevented by the use of personal protective measures, including repellents. In this study commercially produced aromatic, essential oils of 13 plant species and ethanol (control) were tested in the laboratory for repellency against host-seeking chiggers of Leptotrombidium imphalum Vercammen-Grandjean and Langston (Acari: Trombiculidae). A rapid, simple and economic in vitro test method was used by exposing the chigger for up to 5 min. Repellency was based on relative percentages of chiggers attracted to test and control substances. Four of the 13 essential oils showed promise as effective repellent against L. imphalum chiggers. Syzygium aromaticum (clove) oil exhibited 100% repellency at 5% concentration (dilution with absolute ethanol), whereas Melaleuca alternifolia (tea tree) oil exhibited 100% repellency at 40% concentration. Undiluted oils of Zingiber cassamunar (plai) and Eucalyptus globules (blue gum) exhibited 100% repellency. Of the remaining nine essential oils, only 100% Pelargonium graveolens (geranium) exhibited >50% repellency (viz. 57%). Styrax torkinensis (benzoin) oil did not exhibit any repellency. These findings show that several aromatic, essential oils of plants may be useful as chigger repellent for the prevention of scrub typhus. Syzygium aromaticum oil may be safer and more economical to prevent chigger attacks than commercially available synthetic chemicals, such as DEET that may have harmful side effects. PMID:19009361
Essential oils and herbal extracts as antimicrobial agents in cosmetic emulsion.
Herman, Anna; Herman, Andrzej Przemysław; Domagalska, Beata Wanda; Młynarczyk, Andrzej
The cosmetic industry adapts to the needs of consumers seeking to limit the use of preservatives and develop of preservative-free or self-preserving cosmetics, where preservatives are replaced by raw materials of plant origin. The aim of study was a comparison of the antimicrobial activity of extracts (Matricaria chamomilla, Aloe vera, Calendula officinalis) and essential oils (Lavandulla officinallis, Melaleuca alternifolia, Cinnamomum zeylanicum) with methylparaben. Extracts (2.5 %), essential oils (2.5 %) and methylparaben (0.4 %) were tested against Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, Candida albicans ATCC 14053. Essentials oils showed higher inhibitory activity against tested microorganism strain than extracts and methylparaben. Depending on tested microorganism strain, all tested extracts and essential oils show antimicrobial activity 0.8-1.7 and 1-3.5 times stronger than methylparaben, respectively. This shows that tested extracts and essential oils could replace use of methylparaben, at the same time giving a guarantee of microbiological purity of the cosmetic under its use and storage. PMID:24426114
Exploring the Anti-Burkholderia cepacia Complex Activity of Essential Oils: A Preliminary Analysis
Lo Nostro, Antonella; Calonico, Carmela; Perrin, Elena; Chiellini, Carolina; Fondi, Marco; Mengoni, Alessio; Vannacci, Alfredo; Bilia, Anna Rita; Gori, Luigi
In this work we have checked the ability of the essential oils extracted from six different medicinal plants (Eugenia caryophyllata, Origanum vulgare, Rosmarinus officinalis, Lavandula officinalis, Melaleuca alternifolia, and Thymus vulgaris) to inhibit the growth of 18 bacterial type strains belonging to the 18 known species of the Burkholderia cepacia complex (Bcc). These bacteria are opportunistic human pathogens that can cause severe infection in immunocompromised patients, especially those affected by cystic fibrosis (CF), and are often resistant to multiple antibiotics. The analysis of the aromatograms produced by the six oils revealed that, in spite of their different chemical composition, all of them were able to contrast the growth of Bcc members. However, three of them (i.e., Eugenia caryophyllata, Origanum vulgare, and Thymus vulgaris) were particularly active versus the Bcc strains, including those exhibiting a high degree or resistance to ciprofloxacin, one of the most used antibiotics to treat Bcc infections. These three oils are also active toward both environmental and clinical strains (isolated from CF patients), suggesting that they might be used in the future to fight B. cepacia complex infections. PMID:24701243
Screening of some essential oils against Trichosporon species.
Uniyal, Veena; Saxena, Seema; Bhatt, R P
White Piedra is a superficial mycoses characterized by nodules on the hair shaft, caused by the basidiomycetous yeast Trichosporon species. In this study 25 essential oils were extracted and screened against two Trichosporon species i.e. Trichosporon asahii and Trichosporon cutaneum. Both these fungi procured from MTCC Chandigarh were maintained on yeast malt agar plates and tubes at 25 degrees C. Two screening methods viz., agar well diffusion assay and minimum inhibitory concentration were adopted for the study. The results showed that the maximum anti-yeast activity against T. asahii and T. cutaneum was demonstrated by oil of Mentha piperita showing full inhibition of both the fungi, Melaleuca alternifolia with an inhibition zone of 45 and 40 mm, Cymbopogon winterians with inhibition zone of 45 and 45 mm and Cymbopogon flexuosus with 35 and 30 mm inhibition zones. The oil of Trachyspermum ammi exhibited 10 and 20 mm, Abelmoschus moschatus exhibited 30 and 20 mm, Salvia sclarea showed 20 and 18 mm and Jasminum officinale exhibited 25 and 15 mm inhibition zones showing moderate activity. The oil of Cyperus scariosus, Pogostemon patchouli and Rosa damascene showed no inhibition zone against both the fungi while Vetiveria zizanoides exhibited no inhibition in case of T. asahii and inhibition zone of 10 mm in case of T. cutaneum demonstrating comparatively low activity against both the fungi. These results support that the essential oils can be used to cure superficial mycoses and these oils may have significant role as pharmaceuticals and preservatives. PMID:24006802
Medicinal plant treatments for fleas and ear problems of cats and dogs in British Columbia, Canada.
Lans, Cheryl; Turner, Nancy; Khan, Tonya
Research conducted in 2003/2004 documented and validated (in a non-experimental way) ethnoveterinary medicines used by small-scale, organic livestock farmers in British Columbia (BC), Canada. Interviews were conducted with 60 participants who were organic farmers or holistic medicinal/veterinary practitioners. A workshop was held with selected participants to discuss the plant-based treatments. This paper reports on the medicinal plants used for fleas in cats and dogs. Fleas and flies are treated with Artemisia vulgaris L. (Asteraceae), Citrus x limon (L.), Juniperus communis L. var. depressa Pursh. (Cupressaceae), Lavandula officinalis L. (Labiatae), Melissa officinalis L. (Lamiaceae), and Thuja plicata Donn ex D. Don (Cupressaceae). All of the plants used have insecticidal activity. Ear problems are treated with Achillea millefolium L., Calendula officinalis L., and Helichrysum angustifolium (Roth.) G. Don. (Asteraceae), Allium sativum L. (Alliaceae), Berberis aquifolium Pursh./Mahonia aquifolium (Berberidaceae), Glycyrrhiza glabra L. (Fabaceae), Lobelia inflata L. (Campanulaceae), Matricaria recutita L., Melaleuca alternifolia L. (Myrtaceae), Origanum vulgare L. (Labiatae), Ricinus communis L. (Euphorbiaceae), Syzygium aromaticum (L.) Merr. & L. M. Perry (Myrtaceae), Thymus vulgaris L. (Lamiaceae), and Verbascum thapsus L. (Scrophulariaceae). PMID:18563443
Antifungal Effect of Essential Oils against Fusarium Keratitis Isolates.
Homa, Mónika; Fekete, Ildikó Pálma; Böszörményi, Andrea; Singh, Yendrembam Randhir Babu; Selvam, Kanesan Panneer; Shobana, Coimbatore Subramanian; Manikandan, Palanisamy; Kredics, László; Vágvölgyi, Csaba; Galgóczy, László
The present study was carried out to investigate the antifungal effects of Cinnamomum zeylanicum, Citrus limon, Juniperus communis, Eucalyptus citriodora, Gaultheria procumbens, Melaleuca alternifolia, Origanum majorana, Salvia sclarea, and Thymus vulgaris essential oils against Fusarium species, the most common etiologic agents of filamentous fungal keratitis in South India. C. zeylanicum essential oil showed strong anti-Fusarium activity, whereas all the other tested essential oils proved to be less effective. The main component of C. zeylanicum essential oil, trans-cinnamaldehyde, was also tested and showed a similar effect as the oil. The in vitro interaction between trans-cinnamaldehyde and natamycin, the first-line therapeutic agent of Fusarium keratitis, was also investigated; an enhanced fungal growth inhibition was observed when these agents were applied in combination. Light and fluorescent microscopic observations revealed that C. zeylanicum essential oil/trans-cinnamaldehyde reduces the cellular metabolism and inhibits the conidia germination. Furthermore, necrotic events were significantly more frequent in the presence of these two compounds. According to our results, C. zeylanicum essential oil/trans-cinnamaldehyde provides a promising basis to develop a novel strategy for the treatment of Fusarium keratitis. PMID:26227503
Linalool Affects the Antimicrobial Efficacy of Essential Oils.
Herman, Anna; Tambor, Krzysztof; Herman, Andrzej
The high concentrations of essential oils are generally required to receive microbial purity of the products (cosmetics, medicine). On the other hand, their application due to the high concentration of essential oils may be limited by changes in organoleptic and textural quality of the products, as well as they cause irritation and allergies in users. Addition of linalool to essential oil may significantly enhance its antimicrobial effectiveness and reduce their concentrations in products, taking advantage of their synergistic and additive effects. The aim of the study was to compare antimicrobial activity of essential oil alone and in combination with linalool. The antimicrobial activity of the essential oil of Thymus vulgaris, Juniperus communis, Pelargonium graveolens, Citrus bergamia, Citrus grandis, Lavandula angustifolia, Cinnamomum zeylanicum, Melaleuca alternifolia, Syzygium aromaticum, linalool and their combination was investigated against bacteria and fungi using the disc diffusion method. The addition of linalool to S. aromaticum oil in a synergistic manner enhanced its antimicrobial efficacy against P. aeruginosa and A. brasiliensis. Moreover, the additive interaction between this oil and linalool was observed against S. aureus, E. coli and C. albicans. It was also found that linalool in an additive manner increased the antimicrobial effectiveness of T. vulgaris oil against P. aeruginosa. The antimicrobial properties of mixture of essential oils with their active constituents may be used for creating new strategies to maintain microbiological purity of products. PMID:26553262
Rhamnolipids as emulsifying agents for essential oil formulations: antimicrobial effect against Candida albicans and methicillin-resistant Staphylococcus aureus.
Haba, Ester; Bouhdid, Samira; Torrego-Solana, Noelia; Marqués, A M; Espuny, M José; García-Celma, M José; Manresa, Angeles
This work examines the influence of essential oil composition on emulsification with rhamnolipids and their use as therapeutic antimicrobial agents against two opportunistic pathogens, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. Rhamnolipids, produced by Pseudomonas aeruginosa, with waste frying oil as the carbon source, were composed of eight rhamnolipid homologues. The rhamnolipid mixture was used to produce emulsions containing essential oils (EOs) of Melaleuca alternifolia, Cinnamomum verum, Origanum compactum and Lavandula angustifolia using the titration method. Ternary phase diagrams were designed to evaluate emulsion stability, which differed depending on the essential oil. The in vitro antimicrobial activity of the EOs alone and the emulsions was evaluated. The antimicrobial activity presented by the essential oils alone increased with emulsification. The surface properties of rhamnolipids contribute to the positive dispersion of EOs and thus increase their availability and antimicrobial activity against C. albicans and S. aureus. Therefore, rhamnolipid-based emulsions represent a promising approach to the development of EO delivery systems. PMID:25269010
Exotic tree leaf litter accumulation and mass loss dynamics compared with two sympatric native species in South Florida, USA
Technology Transfer Automated Retrieval System (TEKTRAN)
The invasive tree Melaleuca quinquenervia (melaleuca) forms dense forests in ecologically sensitive habitats, including portions of the Florida Everglades. Within these stands, forest understories are characterized by low species diversity and a dense layer of accumulated melaleuca litter. However...
Sequencing and expression analysis of salt-responsive miRNAs and target genes in the halophyte smooth cordgrass (Spartina alternifolia Loisel).
Zandkarimi, Hana; Bedre, Renesh; Solis, Julio; Mangu, Venkata; Baisakh, Niranjan
MicroRNAs have been shown to be involved in regulating plant's response to environmental stresses, including salinity. There is no report yet on the miRNA-mediated posttranscriptional regulation of salt stress response of a grass halophyte by miRNAs. Here we report on the deep-sequencing followed by expression validation through (s)qRT-PCR of a selected set of salt-responsive miRNAs and their targets of the salt marsh monocot halophyte smooth cordgrass (Spartina alterniflora Loisel). Expression kinetics study of 12 miRNAs showed differential up/down-regulation in leaf and root tissues under salinity. Induction of expression of six putative novel microRNAs with high read counts in the sequence library suggested that the halophyte grass may possess different/novel gene posttranscriptional regulation of its salinity adaptation. Similarly, expression analysis of target genes of four selected miRNAs showed temporal and spatial variation in the up/down-regulation of their transcript accumulation under salt stress. The expression levels of miRNAs and their respective targets were coherent, non-coherent, or semi-coherent type. Understanding the gene regulation mechanism(s) at the miRNA level will broaden our fundamental understanding of the biology of the salt stress tolerance of the halophyte and provide novel positive regulators of salt stress tolerance for downstream research. PMID:25976974
An evaluation of the impact of Melaleuca quinquenervia invasion and managment on plant community structure after fire.
Technology Transfer Automated Retrieval System (TEKTRAN)
The successful management of invasive species can be particularly difficult in natural areas that depend on disturbances such as fire to maintain community structure and function. In these systems, fire-adapted invasive species may disproportionally benefit from post-fire resource availability, inc...
The potential of selected Australian medicinal plants with anti-Proteus activity for the treatment and prevention of rheumatoid arthritis
Cock, I. E.; Winnett, V.; Sirdaarta, J.; Matthews, B.
Background: A wide variety of herbal medicines are used in indigenous Australian traditional medicinal systems to treat rheumatoid arthritis (RA) and inflammation. The current study was undertaken to test the ability of a panel of Australian plants with a history of the ethnobotanical usage in the treatment of inflammation for the ability to block the microbial trigger of RA. Materials and Methods: One hundred and six extracts from 40 plant species were investigated for the ability to inhibit the growth of the bacterial trigger of RA (Proteus mirabilis). The extracts were tested for toxicity in the Artemia nauplii bioassay. The most potent inhibitor of P. mirabilis growth was further analyzed by reversed-phase high performance liquid chromatography (RP-HPLC) coupled to high accuracy time-of-flight (TOF) mass spectroscopy. Results: Sixty-five of the 106 extracts tested (61.3%) inhibited the growth of P. The Aleurites moluccanus, Datura leichardtii, Eucalyptus major, Leptospermum bracteata, L. juniperium, Macadamia integriflora nut, Melaleuca alternifolia, Melaleuca quinquenervia, Petalostigma pubescens, P. triloculorae, P. augustifolium, Scaevola spinescens, Syzygiumaustrale, and Tasmannia lanceolata extracts were determined to be the most effective inhibitors of P. mirabilis growth, with minimum inhibitory concentration (MIC) values generally significantly below 1000 μg/ml. T. lanceolata fruit extracts were the most effective P. mirabilis growth inhibitors, with a MIC values of 11 and 126 μg/ml for the methanolic and aqueous extracts, respectively. Subsequent analysis of the T. lanceolata fruit extracts by RP-HPLC coupled to high-resolution TOF mass spectroscopy failed to detect resveratrol in either T. lanceolata fruit extract. However, the resveratrol glycoside piceid and 2 combretastatin stilbenes (A-1 and A-4) were detected in both T. lanceolata fruit extracts. With the exception of the Eucalyptus and Syzygium extracts, all extracts exhibiting Proteus
Evaluation of tea tree oil for controlling Rhipicephalus microplus in dairy cows.
Pazinatto Boito, Jhonatan; Santos, Roberto C; Vaucher, Rodrigo A; Raffin, Renata; Machado, Gustavo; Tonin, Alexandre A; Da Silva, Aleksandro S
Our research aimed to test the effects of Melaleuca alternifolia oil (pure and in nanocapsules) in the control of Rhipicephalus microplus in dairy cattle. For this purpose, the in vivo studies used 15 cows distributed in three different groups with the same number of animals. Five cows remained untreated (Group A), representing the control group; other five cows were sprayed with TTO (at 5%) in its pure form (Group B); and five cows were sprayed with nanocapsules of TTO (at 0.75%) (Group C). On days 1 and 4 post-treatments (PT), all cows had their ticks counted. On day 1 PT, two ticks from each cow were collected to evaluate the effect of the treatment on ticḱs reproduction (in vitro assays). The pure form of TTO caused a significant reduction (P<0.05) in the number of ticks from the Group B compared to the Group A on day 4 PT. However, there was no significant difference in the number of ticks on cows from Groups A and C after treatment (P>0.05). Treatment with TTO in nanocapsules (Group C) interfered with R. microplus reproduction, leading to lower oviposition by female ticks and hatchability (34.5% of efficacy). On the other hand, TTO oil (Group B) did not interfere on ticḱs reproduction, i.e. showed higher hatchability than the control group. Therefore, it is possible to conclude that pure TTO has an acaricidal effect in dairy cows, in addition to an effect on ticḱs reproduction when used its nanocapsulated form. PMID:27369577
In Chemico Evaluation of Tea Tree Essential Oils as Skin Sensitizers: Impact of the Chemical Composition on Aging and Generation of Reactive Species.
Avonto, Cristina; Chittiboyina, Amar G; Wang, Mei; Vasquez, Yelkaira; Rua, Diego; Khan, Ikhlas A
Tea tree oil (TTO) is an essential oil obtained from the leaves of Melaleuca alternifolia, M. linariifolia, or M. dissitiflora. Because of the commercial importance of TTO, substitution or adulteration with other tea tree species (such as cajeput, niaouli, manuka, or kanuka oils) is common and may pose significant risks along with perceived health benefits. The distinctive nature, qualitative and quantitative compositional variation of these oils, is responsible for the various pharmacological as well as adverse effects. Authentic TTOs (especially aged ones) have been identified as potential skin sensitizers, while reports of adverse allergic reactions to the other tea trees essential oils are less frequent. Chemical sensitizers are usually electrophilic compounds, and in chemico methods have been developed to identify skin allergens in terms of their ability to bind to biological nucleophiles. However, little information is available on the assessment of sensitization potential of mixtures, such as essential oils, due to their complexity. In the present study, 10 "tea tree" oils and six major TTO constituents have been investigated for their sensitization potential using a fluorescence in chemico method. The reactivity of authentic TTOs was found to correlate with the age of the oils, while the majority of nonauthentic TTOs were less reactive, even after aging. Further thio-trapping experiments with DCYA and characterization by UHPLC-DAD-MS led to the identification of several possible DCYA-adducts which can be used to deduce the structure of the candidate reactive species. The major TTO components, terpinolene, α-terpinene, and terpinene-4-ol, were unstable under accelerated aging conditions, which led to the formation of several DCYA-adducts. PMID:27286037
Insecticidal and repellent effects of tea tree and andiroba oils on flies associated with livestock.
Klauck, V; Pazinato, R; Stefani, L M; Santos, R C; Vaucher, R A; Baldissera, M D; Raffin, R; Boligon, A; Athayde, M; Baretta, D; Machado, G; DA Silva, A S
This study aimed to evaluate the insecticidal and repellent effects of tea tree, Melaleuca alternifolia (Myrtales: Myrtaceae), and andiroba, Carapa guianensis (Sapindales: Meliaceae), essential oils on two species of fly. For in vitro studies, free-living adult flies were captured and reared in the laboratory. To evaluate the insecticidal effects of the oils, adult flies of Haematobia irritans (L.) and Musca domestica L. (both: Diptera: Muscidae) were separated by species in test cages (n = 10 per group), and subsequently tested with oils at concentrations of 1.0% and 5.0% using a negative control to validate the test. Both oils showed insecticidal activity. Tea tree oil at a concentration of 5.0% was able to kill M. domestica with 100.0% efficacy after 12 h of exposure. However, the effectiveness of andiroba oil at a concentration of 5.0% was only 67.0%. The insecticidal efficacy (100.0%) of both oils against H. irritans was observed at both concentrations for up to 4 h. The repellency effects of the oils at concentrations of 5.0% were tested in vivo on Holstein cows naturally infested by H. irritans. Both oils demonstrated repellency at 24 h, when the numbers of flies on cows treated with tea tree and andiroba oil were 61.6% and 57.7%, respectively, lower than the number of flies on control animals. It is possible to conclude that these essential oils have insecticidal and repellent effects against the species of fly used in this study. PMID:25171605
Adverse and beneficial effects of plant extracts on skin and skin disorders.
Mantle, D; Gok, M A; Lennard, T W
Plants are of relevance to dermatology for both their adverse and beneficial effects on skin and skin disorders respectively. Virtually all cultures worldwide have relied historically, or continue to rely on medicinal plants for primary health care. Approximately one-third of all traditional medicines are for treatment of wounds or skin disorders, compared to only 1-3% of modern drugs. The use of such medicinal plant extracts for the treatment of skin disorders arguably has been based largely on historical/anecdotal evidence, since there has been relatively little data available in the scientific literature, particularly with regard to the efficacy of plant extracts in controlled clinical trials. In this article therefore, adverse and beneficial aspects of medicinal plants relating to skin and skin disorders have been reviewed, based on recently available information from the peer-reviewed scientific literature. Beneficial aspects of medicinal plants on skin include: healing of wounds and burn injuries (especially Aloe vera); antifungal, antiviral, antibacterial and acaricidal activity against skin infections such as acne, herpes and scabies (especially tea tree (Melaleuca alternifolia) oil); activity against inflammatory/immune disorders affecting skin (e.g. psoriasis); and anti-tumour promoting activity against skin cancer (identified using chemically-induced two-stage carcinogenesis in mice). Adverse effects of plants on skin reviewed include: irritant contact dermatitis caused mechanically (spines, irritant hairs) or by irritant chemicals in plant sap (especially members of the Ranunculaceae, Euphorbiaceae and Compositae plant families); phytophotodermatitis resulting from skin contamination by plants containing furocoumarins, and subsequent exposure to UV light (notably members of the Umbelliferae and Rutaceae plant families); and immediate (type I) or delayed hypersensitivity contact reactions mediated by the immune system in individuals sensitized to plants
"Singing in the Tube"--audiovisual assay of plant oil repellent activity against mosquitoes (Culex pipiens).
Adams, Temitope F; Wongchai, Chatchawal; Chaidee, Anchalee; Pfeiffer, Wolfgang
Plant essential oils have been suggested as a promising alternative to the established mosquito repellent DEET (N,N-diethyl-meta-toluamide). Searching for an assay with generally available equipment, we designed a new audiovisual assay of repellent activity against mosquitoes "Singing in the Tube," testing single mosquitoes in Drosophila cultivation tubes. Statistics with regression analysis should compensate for limitations of simple hardware. The assay was established with female Culex pipiens mosquitoes in 60 experiments, 120-h audio recording, and 2580 estimations of the distance between mosquito sitting position and the chemical. Correlations between parameters of sitting position, flight activity pattern, and flight tone spectrum were analyzed. Regression analysis of psycho-acoustic data of audio files (dB[A]) used a squared and modified sinus function determining wing beat frequency WBF ± SD (357 ± 47 Hz). Application of logistic regression defined the repelling velocity constant. The repelling velocity constant showed a decreasing order of efficiency of plant essential oils: rosemary (Rosmarinus officinalis), eucalyptus (Eucalyptus globulus), lavender (Lavandula angustifolia), citronella (Cymbopogon nardus), tea tree (Melaleuca alternifolia), clove (Syzygium aromaticum), lemon (Citrus limon), patchouli (Pogostemon cablin), DEET, cedar wood (Cedrus atlantica). In conclusion, we suggest (1) disease vector control (e.g., impregnation of bed nets) by eight plant essential oils with repelling velocity superior to DEET, (2) simple mosquito repellency testing in Drosophila cultivation tubes, (3) automated approaches and room surveillance by generally available audio equipment (dB[A]: ISO standard 226), and (4) quantification of repellent activity by parameters of the audiovisual assay defined by correlation and regression analyses. PMID:26412058
Antimicrobial activity of essential oils and carvacrol, and synergy of carvacrol and erythromycin, against clinical, erythromycin-resistant Group A Streptococci.
Magi, Gloria; Marini, Emanuela; Facinelli, Bruna
In the present study, we have evaluated the in vitro antibacterial activity of essential oils from Origanum vulgare, Thymus vulgaris, Lavandula angustifolia, Mentha piperita, and Melaleuca alternifolia against 32 erythromycin-resistant [Mininum Inhibitory Concentration (MIC) ≥1 μg/mL; inducible, constitutive, and efflux-mediated resistance phenotype; erm(TR), erm(B), and mef(A) genes] and cell-invasive Group A streptococci (GAS) isolated from children with pharyngotonsillitis in Italy. Over the past decades erythromycin resistance in GAS has emerged in several countries; strains combining erythromycin resistance and cell invasiveness may escape β-lactams because of intracellular location and macrolides because of resistance, resulting in difficulty of eradication and recurrent pharyngitis. Thyme and origanum essential oils demonstrated the highest antimicrobial activity with MICs ranging from 256 to 512 μg/mL. The phenolic monoterpene carvacrol [2-Methyl-5-(1-methylethyl) phenol] is a major component of the essential oils of Origanum and Thymus plants. MICs of carvacrol ranged from 64 to 256 μg/mL. In the live/dead assay several dead cells were detected as early as 1 h after incubation with carvacrol at the MIC. In single-step resistance selection studies no resistant mutants were obtained. A synergistic action of carvacrol and erythromycin was detected by the checkerboard assay and calculation of the Fractional Inhibitory Concentration (FIC) Index. A 2- to 2048-fold reduction of the erythromycin MIC was documented in checkerboard assays. Synergy (FIC Index ≤0.5) was found in 21/32 strains and was highly significant (p < 0.01) in strains where resistance is expressed only in presence of erythromycin. Synergy was confirmed in 17/23 strains using 24-h time-kill curves in presence of carvacrol and erythromycin. Our findings demonstrated that carvacrol acts either alone or in combination with erythromycin against erythromycin-resistant GAS and could potentially
Rehabilitation of invasive-tree degraded natural areas through biological control: a slow but steady process
Technology Transfer Automated Retrieval System (TEKTRAN)
Natural areas invaded by invasive exotic plants can develop into monocultures as native plants are displaced. The Australian tree Melaleuca quinquenervia (melaleuca) impacts natural areas in this manner in southern Florida. Environmental plasticity coupled with fire resistance, high reproductive po...
The genetic consequences of a demographic bottleneck in an introduced biological control insect
Technology Transfer Automated Retrieval System (TEKTRAN)
We examined phylogeography and population genetics of the melaleuca psyllid Boreioglycaspis melaleucae, which was introduced from Australia to Florida as a biological control agent of the invasive plant Melaleuca quinquenervia. We sampled psyllids in the native and introduced ranges as well as indi...
An Evaluation of Antifungal Agents for the Treatment of Fungal Contamination in Indoor Air Environments
Rogawansamy, Senthaamarai; Gaskin, Sharyn; Taylor, Michael; Pisaniello, Dino
Fungal contamination in indoor environments has been associated with adverse health effects for the inhabitants. Remediation of fungal contamination requires removal of the fungi present and modifying the indoor environment to become less favourable to growth. This may include treatment of indoor environments with an antifungal agent to prevent future growth. However there are limited published data or advice on chemical agents suitable for indoor fungal remediation. The aim of this study was to assess the relative efficacies of five commercially available cleaning agents with published or anecdotal use for indoor fungal remediation. The five agents included two common multi-purpose industrial disinfectants (Cavicide® and Virkon®), 70% ethanol, vinegar (4.0%−4.2% acetic acid), and a plant-derived compound (tea tree (Melaleuca alternifolia) oil) tested in both a liquid and vapour form. Tea tree oil has recently generated interest for its antimicrobial efficacy in clinical settings, but has not been widely employed for fungal remediation. Each antifungal agent was assessed for fungal growth inhibition using a disc diffusion method against a representative species from two common fungal genera, (Aspergillus fumigatus and Penicillium chrysogenum), which were isolated from air samples and are commonly found in indoor air. Tea tree oil demonstrated the greatest inhibitory effect on the growth of both fungi, applied in either a liquid or vapour form. Cavicide® and Virkon® demonstrated similar, although less, growth inhibition of both genera. Vinegar (4.0%–4.2% acetic acid) was found to only inhibit the growth of P. chrysogenum, while 70% ethanol was found to have no inhibitory effect on the growth of either fungi. There was a notable inhibition in sporulation, distinct from growth inhibition after exposure to tea tree oil, Virkon®, Cavicide® and vinegar. Results demonstrate that common cleaning and antifungal agents differ in their capacity to inhibit the
25 years of natural product R&D with New South Wales agriculture.
Southwell, Ian A
Following recent NSW Government restructuring, the Department of Agriculture now exists in a composite form along with Forestry, Fisheries and Minerals in the new NSW Department of Primary Industries. This paper outlines some of the highlights of secondary metabolite R&D accomplished in the 25 years since the essential oil research unit was transferred from the Museum of Applied Arts & Sciences, Sydney to NSW Agriculture's Wollongbar Agricultural Institute on the NSW north coast. The essential oil survey was continued, typing the Australian flora as a suitable source of isolates such as myrtenal (Astartea), myrtenol (Agonis), methyl chavicol(Ochrosperma), alpha-phellandren-8-ol (Prostanthera), methyl myrtenate (Darwinia), methyl geranate (Darwinia), kessane (Acacia), cis-dihydroagarofuran (Prosthanthera), protoanemonin (Clematis), isoamyl isovalerate (Micromyrtus), methyl cinnamate (Eucalyptus) and bornyl acetate (Boronia). Many of these components are used, or have potential use in the fragrance, flavour, medicinal plant or insect attraction fields. Two weeds toxic to livestock in the Central West of the State are also harvested commercially as medicinal plants. Measurement of hypericin concentrations in the various plant parts of St John's Wort (Hypericum perforatum) over two seasons has shown that the weed can be effectively managed by grazing sheep during the winter months when toxin levels are low. Syntheses of beta-carbolines tribulusterine and perlolyrine have shown that the former alkaloid was misidentified in the literature and hence not the toxic principle responsible for Tribulus staggers in sheep. Poor quality (high 1,8-cineole - low terpinen-4-ol) oil bearing tea tree (Melaleuca alternifolia) plantations have been established to the detriment of many a tea tree farmer. Analytical methods developed to check leaf quality at an early age indicated precursor sabinene constituents that convert to the active terpinen-4-ol both as the leaf matures or as the
Evaluation of fast enantioselective multidimensional gas chromatography methods for monoterpenic compounds: Authenticity control of Australian tea tree oil.
Wong, Yong Foo; West, Rachel N; Chin, Sung-Tong; Marriott, Philip J
This work demonstrates the potential of fast multiple heart-cut enantioselective multidimensional gas chromatography (GC-eGC) and enantioselective comprehensive two-dimensional gas chromatography (eGC×GC), to perform the stereoisomeric analysis of three key chiral monoterpenes (limonene, terpinen-4-ol and α-terpineol) present in tea tree oil (TTO). In GC-eGC, separation was conducted using a combination of mid-polar first dimension ((1)D) column and a chiral second dimension ((2)D) column, providing interference-free enantioresolution of the individual antipodes of each optically active component. A combination of (1)D chiral column and (2)D polar columns (ionic liquid and wax phases) were tested for the eGC×GC study. Quantification was proposed based on summation of two major modulated peaks for each antipode, displaying comparable results with those derived from GC-eGC. Fast chiral separations were achieved within 25min for GC-eGC and<20min for eGC×GC, while ensuring adequate interference-free enantiomer separation. The suitability of using these two enantioselective multidimensional approaches for the routine assessment of chiral monoterpenes in TTO was evaluated and discussed. Exact enantiomeric composition of chiral markers for authentic TTOs was proposed by analysing a representative number of pure TTOs sourced directly from plantations of known provenance in Australia. Consistent enantiomeric fractions of 61.6±1.5% (+):38.4±1.5% (-) for limonene, 61.7±1.6% (+):38.3±1.6% (-) for terpinen-4-ol and 79.6±1.4% (+):20.4±1.4% (-) for α-terpineol were obtained for the 57 authentic Australian TTOs. The results were compared (using principle component analysis) with commercial TTOs (declared as derived from Melaleuca alternifolia) obtained from different continents. Assessing these data to determine adulteration, or additives that affect the enantiomeric ratios, in commercially sourced TTOs is discussed. The proposed method offers distinct advantages over e
An abundant biological control agent does not provide a significant predator subsidy
Technology Transfer Automated Retrieval System (TEKTRAN)
Classical weed biological control agents, regardless of their effectiveness, may provide subsidies to predators and parasites. The chemically defended weevil Oxyops vitiosa Pascoe is a successful agent that was introduced to control the invasive tree Melaleuca quinquenervia. Two consecutive small ...
An Introduced Insect Biological Control Agent Preys on an Introduced Weed Biological Control Agent.
Technology Transfer Automated Retrieval System (TEKTRAN)
Biotic interference, especially by generalist predators, has been implicated in preventing establishment or limiting the impact of introduced weed biological control agents. Boreioglycaspis melaleucae Moore (Homoptera: Psyllidae) was released into Florida in 2002 as part of a classical biological c...
Fire Promotes Pollinator Visitation: Implications for Ameliorating Declines of Pollination Services
Van Nuland, Michael E.; Haag, Elliot N.; Bryant, Jessica A. M.; Read, Quentin D.; Klein, Robert N.; Douglas, Morgan J.; Gorman, Courtney E.; Greenwell, Trey D.; Busby, Mark W.; Collins, Jonathan; LeRoy, Joseph T.; Schuchmann, George; Schweitzer, Jennifer A.; Bailey, Joseph K.
Pollinators serve critical roles for the functioning of terrestrial ecosystems, and have an estimated annual value of over $150 billion for global agriculture. Mounting evidence from agricultural systems reveals that pollinators are declining in many regions of the world, and with a lack of information on whether pollinator communities in natural systems are following similar trends, identifying factors which support pollinator visitation and services are important for ameliorating the effects of the current global pollinator crisis. We investigated how fire affects resource structure and how that variation influences floral pollinator communities by comparing burn versus control treatments in a southeastern USA old-field system. We hypothesized and found a positive relationship between fire and plant density of a native forb, Verbesina alternifolia, as well as a significant difference in floral visitation of V. alternifolia between burn and control treatments. V. alternifolia density was 44% greater and floral visitation was 54% greater in burned treatments relative to control sites. When the density of V. alternifolia was experimentally reduced in the burn sites to equivalent densities observed in control sites, floral visitation in burned sites declined to rates found in control sites. Our results indicate that plant density is a proximal mechanism by which an imposed fire regime can indirectly impact floral visitation, suggesting its usefulness as a tool for management of pollination services. Although concerns surround the negative impacts of management, indirect positive effects may provide an important direction to explore for managing future ecological and conservation issues. Studies examining the interaction among resource concentration, plant apparency, and how fire affects the evolutionary consequences of altered patterns of floral visitation are overdue. PMID:24265787
Fire promotes pollinator visitation: implications for ameliorating declines of pollination services.
Van Nuland, Michael E; Haag, Elliot N; Bryant, Jessica A M; Read, Quentin D; Klein, Robert N; Douglas, Morgan J; Gorman, Courtney E; Greenwell, Trey D; Busby, Mark W; Collins, Jonathan; Leroy, Joseph T; Schuchmann, George; Schweitzer, Jennifer A; Bailey, Joseph K
Pollinators serve critical roles for the functioning of terrestrial ecosystems, and have an estimated annual value of over $150 billion for global agriculture. Mounting evidence from agricultural systems reveals that pollinators are declining in many regions of the world, and with a lack of information on whether pollinator communities in natural systems are following similar trends, identifying factors which support pollinator visitation and services are important for ameliorating the effects of the current global pollinator crisis. We investigated how fire affects resource structure and how that variation influences floral pollinator communities by comparing burn versus control treatments in a southeastern USA old-field system. We hypothesized and found a positive relationship between fire and plant density of a native forb, Verbesina alternifolia, as well as a significant difference in floral visitation of V. alternifolia between burn and control treatments. V. alternifolia density was 44% greater and floral visitation was 54% greater in burned treatments relative to control sites. When the density of V. alternifolia was experimentally reduced in the burn sites to equivalent densities observed in control sites, floral visitation in burned sites declined to rates found in control sites. Our results indicate that plant density is a proximal mechanism by which an imposed fire regime can indirectly impact floral visitation, suggesting its usefulness as a tool for management of pollination services. Although concerns surround the negative impacts of management, indirect positive effects may provide an important direction to explore for managing future ecological and conservation issues. Studies examining the interaction among resource concentration, plant apparency, and how fire affects the evolutionary consequences of altered patterns of floral visitation are overdue. PMID:24265787
Suppression of growth and reproduction of an exotic invasive tree by two introduced insects
Technology Transfer Automated Retrieval System (TEKTRAN)
The invasive tree Melaleuca quinquenervia experienced substantial declines in growth and reproduction in response primarily to chronic herbivory by the defoliating weevil Oxyops vitiosa. Herbivory was mediated on individual trees using regular applications of the insecticide acephate during a 2-yea...
The Use of an Invasive Species Habitat by a Small Folivorous Primate: Implications for Lemur Conservation in Madagascar.
Eppley, Timothy M; Donati, Giuseppe; Ramanamanjato, Jean-Baptiste; Randriatafika, Faly; Andriamandimbiarisoa, Laza N; Rabehevitra, David; Ravelomanantsoa, Robertin; Ganzhorn, Jörg U
The lemurs of Madagascar are among the most threatened mammalian taxa in the world, with habitat loss due to shifting cultivation and timber harvest heavily contributing to their precarious state. Deforestation often leads to fragmentation, resulting in mixed-habitat matrices throughout a landscape where disturbed areas are prone to invasion by exotic plants. Our study site, the Mandena littoral forest (southeast Madagascar), is a matrix of littoral forest, littoral swamp, and Melaleuca swamp habitats. Here, Melaleuca quinquenervia has invaded the wetland ecosystem, creating a mono-dominant habitat that currently provides the only potential habitat corridor between forest fragments. We sought to understand the role of this invasive Melaleuca swamp on the behavioral ecology of a threatened, small-bodied folivore, the southern bamboo lemur (Hapalemur meridionalis). We collected botanical and behavioral data on four groups of H. meridionalis between January and December 2013. Our results confirm Melaleuca swamp as an important part of their home range: while lemurs seasonally limited activities to certain habitats, all groups were capable of utilizing this invasive habitat for feeding and resting. Furthermore, the fact that Hapalemur use an invasive plant species as a dispersal corridor increases our knowledge of their ecological flexibility, and may be useful in the conservation management of remaining threatened populations. PMID:26536667
Acquired natural enemies of the weed biological control agent Oxyops vitiosa (Coleoptera: Curculionidae)
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian curculionid Oxyops vitiosa Pascoe was introduced into Florida during 1997 as a biological control agent of the invasive tree Melaleuca quinquenervia (Cav.) S.T. Blake. Populations of the weevil increased rapidly and became widely distributed throughout much of the invasive tree's adve...
Larval dispersal of the weed biological control agent Oxyops vitiosa (Coleoptera: Curculionidae)
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian weevil Oxyops vitiosa is a biological control agent of the exotic tree Melaleuca quinquenervia in Florida, USA. Evidence suggests that the last instar drops from the canopy to the forest floor to pupate in the soil or leaf litter. This dispersal method preempts weevil population persi...
Comparing native and exotic litter decomposition and nutrient dynamics.
Technology Transfer Automated Retrieval System (TEKTRAN)
Melaleuca quinquenervia is one of the most problematic invasive species in Florida Everglades' ecosystem. Treatment of these populations has been justified in part by hypothesized changes in the rate of organic matter decomposition and nutrient release from exotic litter. This study investigated t...
The Use of an Invasive Species Habitat by a Small Folivorous Primate: Implications for Lemur Conservation in Madagascar
Eppley, Timothy M.; Donati, Giuseppe; Ramanamanjato, Jean-Baptiste; Randriatafika, Faly; Andriamandimbiarisoa, Laza N.; Rabehevitra, David; Ravelomanantsoa, Robertin; Ganzhorn, Jörg U.
The lemurs of Madagascar are among the most threatened mammalian taxa in the world, with habitat loss due to shifting cultivation and timber harvest heavily contributing to their precarious state. Deforestation often leads to fragmentation, resulting in mixed-habitat matrices throughout a landscape where disturbed areas are prone to invasion by exotic plants. Our study site, the Mandena littoral forest (southeast Madagascar), is a matrix of littoral forest, littoral swamp, and Melaleuca swamp habitats. Here, Melaleuca quinquenervia has invaded the wetland ecosystem, creating a mono-dominant habitat that currently provides the only potential habitat corridor between forest fragments. We sought to understand the role of this invasive Melaleuca swamp on the behavioral ecology of a threatened, small-bodied folivore, the southern bamboo lemur (Hapalemur meridionalis). We collected botanical and behavioral data on four groups of H. meridionalis between January and December 2013. Our results confirm Melaleuca swamp as an important part of their home range: while lemurs seasonally limited activities to certain habitats, all groups were capable of utilizing this invasive habitat for feeding and resting. Furthermore, the fact that Hapalemur use an invasive plant species as a dispersal corridor increases our knowledge of their ecological flexibility, and may be useful in the conservation management of remaining threatened populations. PMID:26536667
Status of exotic woody species in big cypress national preserve. Technical report
Gunderson, L.H.
The current status of exotic woody plants in Big Cypress National Preserve is documented. A map of the distribution of principal pest species, Melaleuca quinquenervia, Schinus terebinthifolius, and Casuarina sp., is presented. Prognoses of population increases of these problem species are determined utilizing the current distributions and assessing environmental conditions. Some potential problem species are also identified.
Geographic range expansion of Oxyops vitiosa (Coleoptera: Curculionidae) to the Bahamian Archipelego
Technology Transfer Automated Retrieval System (TEKTRAN)
The Australian weevil Oxyops vitiosa is a specialized herbivore of Melaleuca quinquenervia and other closely related congeners. The weevil was intentionally introduced into Florida, USA in 1997 and was recently discovered on the Bahamian island of New Providence, some 300 km east, feeding on natural...
Response pattern of amino compounds in phloem and xylem of trees to soil drought depends on drought intensity and root symbiosis.
Liu, X-P; Gong, C-M; Fan, Y-Y; Eiblmeier, M; Zhao, Z; Han, G; Rennenberg, H
This study aimed to identify drought-mediated differences in amino nitrogen (N) composition and content of xylem and phloem in trees having different symbiotic N(2)-fixing bacteria. Under controlled water availability, 1-year-old seedlings of Robinia pseudoacacia (nodules with Rhizobium), Hippophae rhamnoides (symbiosis with Frankia) and Buddleja alternifolia (no such root symbiosis) were exposed to control, medium drought and severe drought, corresponding soil water content of 70-75%, 45-50% and 30-35% of field capacity, respectively. Composition and content of amino compounds in xylem sap and phloem exudates were analysed as a measure of N nutrition. Drought strongly reduced biomass accumulation in all species, but amino N content in xylem and phloem remained unaffected only in R. pseudoacacia. In H. rhamnoides and B. alternifolia, amino N in phloem remained constant, but increased in xylem of both species in response to drought. There were differences in composition of amino compounds in xylem and phloem of the three species in response to drought. Proline concentrations in long-distance transport pathways of all three species were very low, below the limit of detection in phloem of H. rhamnoides and in phloem and xylem of B. alternifolia. Apparently, drought-mediated changes in N composition were much more connected with species-specific changes in C:N ratios. Irrespective of soil water content, the two species with root symbioses did not show similar features for the different types of symbiosis, neither in N composition nor in N content. There was no immediate correlation between symbiotic N fixation and drought-mediated changes in amino N in the transport pathways. PMID:22845058
Repellency effect of forty-one essential oils against Aedes, Anopheles, and Culex mosquitoes.
Amer, Abdelkrim; Mehlhorn, Heinz
Since ancient times, plant products were used in various aspects. However, their use against pests decreased when chemical products became developed. Recently, concerns increased with respect to public health and environmental security requiring detection of natural products that may be used against insect pests. In this study, 41 plant extracts and 11 oil mixtures were evaluated against the yellow fever mosquito, Aedes aegypti (Linnaeus), the malaria vector, Anopheles stephensi (Liston), and the filariasis and encephalitis vector, Culex quinquefasciatus (Say) (Diptera: Culicidae) using the skin of human volunteers to find out the protection time and repellency. The five most effective oils were those of Litsea (Litsea cubeba), Cajeput (Melaleuca leucadendron), Niaouli (Melaleuca quinquenervia), Violet (Viola odorata), and Catnip (Nepeta cataria), which induced a protection time of 8 h at the maximum and a 100% repellency against all three species. This effect needs, however, a peculiar formulation to fix them on the human skin. PMID:16642384
In vitro antimicrobial evaluation of toothpastes with natural compounds
de Camargo Smolarek, Priscila; Esmerino, Luis Antonio; Chibinski, Ana Cláudia; Bortoluzzi, Marcelo Carlos; dos Santos, Elizabete Brasil; Kozlowski, Vitoldo Antonio
Objectives: This in vitro study evaluated the antimicrobial effects of commercial toothpastes containing natural compounds. Materials and Methods: The study groups were divided based on the natural compound present in the toothpaste composition: Sorbitol (I), tocopherol (II), mint (III), cinnamon/mint (IV), propolis/melaleuca (V), mint/açai (VI), mint/guarana (VII), propolis (VIII), negative control (IX), and the positive control (X). The antimicrobial properties of the toothpastes were tested using the disk diffusion method against oral pathogens: Streptococcus mutans, Pseudomonas aeruginosa, and Enterococcus faecalis. The resulting inhibition halos were measured in millimeters. Results: The data indicated that the bacteria responded differently to the toothpastes (P < 0.0001). The diameters of the inhibition halos against S. mutans were in decreasing order of efficacy: Propolis/melaleuca > mint/guarana > mint/açai > sorbitol > tocopherol > cinnamon/mint > propolis > mint (P < 0.001 vs. negative control). E. faecalis showed variable responses to the dentifrices in the following order of decreasing efficacy: Mint/guarana > propolis > sorbitol > mint/açai > tocopherol > cinnamon/mint > mint = propolis/melaleuca = negative control. The product with the highest antimicrobial activity was mint/guarana, which was significantly different than propolis/melaleuca, mint, cinnamon/mint, and tocopherol and negative control (P < 0.001). The statistical analysis indicated that propolis, sorbitol, and mint/açai did not show any differences compared to mint/guarana (P > 0.05) and positive control (P > 0.05). P. aeruginosa was resistant to all dental gels tested including positive control. Conclusion: The toothpastes with natural compounds have therapeutic potential and need more detailed searches for the correct clinic therapeutic application. The results from this study revealed differences in the antimicrobial activities of commercial toothpastes with natural compounds
Larvicidal activity of Myrtaceae essential oils and their components against Aedes aegypti, acute toxicity on Daphnia magna, and aqueous residue.
Park, Hye-Mi; Kim, Junheon; Chang, Kyu-Sik; Kim, Byung-Seok; Yang, Yu-Jung; Kim, Gil-Hah; Shin, Sang-Chul; Park, Il-Kwon
The larvicidal activity of 11 Myrtaceae essential oils and their constituents was evaluated against Aedes aegypti L. Of the 11, Melaleuca linariifolia Sm., Melaleuca dissitiflora F. Muell., Melaleuca quinquenervia (Cav.) S. T. Blake, and Eucalyptus globulus Labill oils at 0.1 mg/ml exhibited > or = 80% larval mortality. At this same concentration, the individual constituents tested, allyl isothiocyanate, alpha-terpinene, p-cymene, (+)-limonene, (-)-limonene, gamma-terpinene, and (E)-nerolidol, resulted in > or = 95% mortality. We also tested the acute toxicity of these four active oils earlier mentioned and their constituents against Daphnia magna Straus. M. linariifolia and allyl isothiocyanate was the most toxic to D. magna. Twodays after treatment, residues of M. dissitiflora, M. linariifolia, M. quinquenervia, and E. globulus oils in water were 55.4, 46.6, 32.4, and 14.8%, respectively. Less than 10% of allyl isothiocyanate, alpha-terpinene, p-cymene, (-)-limonene, (+)-limonene, and gamma-terpinene was detected in the water at 2 d after treatment. Our results indicated that oils and their constituents could easily volatilize in water within a few days after application, thus minimizing their effect on the aqueous ecosystem. Therefore, Myrtaceae essential oils and their constituents could be developed as control agents against mosquito larvae. PMID:21485381
Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants.
Subehan; Usia, Tepy; Iwata, Hiroshi; Kadota, Shigetoshi; Tezuka, Yasuhiro
Thirty samples of Indonesian medicinal plants were tested for their mechanism-based inhibition on cytochrome P450 3A4 (CYP3A4) and CYP2D6 via erythromycin N-demethylation and dextromethorphan O-demethylation activities in human liver microsomes. From screening with 0 and 20min preincubation at 0.5mg/ml of methanol extracts, five plants (Cinnamomum burmani bark, Foeniculum vulgare seed, Strychnos ligustrina wood, Tinospora crispa stem, and Zingiber cassumunar rhizome) showed more than 30% increase of CYP3A4 inhibition, while three (Alpinia galanga rhizome, Melaleuca leucadendron leaf, and Piper nigrum fruit) showed more than 30% increase of CYP2D6 inhibition. In these eight plants, Foeniculum vulgare seed, Cinnamomum burmani bark, and Strychnos ligustrina wood showed time-dependent inhibition on CYP3A4 and Piper nigrum fruit and Melaleuca leucadendron leaf on CYP2D6. Among these, four plants other than Melaleuca leucadendron revealed NADPH-dependent inhibition. Thus, Foeniculum vulgare, Cinnamomum burmani, and Strychnos ligustrina should contain mechanism-based inhibitors on CYP3A4 and Piper nigrum contain that on CYP2D6. PMID:16414224
Burning in Banksia Woodlands: How Does the Fire-Free Period Influence Reptile Communities?
Valentine, Leonie E.; Reaveley, Alice; Johnson, Brent; Fisher, Rebecca; Wilson, Barbara A.
Fire is an important management tool for both hazard reduction burning and maintenance of biodiversity. The impact of time since last fire on fauna is an important factor to understand as land managers often aim for prescribed burning regimes with specific fire-free intervals. However, our current understanding of the impact of time since last fire on fauna is largely unknown and likely dependent on vegetation type. We examined the responses of reptiles to fire age in banksia woodlands, and the interspersed melaleuca damplands among them, north of Perth, Western Australia, where the current prescribed burning regime is targeting a fire-free period of 8–12 years. The response of reptiles to fire was dependent on vegetation type. Reptiles were generally more abundant (e.g. Lerista elegans and Ctenophorus adelaidensis) and specious in banksia sites. Several species (e.g. Menetia greyii, Cryptoblepharus buchananii) preferred long unburnt melaleuca sites (>16 years since last fire, YSLF) compared to recently burnt sites (<12 YSLF). Several of the small elapids (e.g. the WA priority listed species Neelaps calonotus) were only detected in older-aged banksia sites (>16 YSLF). The terrestrial dragon C. adelaidensis and the skink Morethia obscura displayed a strong response to fire in banksia woodlands only. Highest abundances of the dragon were detected in the recently burnt (<7 YSLF) and long unburnt (>35 YSLF) banksia woodlands, while the skink was more abundant in older sites. Habitats from a range of fire ages are required to support the reptiles we detected, especially the longer unburnt (>16 YSLF) melaleuca habitat. Current burning prescriptions are reducing the availability of these older habitats. PMID:22496806
Australasian sequestrate fungi 18: Solioccasus polychromus gen. & sp. nov., a richly colored, tropical to subtropical, hypogeous fungus.
Trappe, James M; Castellano, Michael A; Halling, Roy E; Osmundson, Todd W; Binder, Manfred; Fechner, Nigel; Malajczuk, Nicholas
Solioccasus polychromus gen. & sp. nov., the most brightly colored hypogeous fungus known, is described from Papua New Guinea and tropical northern Australia south into subtropical forests along the Queensland coast and coastal mountains to near Brisbane. Phylogenetic analysis of molecular data places it as a sister genus to Bothia in the Boletineae, a clade of predominantly ectomycorrhizal boletes. Ectomycorrhizal trees, such as members of the Myrtaceae (Eucalyptus, Corymbia, Lophostemon, Melaleuca spp.) and Allocasuarina littoralis, were present usually in mixture or in some cases dominant, so we infer some or all of them to be among the ectomycorrhizal hosts of S. polychromus. PMID:23709482
A demonstration of wetland vegetation mapping in Florida from computer-processed satellite and aircraft multispectral scanner data
NASA Technical Reports Server (NTRS)
Butera, M. K. (Principal Investigator)
The author has identified the following significant results. Major vegetative classes identified by the remote sensing technique were cypress swamp, pine, wetland grasses, salt grass, mixed mangrove, black mangrove, Brazilian pepper. Australian pine and melaleuca were not satisfactorily classified from LANDSAT. Aircraft scanners provided better resolution resulting in a classification of finer surface detail. An edge effect, created by the integration of diverse spectral responses within boundary elements of digital data, affected the wetlands classification. Accuracy classification for aircraft was 68% and for LANDSAT was 74%.
Histological observation of Gelam (Melaleucacajuputi Powell) in different ecosystems of Terengganu
NASA Astrophysics Data System (ADS)
Mohamad, Masitah; Razak, Shamsul Bahri Abd; Salim, Jamilah Mohd.; Ismail, Salwani
A histological and anatomical comparative analysis of Gelam, Melaleuca cajuputi Powell was conducted to determine the adaptability Gelam (Melaleuca cajuputi Powell, Family = Myrtaceae) in two different micro-ecosystems of Terengganu. The sites sampling chosen were Jambu Bongkok Amenity Forest (Formerly known as Rantau Abang Amenity Forest), a large swamp forests and prominent flooding site in the District of Marang, Terengganu and Taman Penyelidikan Alam, Bukit Kor - a hard top soil area of Marang, Terengganu. The objective of this study is to compare the anatomy and histology features of gelam in these two areas. Results show that gelam from both ecosystems exhibits morphological differences and variations in some tissues (in leaf, petiole, bark, and root anatomy such as in type of epicuticular waxes, bark anatomy, leaf anatomy, vascular bundle, bark fibre pits, vessel, phloem, xylem, cortex, epidermal cells and mesophyll cells). This initial observation may suggest that gelam can adapt well in different micro-ecosystems of Terengganu. Its ability to response well toward Terengganu's different climates and coastal environmental changes could make gelam a viable tree for conservation and landscape program.
Protein kinase inhibitors in plants of the myrtaceae, proteaceae, and leguminosae.
Larkin, M; Brazier, J; Ternai, B; Polya, G M
Methanolic extracts of leaves, flowers, stems, bark, and other parts of representative plants of the Myrtaceae, specifically of the EUCALYPTUS, MELALEUCA, THRYPTOMENA, CALLISTOMEN, ACMENA, AND ANGOPHORA genera, variously contain high levels of inhibitors of plant Ca (2+)-dependent protein kinase (CDPK) and of Ca (2+)-calmodulin-dependent myosin light chain kinase (MLCK). In terms of the protein kinase inhibition unit (PKIU), defined as the amount in the standard protein kinase assays causing 50% inhibition of protein kinase activity, these inhibitor levels ranged from the non-detectable to 179,000 PKIU (gram fresh weight) (-1) [(g FW) (-1)] and there was no consistent pattern of inhibitor distribution. A variety of other plants tested had low or non-detectable levels of CDPK and MLCK inhibitors. Plants of the EUCALYPTUS, MELALEUCA, ANGOPHORA, and GREVILLEA genera contained inhibitors of the catalytic subunit of the cyclic AMP-dependent protein kinase (cAK), inhibitor levels ranging from 20,000 to 9,600,000 PKIU (g FW) (-1). In general, cAK inhibitor levels found in the Myrtaceae were mostly much higher than levels of CDPK and MLCK inhibitors and reversed phase HPLC of such plant extracts revealed a multiplicity of components associated with cAK inhibitory activity. These IN VITRO screening procedures enable rapid detection and quantitation of levels of bioactive plant defence compounds with medicinal potential. PMID:17230363
Description of a new genus and two new species of high frequency cicada from New Caledonia (Insecta: Hemiptera, Cicadoidea, Cicadidae).
Delorme, Quentin; Mille, Christian; Jourdan, Hervé
The new genus Murmurillana Delorme gen. nov., is described within the tribe Cicadettini Buckton, 1889, designating Murmurillana inaudibilis Delorme sp. nov., as the type species. Murmurillana inaudibilis Delorme sp. nov. and Murmurillana paenetacita Delorme sp. nov. are described from New Caledonia. They are respectively found in mid altitude dense Niaouli shrub (Melaleuca quinquenervia, Myrtaceae) vegetation, mixed with dense fern cover (Pteridium sp., Dennstaedtiaceae) on the Massif of Aoupinié (800 m) and on foothills of the Mont Panié (570 m). Male calling songs of the two new species are described from field recordings. These calling songs exhibit unusually high dominant frequencies. A key to the species of Murmurillana Delorme gen. nov., is also provided. PMID:27395606
Antibacterial Activity of Cinnamaldehyde and Estragole Extracted from Plant Essential Oils against Pseudomonas syringae pv. actinidiae Causing Bacterial Canker Disease in Kiwifruit
Song, Yu-Rim; Choi, Min-Seon; Choi, Geun-Won; Park, Il-Kwon; Oh, Chang-Sik
Pseudomonas syringae pv. actinidiae (Psa) causes bacterial canker disease in kiwifruit. Antibacterial activity of plant essential oils (PEOs) originating from 49 plant species were tested against Psa by a vapor diffusion and a liquid culture assays. The five PEOs from Pimenta racemosa, P. dioica, Melaleuca linariifolia, M. cajuputii, and Cinnamomum cassia efficiently inhibited Psa growth by either assays. Among their major components, estragole, eugenol, and methyl eugenol showed significant antibacterial activity by only the liquid culture assay, while cinnamaldehyde exhibited antibacterial activity by both assays. The minimum inhibitory concentrations (MICs) of estragole and cinnamaldehyde by the liquid culture assay were 1,250 and 2,500 ppm, respectively. The MIC of cinnamaldehyde by the vapor diffusion assay was 5,000 ppm. Based on the formation of clear zones or the decrease of optical density caused by these compounds, they might kill the bacterial cells and this feature might be useful for managing the bacterial canker disease in kiwifruit. PMID:27493612
[Peculicidal activity of plant essential oils and their based preparations].
Lopatina, Iu V; Eremina, O Iu
The peculicidal activity of eight plant essential oils in 75% isopropyl alcohol was in vitro investigated. Of them, the substances that were most active against lice were tea tree (Melaleuca), eucalyptus, neem, citronella (Cymbopogon nardus), and clove (Syzygium aromaticum) oils; KT50 was not more than 3 minutes on average; KT95 was 4 minutes. After evaporating the solvent, only five (tea tree, cassia, clove, anise (Anisum vulgare), and Japanese star anise (Illicium anisatum) oils) of the eight test botanical substances were active against lice. At the same time, KT50 and KT95 showed 1.5-5-fold increases. Citronella and anise oils had incomplete ovicidal activity. Since the lice were permethrin-resistant, the efficacy of preparations based on essential oils was much higher than permethrin. PMID:25296426
Primers for low-copy nuclear genes in Metrosideros and cross-amplification in Myrtaceae1
Pillon, Yohan; Johansen, Jennifer; Sakishima, Tomoko; Chamala, Srikar; Barbazuk, W. Brad; Stacy, Elizabeth A.
• Premise of the study: Primers were developed to amplify low-copy nuclear genes in Hawaiian Metrosideros (Myrtaceae). • Methods and Results: Data from a pooled 454 Titanium run of the partial transcriptomes of four Metrosideros taxa were used to identify the loci of interest. Ten exon-primed intron-crossing (EPIC) markers were amplified and sequenced directly with success in Metrosideros, as well as in a representative selection of Myrtaceae, including Syzygium, Psidium, and Melaleuca for most of the markers. The loci amplified ranged between 500 and 1100 bp, and up to 117 polymorphic sites were observed within an individual gene alignment. Two introns contained microsatellites in some of the species. • Conclusions: These novel primer pairs should be useful for phylogenetic analysis and population genetics of a broad range of Myrtaceae, particularly the diverse fleshy-fruited tribes Syzygieae and Myrteae. PMID:25309837
Antibacterial Activity of Cinnamaldehyde and Estragole Extracted from Plant Essential Oils against Pseudomonas syringae pv. actinidiae Causing Bacterial Canker Disease in Kiwifruit.
Song, Yu-Rim; Choi, Min-Seon; Choi, Geun-Won; Park, Il-Kwon; Oh, Chang-Sik
Pseudomonas syringae pv. actinidiae (Psa) causes bacterial canker disease in kiwifruit. Antibacterial activity of plant essential oils (PEOs) originating from 49 plant species were tested against Psa by a vapor diffusion and a liquid culture assays. The five PEOs from Pimenta racemosa, P. dioica, Melaleuca linariifolia, M. cajuputii, and Cinnamomum cassia efficiently inhibited Psa growth by either assays. Among their major components, estragole, eugenol, and methyl eugenol showed significant antibacterial activity by only the liquid culture assay, while cinnamaldehyde exhibited antibacterial activity by both assays. The minimum inhibitory concentrations (MICs) of estragole and cinnamaldehyde by the liquid culture assay were 1,250 and 2,500 ppm, respectively. The MIC of cinnamaldehyde by the vapor diffusion assay was 5,000 ppm. Based on the formation of clear zones or the decrease of optical density caused by these compounds, they might kill the bacterial cells and this feature might be useful for managing the bacterial canker disease in kiwifruit. PMID:27493612
The antioxidant effect of the Malaysian Gelam honey on pancreatic hamster cells cultured under hyperglycemic conditions.
Batumalaie, Kalaivani; Qvist, Rajes; Yusof, Kamaruddin Mohd; Ismail, Ikram Shah; Sekaran, Shamala Devi
Type 2 diabetes consists of progressive hyperglycemia, insulin resistance, and pancreatic β-cell failure which could result from glucose toxicity, inflammatory cytokines, and oxidative stress. In the present study, we investigate the effect of pretreatment with Gelam honey (Melaleuca spp.) and the individual flavonoid components chrysin, luteolin, and quercetin, on the production of reactive oxygen species (ROS), cell viability, lipid peroxidation, and insulin content in hamster pancreatic cells (HIT-T15 cells), cultured under normal and hyperglycemic conditions. Phenolic extracts from a local Malaysian species of Gelam honey (Melaleuca spp.) were prepared using the standard extraction methods. HIT-T15 cells were cultured in 5 % CO2 and then preincubated with Gelam honey extracts (20, 40, 60, and 80 μg/ml) as well as some of its flavonoid components chrysin, luteolin, and quercetin (20, 40, 60, and 80 μM), prior to stimulation by 20 and 50 mM of glucose. The antioxidative effects were measured in these cultured cells at different concentrations and time point by DCFH-DA assay. Pretreatment of cells with Gelam honey extract or the flavonoid components prior to culturing in 20 or 50 mM glucose showed a significant decrease in the production of ROS, glucose-induced lipid peroxidation, and a significant increase in insulin content and the viability of cells cultured under hyperglycemic condition. Our results show the in vitro antioxidative property of the Gelam honey and the flavonoids on the β-cells from hamsters and its cytoprotective effect against hyperglycemia. PMID:23584372
Contrasting impacts of localised versus catastrophic oil spills in coastal wetlands
Burns, K.A.; Codi, S.
A localised oil spill was observed on the wetland marshes bordering a tidal creek near Cairns, Queensland in January 1994. Pollution and conservation issues are of paramount public concern in this region which boarders World Heritage Areas of coral reefs and coastal habitats. Local residents observed oil being dumped from a truck which was contracted to of oil the surface of the roads in the contiguous sugar cane farm for dust control. During this incident several truckloads of mixed waste oil were dumped onto a short section of road and into the wetlands. The oil contaminated a band of marsh 15-30 m wide along approximately 200 m of road. Impacted marsh included Melaleuca forest on the high side of the road and intertidal mangroves on the seaward side. The Queensland Department of Environment (QDE) initiated an impact assessment and directed the trucking company to clean up impacted areas. The extent of damage to wetlands from oil spills is related to the amount and type of oil spilled and the sensitivity of the habitats oiled. QDE asked the Australian Institute of Marine Sciences to assist with their study on the fate of the oil in this localised spill. The initial levels of petroleum hydrocarbons in surface sediments reached 17% of the dry weight in heavily impacted areas. Thus levels were similar to those reached after the catastrophic oil spill in Panama. Clean up efforts and natural dissipation processes reduced sediment hydrocarbon loads to nonacutely toxic levels in only 1.5 years in the intertidal mangroves. High levels remain in the Melaleuca sediments. We used internal molecular markers to detail hydrocarbon dissipation vs degradation. This study provides a contrast between impacts of localised versus catastrophic oil spills in deep mud coastal habitats.
Fumigant activity of plant essential oils and components from garlic (Allium sativum) and clove bud (Eugenia caryophyllata) oils against the Japanese termite (Reticulitermes speratus Kolbe).
Park, Il-Kwon; Shin, Sang-Chul
Plant essential oils from 29 plant species were tested for their insecticidal activities against the Japanese termite, Reticulitermes speratus Kolbe, using a fumigation bioassay. Responses varied with plant material, exposure time, and concentration. Good insecticidal activity against the Japanese termite was achived with essential oils of Melaleuca dissitiflora, Melaleuca uncinata, Eucalyptus citriodora, Eucalyptus polybractea, Eucalyptus radiata, Eucalyptus dives, Eucalyptus globulus, Orixa japonica, Cinnamomum cassia, Allium cepa, Illicium verum, Evodia officinalis, Schizonepeta tenuifolia, Cacalia roborowskii, Juniperus chinensis var. horizontalis, Juniperus chinensis var. kaizuka, clove bud, and garlic applied at 7.6 microL/L of air. Over 90% mortality after 3 days was achieved with O. japonica essential oil at 3.5 microL/L of air. E. citriodora, C. cassia, A. cepa, I. verum, S. tenuifolia, C. roborowskii, clove bud, and garlic oils at 3.5 microL/L of air were highly toxic 1 day after treatment. At 2.0 microL/L of air concentration, essential oils of I. verum, C. roborowskik, S. tenuifolia, A. cepa, clove bud, and garlic gave 100% mortality within 2 days of treatment. Clove bud and garlic oils showed the most potent antitermitic activity among the plant essential oils. Garlic and clove bud oils produced 100% mortality at 0.5 microL/L of air, but this decreased to 42 and 67% after 3 days of treatment at 0.25 microL/L of air, respectively. Analysis by gas chromatography-mass spectrometry led to the identification of three major compounds from garlic oil and two from clove bud oils. These five compounds from two essential oils were tested individually for their insecticidal activities against Japanese termites. Responses varied with compound and dose. Diallyl trisulfide was the most toxic, followed by diallyl disulfide, eugenol, diallyl sulfide, and beta-caryophyllene. The essential oils described herein merit further study as potential fumigants for termite
Eucalyptus Pollen Allergy and Asthma in Children: A Cross-Sectional Study in South-East Queensland, Australia
Gibbs, Jane E. M.
Objectives To investigate Eucalyptus (gum tree) pollen allergy in children in relation to geography, particularly vegetation, and its relationship to asthma. Methods Males (n = 180) and females (n = 200) aged 9 to 14 participated. Some were healthy (asymptomatic), some had asthma, and some had other symptoms associated with atopy. School students were from three urban coastal schools and one school from a nearby semi-rural elevated area (range) near Brisbane, Australia. Coastal and range locations featured different distributions of Myrtaceae family vegetation (including Eucalyptus, Melaleuca, Leptospermum species). Skin prick test (SPT) responses to 15 commercial allergens were compared. As well, responses from coast versus range groups, and 'asthma' (n = 97) versus 'healthy' status (n = 107) groups, were compared. Results SPT responses (≥3mm wheal diameter) indicate that children with asthma are 31.1 times more likely to be allergic to Eucalyptus pollen extract (OR: 31.1; 95%CI 4.1- 235.7) compared to healthy children. Dust mite (p = .018), Eucalyptus (p = .046) and cockroach (p = .047) allergen SPT responses (wheals ≥3mm) were significantly greater in participants located on the coast versus range as determined by Fisher's Exact Test (α .05). For each location, percentage of positive responses (wheals ≥3mm) was greatest for 'dust mite' (30.9%-46%), 'cockroach' (18.1% -35%) and 'Bermuda grass' (10.6%-19.4%). Conclusions The results support the hypothesis that proximity to Myrtaceae vegetation is related to positive SPT response and that Eucalyptus is an important allergen for children with asthma. Substantial response to olive allergen, in the absence of olive trees, suggests that the response may be driven by substances in other plants, perhaps Melaleuca quinquenervia, which abounds in coastal areas. Implications Response to Eucalyptus allergen indicates that changes in gardening practice in schools and public areas may be
Gelam Honey Scavenges Peroxynitrite During the Immune Response
Kassim, Mustafa; Mansor, Marzida; Suhaimi, Anwar; Ong, Gracie; Yusoff, Kamaruddin Mohd
Monocytes and macrophages are part of the first-line defense against bacterial, fungal, and viral infections during host immune responses; they express high levels of proinflammatory cytokines and cytotoxic molecules, including nitric oxide, reactive oxygen species, and their reaction product peroxynitrite. Peroxynitrite is a short-lived oxidant and a potent inducer of cell death. Honey, in addition to its well-known sweetening properties, is a natural antioxidant that has been used since ancient times in traditional medicine. We examined the ability of Gelam honey, derived from the Gelam tree (Melaleuca spp.), to scavenge peroxynitrite during immune responses mounted in the murine macrophage cell line RAW 264.7 when stimulated with lipopolysaccharide/interferon-γ (LPS/IFN-γ) and in LPS-treated rats. Gelam honey significantly improved the viability of LPS/IFN-γ-treated RAW 264.7 cells and inhibited nitric oxide production—similar to the effects observed with an inhibitor of inducible nitric oxide synthase (1400W). Furthermore, honey, but not 1400W, inhibited peroxynitrite production from the synthetic substrate 3-morpholinosydnonimine (SIN-1) and prevented the peroxynitrite-mediated conversion of dihydrorhodamine 123 to its fluorescent oxidation product rhodamine 123. Honey inhibited peroxynitrite synthesis in LPS-treated rats. Thus, honey may attenuate inflammatory responses that lead to cell damage and death, suggesting its therapeutic uses for several inflammatory disorders. PMID:23109904
Crassulacean acid metabolism (CAM) in an epiphytic ant-plant, Myrmecodia beccarii Hook.f. (Rubiaceae).
Tsen, Edward W J; Holtum, Joseph A M
This study demonstrates unequivocally the presence of crassulacean acid metabolism (CAM) in a species of the Rubiaceae, the fourth largest angiosperm plant family. The tropical Australian endemic epiphytic ant-plant, Myrmecodia beccarii Hook.f., exhibits net CO(2) uptake in the dark and a concomitant accumulation of titratable acidity in plants in the field and in cultivation. Plants growing near Cardwell, in a north Queensland coastal seasonally dry forest of Melaleuca viridiflora Sol. ex Gaertn., accumulated ~50 % of their 24 h carbon gain in the dark during the warm wet season. During the transition from the wet season to the dry season, 24 h carbon gain was reduced whilst the proportion of carbon accumulated during the dark increased. By mid dry season many plants exhibited zero net carbon uptake over 24 h, but CO(2) uptake in the dark was observed in some plants following localised rainfall. In a shade-house experiment, droughted plants in which CO(2) uptake in the light was absent and dark CO(2) uptake was reduced, were able to return to relatively high rates of CO(2) uptake in the light and dark within 12 h of rewatering. PMID:22442054
Antioxidant capacities and total phenolic contents of 56 wild fruits from South China.
Fu, Li; Xu, Bo-Tao; Xu, Xiang-Rong; Qin, Xin-Sheng; Gan, Ren-You; Li, Hua-Bin
In order to identify wild fruits possessing high nutraceutical potential, the antioxidant activities of 56 wild fruits from South China were systematically evaluated. The fat-soluble components were extracted with tetrahydrofuran, and the water-soluble ones were extracted with a 50:3.7:46.3 (v/v) methanol-acetic acid-water mixture. The antioxidant capacities of the extracts were evaluated using the ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) assays, and their total phenolic contents were measured by the Folin-Ciocalteu method. Most of these wild fruits were analyzed for the first time for their antioxidant activities. Generally, these fruits had high antioxidant capacities and total phenolic contents. A significant correlation between the FRAP value and the TEAC value suggested that antioxidant components in these wild fruits were capable of reducing oxidants and scavenging free radicals. A high correlation between antioxidant capacity and total phenolic content indicated that phenolic compounds could be the main contributors to the measured antioxidant activity. The results showed that fruits of Eucalyptus robusta, Eurya nitida, Melastoma sanguineum, Melaleuca leucadendron, Lagerstroemia indica, Caryota mitis, Lagerstroemia speciosa and Gordonia axillaris possessed the highest antioxidant capacities and total phenolic contents among those tested, and could be potential rich sources of natural antioxidants and functional foods. The results obtained are very helpful for the full utilization of these wild fruits. PMID:21116229
Identity and specificity of the fungi forming mycorrhizas with the rare mycoheterotrophic orchid Rhizanthella gardneri.
Bougoure, Jeremy; Ludwig, Martha; Brundrett, Mark; Grierson, Pauline
Fully subterranean Rhizanthella gardneri (Orchidaceae) is obligately mycoheterotrophic meaning it is nutritionally dependent on the fungus it forms mycorrhizas with. Furthermore, R. gardneri purportedly participates in a nutrient sharing tripartite relationship where its mycorrhizal fungus simultaneously forms ectomycorrhizas with species of Melaleuca uncinata s.l. Although the mycorrhizal fungus of R. gardneri has been morphologically identified as Thanatephorus gardneri (from a single isolate), this identification has been recently questioned. We sought to clarify the identification of the mycorrhizal fungus of R. gardneri, using molecular methods, and to identify how specific its mycorrhizal relationship is. Fungal isolates taken from all sites where R. gardneri is known to occur shared almost identical ribosomal DNA (rDNA) sequences. The fungal isolate rDNA most closely matched that of other Ceratobasidiales species, particularly within the Ceratobasidium genus. However, interpretation of results was difficult as we found two distinct ITS sequences within all mycorrhizal fungal isolates of R. gardneri that we assessed. All mycorrhizal fungal isolates of R. gardneri readily formed ectomycorrhizas with a range of M. uncinata s.l. species. Consequently, it is likely that R. gardneri can form a nutrient sharing tripartite relationship where R. gardneri is connected to autotrophic M. uncinata s.l. by a common mycorrhizal fungus. These findings have implications for better understanding R. gardneri distribution, evolution and the ecological significance of its mycorrhizal fungus, particularly in relation to nutrient acquisition. PMID:19619652
Activity profiles and hook-tool use of New Caledonian crows recorded by bird-borne video cameras.
Troscianko, Jolyon; Rutz, Christian
New Caledonian crows are renowned for their unusually sophisticated tool behaviour. Despite decades of fieldwork, however, very little is known about how they make and use their foraging tools in the wild, which is largely owing to the difficulties in observing these shy forest birds. To obtain first estimates of activity budgets, as well as close-up observations of tool-assisted foraging, we equipped 19 wild crows with self-developed miniature video cameras, yielding more than 10 h of analysable video footage for 10 subjects. While only four crows used tools during recording sessions, they did so extensively: across all 10 birds, we conservatively estimate that tool-related behaviour occurred in 3% of total observation time, and accounted for 19% of all foraging behaviour. Our video-loggers provided first footage of crows manufacturing, and using, one of their most complex tool types--hooked stick tools--under completely natural foraging conditions. We recorded manufacture from live branches of paperbark (Melaleuca sp.) and another tree species (thought to be Acacia spirorbis), and deployment of tools in a range of contexts, including on the forest floor. Taken together, our video recordings reveal an 'expanded' foraging niche for hooked stick tools, and highlight more generally how crows routinely switch between tool- and bill-assisted foraging. PMID:26701755
Synergistic repellent and irritant effect of combined essential oils on Aedes aegypti (L.) mosquitoes.
Noosidum, Atirach; Chareonviriyaphap, Theeraphap; Chandrapatya, Angsumarn
This study was designed to compare the behavioral responses of Aedes aegypti to a single essential oil and to a mixture of two or three essential oils using an excito-repellency test chamber. Mixtures were prepared from essential oils extracted from Litsea cubeba (LC), Litsea salicifolia (LS), and Melaleuca leucadendron (ML). In general, the mixture of essential oils produced a much stronger escape response by Ae. aegypti, regardless of the test conditions. No significant difference in escape responses was seen when the mixture of oils was compared with a standard commercial product containing DEET. Greater contact irritancy was seen from mixed oils of LC and LS than with other mixed oils. Mixtures of LC and LS at 0.075% showed the highest synergistic action (65.5% escaped) compared to that with unmixed oil alone at the same concentration (LC/20% and LS=32.2%). In addition, mixtures of LC and LS at 0.075% demonstrated the highest non-contact repellency (62.7%) and showed a greater effect than the use of LC (20%) or LS (20.3%) alone. We conclude that mixtures of two essential oils show potential as active ingredients for mosquito repellents. PMID:25424258
Interactions of Metarhizium anisoplae and tree-based mulches in repellence and mycoses against Coptotermes formosanus (Isoptera: Rhinotermitidae).
Sun, Jian-Zhong; Fuxa, James R; Richter, Arthur; Ring, Dennis
The use of mulch in urban landscapes has increased in the United States for the past decade. Tree-based organic mulches can supply Coptotermes formosanus Shiraki with food, moisture, and shelter. The current research contributes to mulch management technology in termite control. A choice test arena was designed to determine the repellence and mortality caused by commercial mulches treated with different concentrations of the fungus Metarhizium anisopliae (Metschnikoff) against C. formosanus. Each of six tree-based mulches (pine bark, pine straw, bald cypress, eucalyptus, water oak, and melaleuca) was coated with six conidial concentrations ranging from 1 x 10(3) to 1 x 10(8) conidia/ml. The foragers of C. formosanus were repelled significantly by the fungal-treated mulch substrates; the proportion of termites on fungal-treated mulch was usually <20% during the 28-d test. By day 28, >99% of the termites were killed in test arenas containing a chamber with mulch treated with 10(7) or 10(8) conidia/ml. M. anisopliae significantly reduced mulch consumption by 34-71%. Mulch consumption by the termites was negatively correlated with fungal concentration, and the type of mulch also affected consumption. The differences in termite foraging activities, mortality, and food consumption among mulches were usually confounded by differences in fungal concentrations of M. anisopliae. The results indicate that repellence and virulence of M. anisopliae conidia should significantly reduce the suitability of these six mulches as a habitat for C. formosanus. PMID:18559182
Identification of Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum from honey stomach of honeybee
Tajabadi, Naser; Mardan, Makhdzir; Saari, Nazamid; Mustafa, Shuhaimi; Bahreini, Rasoul; Manap, Mohd Yazid Abdul
This study aimed to isolate and identify Lactobacillus in the honey stomach of honeybee Apis dorsata. Samples of honeybee were collected from A. dorsata colonies in different bee trees and Lactobacillus bacteria isolated from honey stomachs. Ninety two isolates were Gram-stained and tested for catalase reaction. By using bacterial universal primers, the 16S rDNA gene from DNA of bacterial colonies amplified with polymerase chain reaction (PCR). Forty-nine bacterial 16S rDNA gene were sequenced and entrusted in GenBank. Phylogenetic analysis showed they were different phylotypes of Lactobacillus. Two of them were most closely relevant to the previously described species Lactobacillus plantarum. Other two phylotypes were identified to be closely related to Lactobacillus pentosus. However, only one phylotype was found to be distantly linked to the Lactobacillus fermentum. The outcomes of the present study indicated that L. plantarum, L. pentosus, and L. fermentum were the dominant lactobacilli in the honey stomach of honeybee A. dorsata collected during the dry season from Malaysia forest area - specifically "Melaleuca in Terengganu". PMID:24516438
Nutritional characteristics of the leaves of native plants growing in adverse soils of humid tropical lowlands.
Osaki, Mitsuru; Watanabe, Toshihiro; Ishizawa, Tetsuya; Nilnond, Chairatna; Nuyim, Tanit; Shinano, Takuro; Urayama, Masaru; Tuah, Sehat Jaya
Acid sulfate, peat, sandy podzolic, and saline soils are widely distributed in the lowlands of Thailand and Malaysia. The nutrient concentrations in the leaves of plants grown in these type of soils were studied with the aim of developing a nutritional strategy for adapting to such problem soils. In sago and oil palms that were well-adapted to peat soil, the N, P, and K concentrations were the same in the mature leaves, while the Ca, Mg, Na, and Fe concentrations were higher in the mature leaves of the oil palm than of the sago palm. Melastoma malabathricum and Melaleuca cajuputi plants that were well-adapted to low pH soils, peat. and acid sulfate soils were also studied. It was observed that a high amount of Al accumulated in the M. marabathricum leaves, while Al did not accumulate in M. cajuputi leaves. M. cajuputi plants accumulated large amounts of Na in their leaves or stems regardless of the exchangeable Na concentration in the soil, while M. malabathricum that was growing in saline-affected soils excluded Na. Positive relationships between macronutrients were recognized between P and N, between K and N, and between P and K. Al showed antagonistic relationships with P, K, Ca, Mg, Fe, Zn, Cu, and Na. Na also showed antagonistic relationships with P, K, Zn, Mn, Cu, and Al. Fe showed weak antagonistic relationships with Zn, Mn, Cu, and Al. PMID:12906350
Antimicrobial effects of selected plant essential oils on the growth of a Pseudomonas putida strain isolated from meat.
Oussalah, Mounia; Caillet, Stéphane; Saucier, Linda; Lacroix, Monique
The inhibitory effect of 60 different essential oils was evaluated on a Pseudomonas putida strain of meat origin, associated with meat spoilage. Essential oils were tested at concentrations from 0.003 to 0.8% (wt/vol) to determine minimum inhibitory and maximal tolerated concentrations (MIC and MTC, respectively) using an agar medium culture. Of the 60 samples tested, Corydothymus capitatus essential oil was the most active showing a MIC of 0.025% and a MTC of 0.06%. Seven essential oils (Cinnamomum cassia, Origanum compactum, Origanum heracleoticum, Satureja hortensis, Satureja montana, Thymus vulgaris carvacroliferum, Thymus vulgaris thymoliferum) have shown a strong antimicrobial activity against P. putida with a MIC of 0.05% and a MTC ranging from 0.013% to 0.025%. Ten other oils (Cinnamomum verum (leaf and bark), Eugenia caryophyllus, Cymbopogon martinii var. motia, Cymbopogon nardus, Melaleuca linariifolia, Origanum majorana, Pimenta dioica, Thymus satureoides, Thymus serpyllum) showed a high antimicrobial activity showing a MIC ranging from 0.1% to 0.4%, while the remaining were less active showing a MIC⩾0.8%. PMID:22062294
Drivers of Coastal Shoreline Change: Case Study of Hon Dat Coast, Kien Giang, Vietnam
NASA Astrophysics Data System (ADS)
Nguyen, Hai-Hoa; McAlpine, Clive; Pullar, David; Leisz, Stephen Joseph; Galina, Gramotnev
Coastal shorelines are naturally dynamic, shifting in response to coastal geomorphological processes. Globally, land use change associated with coastal urban development and growing human population pressures is accelerating coastal shoreline change. In southern Vietnam, coastal erosion currently is posing considerable risks to shoreline land use and coastal inhabitants. The aim of this paper is to quantify historical shoreline changes along the Hon Dat coast between 1995 and 2009, and to document the relationships between coastal mangrove composition, width and density, and rates of shoreline change. The generalized linear mixed-effects models were used to quantify the major biophysical and land-use factors influencing shoreline change rates. Most significant drivers of the rates of change are cutting of mangroves, the dominant mangrove genus, changes in adjacent shoreline land use, changes of shoreline land cover, and width of fringing mangroves. We suggest that a possible and inexpensive strategy for robust mangrove shoreline defense is direct mangrove planting to promote mangrove density with the presence of breakwater structures. In the shorter term, construction of coastal barriers such as fence-structured melaleuca poles in combination with mangrove restoration schemes could help retain coastal sediments and increase the elevation of the accretion zone, thereby helping to stabilize eroding fringe shorelines. It also is recommended that implementation of a system of payments for mangrove ecosystem services and the stronger regulation of mangrove cutting and unsustainable land-use change to strengthen the effectiveness of mangrove conservation programs and coastal land-use management.
An investigation into the effectiveness of sand media amended with biochar to remove BOD5, suspended solids and coliforms using wetland mesocosms.
de Rozari, P; Greenway, M; El Hanandeh, A
Constructed wetland ecotechnologies (CWEs) are a promising solution to effectively treat domestic wastewater in developing countries at low cost. This paper reports the findings of the effectiveness of sand media amended with woody biochar and two plants species (Melaleuca quinquenervia and Cymbopogon citratus) in removing biological oxygen demand (BOD5), suspended solids and coliforms. The experimental design consisted of 21 vertical flow (VF) mesocosms. There were seven media treatments using sand amended with varying proportions of biochar. During the first 8 months, the mesocosms were loaded with secondary clarified wastewater (SCW) then septage. The influent had a 4-day hydraulic retention time. Samples were monitored for BOD5, total suspended solids (TSS), total volatile solids (TVS), total coliforms and faecal coliforms. In the first 8 months, there were no significant performance differences between media treatments in the outflow concentrations of BOD5, TSS and TVS. The significant differences occurred during the last 3 months; using septage with biochar additions performed better than pure sand. For coliforms, the significant differences occurred after 6 months. In conclusion, the addition of biochar was not effective for SCW. The VF mesocosms system proved to be more effective in removing BOD5, TSS, TVS and coliforms when septage was loaded into the media. PMID:26442496
Chemical detoxification vs mechanical removal of host plant toxins in Eucalyptus feeding sawfly larvae (Hymenoptera: Pergidae).
Schmidt, S; McKinnon, A E; Moore, C J; Walter, G H
The essential oils that characterize the eucalypts and related Myrtaceae pose a challenge for herbivores. Phytophagous insects that feed on oil-rich Myrtaceae have developed specific mechanisms to deal with these oils, some of which are notoriously toxic (e.g. 1,8-cineole). Some of the eight Australian subfamilies in the sawfly family Pergidae are associated exclusively with Eucalyptus and Melaleuca species that often have high concentrations of essential oils. Unexpectedly, the Perginae and Pterygophorinae use different mechanisms to deal with the same toxic components in their respective host plants. Larvae of the Perginae have the inner surface of their mandibles equipped with soft brush-like structures that are unique among phytophagous insects in general. The proposed role of these ancillary mandibular structures in separating leaf oils from nutritive plant matter could be confirmed in experiments with larvae of two pergine species. The oil sequestration is, however, incomplete and chemical gut content analyses by gas-chromatography (GC) revealed that 1,8-cineole does enter the midgut and is metabolised to hydroxycineole. Although the related Pterygophorinae also feed mainly on oil-rich Myrtaceae, they do not sequester the oil and lack morphological structures on their mandibles. Chemical analysis of the gut content of two pterygophorine species showed that they rely solely on chemical detoxification of the relevant plant compounds, with GC demonstrating that the 1,8-cineole is removed far more rapidly and completely than in the pergine species. PMID:20655314
Isolation and identification of the toxic peptides from Lophyrotoma zonalis (Pergidae) sawfly larvae.
Oelrichs, P B; MacLeod, J K; Seawright, A A; Grace, P B
The broad-leaved paper bark tree Melaleuca quinquenervia (Cav) (Myrtaceae) was introduced into Florida (USA) early in this century it has proliferated to such an extent that urgent measures are now required to control it. The sawfly Lophyrotoma zonalis (Pergidae) has been introduced as a possible biological control agent due to its ability to defoliate M. quinquenervia. Because toxic D-amino acid- containing peptides have been isolated from some sawfly species, L. zonalis larvae were processed using the previously reported method for the recovery of these compounds. The toxins lophyrotomin (as the free C-terminal acid) and a mixture of pergidin and Val (4)-pergidin were isolated at 0.36 and 0.43% yield of the dried larvae, respectively. Both compounds when dosed intraperitoneally to C57/Bl6 male mice were hepatotoxic with lowest lethal doses of 8 and 32 mg/kg, respectively. The pathology of the liver was different for each compound, with the lophyrotomin free acid causing a periportal haemorrhagic necrosis and the pergidin causing a periacinar coagulative necrosis. PMID:11600157
Efficacy of commercially available products against Gyrodactylus turnbulli infections on guppies Poecilia reticulata.
Schelkle, Bettina; Snellgrove, Donna; Jones, Lewis L; Cable, Jo
The demand for ornamental fish has led to a steep rise in aquaculture for the hobbyist trade, promoting the emergence, persistence and spread of various infectious diseases. Complete control of disease outbreaks with antibiotics and chemical-based medicines is rare, but plant compounds may herald potential alternatives effective against a range of pathogens. Melafix® and Pimafix® are formulated with the essential oils cajuput (Melaleuca cajuputi) and West Indian bay (Pimenta racemosa) and are marketed against bacterial and fungal infections, respectively. Previous experiments showed high efficacy of emulsified cajuput oil against gyrodactylids; the current study tested Melafix® and Pimafix® and their individual compounds against Gyrodactylus turnbulli infecting the guppies Poecilia reticulata. In particular, a combination treatment of Melafix® and Pimafix® was highly effective at reducing in vitro survival of parasites from 15 to 2 h and eradicating 95% of gyrodactylids in vivo. The unexpected high efficacy of this combination treatment is likely explained by the high content of terpenes and phenol propanoids in the cajuput and West Indian bay oils, as well as the anti-helminthic properties of the emulsifier Crovol PK 70. Hence, Melafix® and Pimafix® effectively reduce gyrodactylid burdens on fish, increasing the chances of efficient disease control in ornamental fish. PMID:26203884
Role of antifungal agents in the treatment of seborrheic dermatitis.
Gupta, Aditya K; Nicol, Karyn; Batra, Roma
Seborrheic dermatitis is a superficial fungal disease of the skin, occurring in areas rich in sebaceous glands. It is thought that an association exists between Malassezia yeasts and seborrheic dermatitis. This may, in part, be due to an abnormal or inflammatory immune response to these yeasts. The azoles represent the largest class of antifungals used in the treatment of this disease to date. In addition to their antifungal properties, some azoles, including bifonazole, itraconazole, and ketoconazole, have demonstrated anti-inflammatory activity, which may be beneficial in alleviating symptoms. Other topical antifungal agents, such as the allylamines (terbinafine), benzylamines (butenafine), hydroxypyridones (ciclopirox), and immunomodulators (pimecrolimus and tacrolimus), have also been effective. In addition, recent studies have revealed that tea tree oil (Melaleuca oil), honey, and cinnamic acid have antifungal activity against Malassezia species, which may be of benefit in the treatment of seborrheic dermatitis. In cases where seborrheic dermatitis is widespread, the use of an oral therapy, such as ketoconazole, itraconazole, and terbinafine, may be preferred. Essentially, antifungal therapy reduces the number of yeasts on the skin, leading to an improvement in seborrheic dermatitis. With a wide availability of preparations, including creams, shampoos, and oral formulations, antifungal agents are safe and effective in the treatment of seborrheic dermatitis. PMID:15663338
Activity profiles and hook-tool use of New Caledonian crows recorded by bird-borne video cameras
Troscianko, Jolyon; Rutz, Christian
New Caledonian crows are renowned for their unusually sophisticated tool behaviour. Despite decades of fieldwork, however, very little is known about how they make and use their foraging tools in the wild, which is largely owing to the difficulties in observing these shy forest birds. To obtain first estimates of activity budgets, as well as close-up observations of tool-assisted foraging, we equipped 19 wild crows with self-developed miniature video cameras, yielding more than 10 h of analysable video footage for 10 subjects. While only four crows used tools during recording sessions, they did so extensively: across all 10 birds, we conservatively estimate that tool-related behaviour occurred in 3% of total observation time, and accounted for 19% of all foraging behaviour. Our video-loggers provided first footage of crows manufacturing, and using, one of their most complex tool types—hooked stick tools—under completely natural foraging conditions. We recorded manufacture from live branches of paperbark (Melaleuca sp.) and another tree species (thought to be Acacia spirorbis), and deployment of tools in a range of contexts, including on the forest floor. Taken together, our video recordings reveal an 'expanded' foraging niche for hooked stick tools, and highlight more generally how crows routinely switch between tool- and bill-assisted foraging. PMID:26701755
E. coli removal in laboratory scale stormwater biofilters: Influence of vegetation and submerged zone
NASA Astrophysics Data System (ADS)
Chandrasena, G. I.; Pham, T.; Payne, E. G.; Deletic, A.; McCarthy, D. T.
Biofilters, also known as bioretention areas or raingardens, are an effective treatment option for the removal of various pollutants from stormwater. However, they show variable treatment efficiency for the removal of indicator bacteria, and the operational and design factors which impact this variability are largely unknown. This study uses a laboratory scale column set-up to explore how Escherichia coli (the chosen indicator organism) removal in the stormwater biofilters is impacted by: plant presence and species type, the presence of a submerged zone (SZ), and operational conditions (duration of dry periods and changes over the initial stages of the system's life-span). Vegetation selection was found to be important for E. coli removal and the highly performing plant species were associated with lower infiltration rates. Based on the current results, a biofilter planted with Leptospermum continentale, Melaleuca incana or Palmetto buffalo and comprising a SZ can be recommended for improved E. coli removal. Inclusion of SZ was found to generally enhance the removal performance; which may be explained by the contribution of microbial processes that are happening within the SZ (such as predation/competition and natural die-off). Results also suggest that the E. coli removal performance is reduced after a significant dry period, while the overall removal performance improves over time as systems mature.
Mapping wetland species and the impact of oil from the Deep Horizon using the Airborne/Visible Imaging Spectrometer and Multiple Endmember Spectral Mixture Analysis
NASA Astrophysics Data System (ADS)
Roberts, D. A.; Beland, M.; Kokaly, R. F.; Couvillion, B.; Ustin, S.; Peterson, S.
Between April 20, 2010 and July 15, 2010 an estimated 4.4 million barrels of oil leaked from the Maconda well, making the Deep Horizon oil spill the largest in US history. In response to a need to determine the distribution of wetland plant species and quantify their condition prior to, during and after oil reached the shore, the Airborne/Visible Infrared Imaging Spectrometer (AVIRIS) was deployed multiple times in the gulf on high altitude and low altitude airborne platforms. Significant research questions included 1) What is the distribution of key wetland species in the impacted area?; 2) which areas were impacted by oil, when and to what extent?; 3) how much oil must be present to be detected in various cover types? and 4) which wetland species are more sensitive to oil? In an effort to answer some of these questions, we applied Multiple Endmember Spectral Mixture Analysis (MESMA) to AVIRIS data acquired prior to significant impacts in May, 2010 and after oil had reached wetlands in late summer and fall, 2010. Reference polygons for species dominants were located on the images and used to build a spectral library for all dominant wetland species and surface types. This spectral library was augmented by field spectra, acquired using a contact probe for senesced plants materials and beach sands. Spectra of heavily oiled surfaces were identified using the Hydrocarbon Index to identify potential oil endmembers and the Cellulose Absorption Index to discriminate oil from Non-photosynthetic Vegetation (NPV). Wetland species and cover fractions for Green Vegetation (GV), NPV, soils/beaches, oil and water were mapped using MESMA applied to images acquired in the Birds Foot Delta, Chandeleur Islands and Barataria Bay. Species maps, showing dominant species such as Phragmites australis, Spartina alternifolia and S. patens proved to be accurate. OIl was mapped along coastal areas of Barataria Bay, expressed as high oil fractions. However, significant confusion was also
Fiddling with the proof: the Magpie Fiddler Ray is a colour pattern variant of the common Southern Fiddler Ray (Rhinobatidae: Trygonorrhina).
Donnellan, Stephen C; Foster, Ralph; Junge, Claudia; Huveneers, Charlie; Rogers, Paul; Kilian, Andrzej; Bertozzi, Terry
The Magpie Fiddler ray, Trygonorrhina melaleuca Scott 1954, is presently South Australia's (SA) rarest fish, represented by only three museum specimens collected near Adelaide over the past 60 years and listed as Endangered in the IUCN Red List of Threatened Species. However, there is some doubt as to whether the Magpie Fiddler Ray is a different species from the widespread and common Southern Fiddler Ray, Trygonorrhina dumerilii (Castelnau 1873), resulting in two very contrasting scenarios for marine conservation. If the Magpie Fiddler Ray is a black and white patterned variant of the Southern Fiddler Ray then it will be removed from the Red List and appear as a synonym of T. dumerilii. Conversely, if it proves to be a different species then it remains SA's rarest fish species and highly data deficient. We analysed mtDNA and the largest ever nuclear gene dataset (>4,000 loci) applied to chondrichthyan species level systematics from the most recently collected Magpie Fiddler Ray specimens and a geographically representative selection of Southern Fiddler Rays to determine the species status of this enigmatic ray. We found that the Magpie Fiddler Rays share a mitochondrial haplotype with 23 Southern Fiddler Rays and are not differentiated from 35 Southern Fiddler Rays at more than 4000 SNPs derived from DArTseq data. The morphological trait values that are putatively diagnostic for the Magpie Fiddler Ray fall within the range of variation observed among Southern Fiddler Rays. Our analyses are consistent with the notion that the Magpie Fiddler Ray is a rare colour and pattern variant of the widespread and abundant Southern Fiddler Ray. We also identified two hybrids between the Eastern and Southern Fiddler Rays, only the third time that hybrids have been identified in nature in chondrichthyans. Our results provide critical guidance in the assessment of its conservation status and an ending to a 60 year old conundrum for marine conservation. PMID:26250000
Identification of a Hydrolyzable Tannin, Oenothein B, as an Aluminum-Detoxifying Ligand in a Highly Aluminum-Resistant Tree, Eucalyptus camaldulensis1[C][W
Tahara, Ko; Hashida, Koh; Otsuka, Yuichiro; Ohara, Seiji; Kojima, Katsumi; Shinohara, Kenji
Eucalyptus camaldulensis is a tree species in the Myrtaceae that exhibits extremely high resistance to aluminum (Al). To explore a novel mechanism of Al resistance in plants, we examined the Al-binding ligands in roots and their role in Al resistance of E. camaldulensis. We identified a novel type of Al-binding ligand, oenothein B, which is a dimeric hydrolyzable tannin with many adjacent phenolic hydroxyl groups. Oenothein B was isolated from root extracts of E. camaldulensis by reverse-phase high-performance liquid chromatography and identified by nuclear magnetic resonance and mass spectrometry analyses. Oenothein B formed water-soluble or -insoluble complexes with Al depending on the ratio of oenothein B to Al and could bind at least four Al ions per molecule. In a bioassay using Arabidopsis (Arabidopsis thaliana), Al-induced inhibition of root elongation was completely alleviated by treatment with exogenous oenothein B, which indicated the capability of oenothein B to detoxify Al. In roots of E. camaldulensis, Al exposure enhanced the accumulation of oenothein B, especially in EDTA-extractable forms, which likely formed complexes with Al. Oenothein B was localized mostly in the root symplast, in which a considerable amount of Al accumulated. In contrast, oenothein B was not detected in three Al-sensitive species, comprising the Myrtaceae tree Melaleuca bracteata, Populus nigra, and Arabidopsis. Oenothein B content in roots of five tree species was correlated with their Al resistance. Taken together, these results suggest that internal detoxification of Al by the formation of complexes with oenothein B in roots likely contributes to the high Al resistance of E. camaldulensis. PMID:24381064
Growth inhibition of foodborne pathogens and food spoilage organisms by select raw honeys.
Mundo, Melissa A; Padilla-Zakour, Olga I; Worobo, Randy W
Twenty-seven honey samples from different floral sources and geographical locations were evaluated for their ability to inhibit the growth of seven food spoilage organisms (Alcaligenes faecalis, Aspergillus niger, Bacillus stearothermophilus, Geotrichum candidum, Lactobacillus acidophilus, Penicillium expansum, Pseudomonas fluorescens) and five foodborne pathogens (Bacillus cereus, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica Ser. Typhimurium, and Staphylococcus aureus) using an overlay inhibition assay. They were also tested for specific activity against S. aureus 9144 and B. stearothermophilus using the equivalent percent phenol test--a well diffusion assay corresponding to a dilute phenol standard curve. Honey inhibited bacterial growth due to high sugar concentration (reduced water activity), hydrogen peroxide generation, and proteinaceous compounds present in the honey. Some antibacterial activity was due to other unidentified components. The ability of honey to inhibit the growth of microorganisms varies widely, and could not be attributed to a specific floral source or demographic region produced in this study. Antibacterially active samples in this study included Montana buckwheat, tarweed, manuka, melaleuca, and saw palmetto. Furthermore, the bacteria were not uniformly affected by honey. Varying sensitivities to the antimicrobial properties were observed with four strains of S. aureus thus emphasizing the variability in the antibacterial effect of honey samples. Mold growth was not inhibited by any of the honeys tested. B. stearothermophilus, a heat-resistant spoilage bacteria, was shown to be highly sensitive to honey in both the overlay and well diffusion assays; other sensitive bacteria included A. faecalis and L. acidophilus. Non-peroxide antibacterial activity was observed in both assays; the highest instance was observed in the specific activity assay against B. stearothermophilus. Further research could indicate whether
Fumigant toxicity of plant essential oils against Camptomyia corticalis (Diptera: Cecidomyiidae).
Kim, Jun-Ran; Haribalan, Perumalsamy; Son, Bong-Ki; Ahn, Young-Joon
The toxicity of 98 plant essential oils against third instars of cecidomyiid gall midge Camptomyia corticalis (Loew) (Diptera: Cecidomyiidae) was examined using a vapor-phase mortality bioassay. Results were compared with that of a conventional insecticide dichlorvos. Based on 24-h LC50 values, all essential oils were less toxic than dichlorvos (LC50, 0.027 mg/cm3). The LC50 of caraway (Carum carvi L.) seed, armoise (Artemisia vulgaris L.), clary sage (Salvia sclarea L.), oregano (Origanum vulgare L.), lemongrass [Cymbopogon citratus (DC.) Stapf], niaouli (Melaleuca viridiflora Gaertner), spearmint (Mentha spicata L.), cassia especial (Cinnamomum cassia Nees ex Blume), Dalmatian sage (Salvia offcinalis L.), red thyme (Thymus vulgaris L.), bay [Pimenta racemosa (P. Mill.) J.W. Moore], garlic (Allium sativum L.), and pennyroyal (Mentha pulegium L.) oils is between 0.55 and 0.60 mg/cm3. The LC50 of cassia (C. cassia, pure and redistilled), white thyme (T. vulgaris), star anise (Illicium verum Hook.f.), peppermint (Mentha X piperita L.), wintergreen (Gaultheria procumbens L.), cinnamon (Cinnamomum zeylanicum Blume) bark, sweet marjoram (Origanum majorana L.), Roman chamomile [Chamaemelum nobile (L.) All.], eucalyptus (Eucalyptus globulus Labill.), rosemary (Rosmarinus officinalis L.),Virginian cedarwood (Juniperus virginiana L.), pimento berry [Pimenta dioica (L.) Merr.], summer savory (Satureja hortensis L.), lavender (Lavandula angustifolia Mill.), and coriander (Coriandrum sativum L.) oils is between 0.61 and 0.99 mg/cm3. All other essential oils tested exhibited low toxicity to the cecidomyiid larvae (LC50, >0.99 mg/cm3). Global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment justify further studies on the active essential oils as potential larvicides for the control of C. corticalis populations as fumigants with contact action. PMID:22928313
Ontogenetic changes in responses to settlement cues by Anemonefish
NASA Astrophysics Data System (ADS)
Dixson, D. L.; Munday, P. L.; Pratchett, M.; Jones, G. P.
Population connectivity for most marine species is dictated by dispersal during the pelagic larval stage. Although reef fish larvae are known to display behavioral adaptations that influence settlement site selection, little is known about the development of behavioral preferences throughout the larval phase. Whether larvae are attracted to the same sensory cues throughout their larval phase, or exhibit distinct ontogenetic shifts in sensory preference is unknown. Here, we demonstrate an ontogenetic shift in olfactory cue preferences for two species of anemonefish, a process that could aid in understanding both patterns of dispersal and settlement. Aquarium-bred naïve Amphiprion percula and A. melanopus larvae were tested for olfactory preference of relevant reef-associated chemical cues throughout the 11-day pelagic larval stage. Age posthatching had a significant effect on the preference for olfactory cues from host anemones and live corals for both species. Preferences of olfactory cues from tropical plants of A. percula, increased by approximately ninefold between hatching and settlement, with A. percula larvae showing a fivefold increase in preference for the olfactory cue produced by the grass species. Larval age had no effect on the olfactory preference for untreated seawater over the swamp-based tree Melaleuca nervosa, which was always avoided compared with blank seawater. These results indicate that reef fish larvae are capable of utilizing olfactory cues early in the larval stage and may be predisposed to disperse away from reefs, with innate olfactory preferences drawing newly hatched larvae into the pelagic environment. Toward the end of the larval phase, larvae become attracted to the olfactory cues of appropriate habitats, which may assist them in identification of and navigation toward suitable settlement sites.
Induction of Expression and Functional Activity of P-glycoprotein Efflux Transporter by Bioactive Plant Natural Products
Abuznait, Alaa H.; Qosa, Hisham; O'Connell, Nicholas D.; Akbarian-Tefaghi, Jessica; Sylvester, Paul W.; El Sayed, Khalid A.; Kaddoumi, Amal
The effect of bioactive plant natural products on the expression and functional activity of P-glycoprotein (P-gp) is poorly understood. Interactions of bioactive plant-based food and dietary supplements with P-gp can cause significant alteration of pharmacokinetic properties of P-gp substrate drugs when used in combination. This can augment toxicity and/or interfere with the drug's therapeutic outcomes. This study investigated the effects of diverse commonly used plant natural products on the expression and activity of P-gp in human adenocarcinoma cells (LS-180). These natural products included the tobacco cembranoid (1S,2E,4R,6R,7E,11E)-2,7,11-cembratriene-4,6-diol (cembratriene), the palm oil-derived γ-tocotrienol, the extra-virgin olive oil-derived secoiridoid oleocanthal, and the triterpene acid asiatic acid derived from Melaleuca ericifolia and abundant in several other common plant dietary supplements. Treatment with 25 μM of cembratriene, oleocanthal, γ-tocotrienol, or asiatic acid showed 2.3-3.0-fold increase in P-gp expression as demonstrated by Western blotting. These results were consistent with those obtained by quantitative analysis of fluorescent micrographs for P-gp. Accumulation studies demonstrated 31-38% decrease in rhodamine 123 intracellular levels when LS-180 cells were treated with the investigated compounds as a result of P-gp induction. Bioactive natural products can up-regulate the P-gp expression and functionality, which may induce herb/food-drug interactions when concomitantly used with P-gp substrate drugs. PMID:21851848
Landscape mulches and termite nutritional ecology: growth and survival of incipient colonies of Coptotermes formosanus (Isoptera: Rhinotermitidae).
Sun, Jian-Zhong
Alate swarms are one of the major visible signs of the expansion of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), in an area. Successful establishment of an incipient colony is thought to mainly rely on available food resources and moisture. The large-scale use of tree-based mulches in landscapes may inadvertently contribute to local establishment and growth of C. formosanus colonies. This research investigated the nutritional ecology of incipient colonies of C. formosanus feeding on seven tree-based, weathered, and nonweathered landscape mulches: pine straw, pine bark, cedar wood, water oak, eucalyptus, cypress, and melaleuca. Incipient colonies of C. formosanus feeding on pine straw, either weathered or nonweathered, produced significantly more progeny over the course of 1-yr feeding than colonies feeding on the other mulches tested. Regardless of weathered or not, the incipient colonies feeding on pine straw, eucalyptus, bald cypress, and water oak mulches had significantly greater survival rates after 360 d (53-77%) than colonies feeding on the other mulches tested (0-13%), but colonies feeding on nonweathered water oak had significantly lower survival (8%) than those kept on weathered water oak (58%). Colony fitness values were significantly different between the weathering treatment groups and among the different types of mulches. With regard to colony growth characteristics, three distinct growth patterns were identified: a high number of progeny (>100) with high colony survival rate (>50%), a medium number of progeny (12-50) with high colony survival rate (>50%), and a small number of progeny (0-10) with low colony survival rate (<5%). These findings suggest that different types of mulch substrates could significantly impact the nutritional ecology of the founding pairs and the successful establishment of incipient colonies during the swarming season. PMID:17461078
Feeding and Development of the Glassy-Winged Sharpshooter, Homalodisca vitripennis, on Australian Native Plant Species and Implications for Australian Biosecurity
Rathé, Anna A.; Pilkington, Leigh J.; Hoddle, Mark S.; Spohr, Lorraine J.; Daugherty, Matthew P.; Gurr, Geoff M.
In any insect invasion the presence or absence of suitable food and oviposition hosts in the invaded range is a key factor determining establishment success. The glassy-winged sharpshooter, Homalodisca vitripennis, is an important insect vector of the xylem-limited bacterial plant pathogen, Xylella fastidiosa, which causes disease in numerous host plants including food and feedstock crops, ornamentals and weeds. Both the pathogen and the vector are native to the Americas and are considered to be highly invasive. Neither has been detected in Australia. Twelve Australian native plant species present in the USA were observed over two years for suitability as H. vitripennis feeding, oviposition and nymph development hosts. Hosts providing evidence of adult or nymph presence were Leptospermum laevigatum, Acacia cowleana, Eremophila divaricata, Eucalyptus wandoo, Hakea laurina, Melaleuca laterita and Swainsona galegifolia. An oviposition-suitability field study was conducted with citrus, a favoured oviposition host, as a positive control. Citrus and L. laevigatum, A. cowleana, B. ericifolia×B. spinulosa, C. pulchella, E. divaricata, E. wandoo, H. laurina, and S. galegifolia were found to be oviposition hosts. Egg parasitism by the mymarid parasitoid Gonatocerus ashmeadi was observed on all Australian plants. A number of Australian plants that may facilitate H. vitripennis invasion have been identified and categorised as 'high risk' due to their ability to support all three life stages (egg, nymph and adult) of the insect in the field (L. laevigatum, A. cowleana, E. divaricata, H. laurina, and S. galegifolia). The implications of these host status and natural enemy research findings are discussed and placed in an Australian invasion context. PMID:24614821
Phosphorus removal from secondary sewage and septage using sand media amended with biochar in constructed wetland mesocosms.
de Rozari, P; Greenway, M; El Hanandeh, A
To improve the performance efficiency of subsurface constructed wetlands (CWs), a variety of media have been tested. Recently, there has been a rising interest in biochar. This research aims to develop the effectiveness of sand media amended with biochar and two plants species (Melaleuca quinquenervia and Cymbopogon citratus) in removing phosphorus from sewage effluent in CWs. The experimental design consisted of vertical flow (VF) mesocosms with seven media treatments based on the proportions of biochar in the sand media which ranged from 0 to 25% by volume. During the first 8months, the mesocosms were loaded with secondary clarified wastewater (SCW) then septage was used for the remaining 8months. Inflow and outflow were monitored for total phosphorus (TP) and PO4-P. Plants were harvested at the end of the experiment and TP biomass was determined. Removal efficiencies of TP in the mesocosms loaded with SCW and septage ranged from 42 to 91% and 30 to 83%, respectively. Removal efficiencies of PO4-P ranged from 43 to -92% and 35 to 85% for SCW and septage, respectively. The results revealed that the sand media performed better than the biochar-amended media; increasing the proportion of biochar in the media decreased removal efficiency of phosphorus. However, after flushing due to major rain event, there was no significant difference between sand and sand augmented with 20% biochar. Total plant P ranged from 1.75g in the 20% biochar mesocosm to 2.10g in the sand only mesocosm. Plant uptake of P, at least in part, may be accredited for the better P removal efficiency in the sand media compared to the biochar-amended media. PMID:27341113
Investigating the host-range of the rust fungus Puccinia psidii sensu lato across tribes of the family Myrtaceae present in Australia.
Morin, Louise; Aveyard, Ruth; Lidbetter, Jonathan R; Wilson, Peter G
The exotic rust fungus Puccinia psidii sensu lato was first detected in Australia in April 2010. This study aimed to determine the host-range potential of this accession of the rust by testing its pathogenicity on plants of 122 taxa, representative of the 15 tribes of the subfamily Myrtoideae in the family Myrtaceae. Each taxon was tested in two separate trials (unless indicated otherwise) that comprised up to five replicates per taxon and six replicates of a positive control (Syzygium jambos). No visible symptoms were observed on the following four taxa in either trial: Eucalyptus grandis×camaldulensis, E. moluccana, Lophostemon confertus and Sannantha angusta. Only small chlorotic or necrotic flecks without any uredinia (rust fruiting bodies) were observed on inoculated leaves of seven other taxa (Acca sellowiana, Corymbia calophylla 'Rosea', Lophostemon suaveolens, Psidium cattleyanum, P. guajava 'Hawaiian' and 'Indian', Syzygium unipunctatum). Fully-developed uredinia were observed on all replicates across both trials of 28 taxa from 8 tribes belonging to the following 17 genera: Agonis, Austromyrtus, Beaufortia, Callistemon, Calothamnus, Chamelaucium, Darwinia, Eucalyptus, Gossia, Kunzea, Leptospermum, Melaleuca, Metrosideros, Syzygium, Thryptomene, Tristania, Verticordia. In contrast, the remaining 83 taxa inoculated, including the majority of Corymbia and Eucalyptus species, developed a broad range of symptoms, often across the full spectrum, from fully-developed uredinia to no visible symptoms. These results were encouraging as they indicate that some levels of genetic resistance to the rust possibly exist in these taxa. Overall, our results indicated no apparent association between the presence or absence of disease symptoms and the phylogenetic relatedness of taxa. It is most likely that the majority of the thousands of Myrtaceae species found in Australia have the potential to become infected to some degree by the rust, although this wide host range may
Investigating the Host-Range of the Rust Fungus Puccinia psidii sensu lato across Tribes of the Family Myrtaceae Present in Australia
Morin, Louise; Aveyard, Ruth; Lidbetter, Jonathan R.; Wilson, Peter G.
The exotic rust fungus Puccinia psidii sensu lato was first detected in Australia in April 2010. This study aimed to determine the host-range potential of this accession of the rust by testing its pathogenicity on plants of 122 taxa, representative of the 15 tribes of the subfamily Myrtoideae in the family Myrtaceae. Each taxon was tested in two separate trials (unless indicated otherwise) that comprised up to five replicates per taxon and six replicates of a positive control (Syzygium jambos). No visible symptoms were observed on the following four taxa in either trial: Eucalyptus grandis×camaldulensis, E. moluccana, Lophostemon confertus and Sannantha angusta. Only small chlorotic or necrotic flecks without any uredinia (rust fruiting bodies) were observed on inoculated leaves of seven other taxa (Acca sellowiana, Corymbia calophylla 'Rosea', Lophostemon suaveolens, Psidium cattleyanum, P. guajava 'Hawaiian' and 'Indian', Syzygium unipunctatum). Fully-developed uredinia were observed on all replicates across both trials of 28 taxa from 8 tribes belonging to the following 17 genera: Agonis, Austromyrtus, Beaufortia, Callistemon, Calothamnus, Chamelaucium, Darwinia, Eucalyptus, Gossia, Kunzea, Leptospermum, Melaleuca, Metrosideros, Syzygium, Thryptomene, Tristania, Verticordia. In contrast, the remaining 83 taxa inoculated, including the majority of Corymbia and Eucalyptus species, developed a broad range of symptoms, often across the full spectrum, from fully-developed uredinia to no visible symptoms. These results were encouraging as they indicate that some levels of genetic resistance to the rust possibly exist in these taxa. Overall, our results indicated no apparent association between the presence or absence of disease symptoms and the phylogenetic relatedness of taxa. It is most likely that the majority of the thousands of Myrtaceae species found in Australia have the potential to become infected to some degree by the rust, although this wide
Shifts in symbiotic associations in plants capable of forming multiple root symbioses across a long-term soil chronosequence.
Albornoz, Felipe E; Lambers, Hans; Turner, Benjamin L; Teste, François P; Laliberté, Etienne
Changes in soil nutrient availability during long-term ecosystem development influence the relative abundances of plant species with different nutrient-acquisition strategies. These changes in strategies are observed at the community level, but whether they also occur within individual species remains unknown. Plant species forming multiple root symbioses with arbuscular mycorrhizal (AM) fungi, ectomycorrhizal (ECM) fungi, and nitrogen-(N) fixing microorganisms provide valuable model systems to examine edaphic controls on symbioses related to nutrient acquisition, while simultaneously controlling for plant host identity. We grew two co-occurring species, Acacia rostellifera (N2-fixing and dual AM and ECM symbioses) and Melaleuca systena (AM and ECM dual symbioses), in three soils of contrasting ages (c. 0.1, 1, and 120 ka) collected along a long-term dune chronosequence in southwestern Australia. The soils differ in the type and strength of nutrient limitation, with primary productivity being limited by N (0.1 ka), co-limited by N and phosphorus (P) (1 ka), and by P (120 ka). We hypothesized that (i) within-species root colonization shifts from AM to ECM with increasing soil age, and that (ii) nodulation declines with increasing soil age, reflecting the shift from N to P limitation along the chronosequence. In both species, we observed a shift from AM to ECM root colonization with increasing soil age. In addition, nodulation in A. rostellifera declined with increasing soil age, consistent with a shift from N to P limitation. Shifts from AM to ECM root colonization reflect strengthening P limitation and an increasing proportion of total soil P in organic forms in older soils. This might occur because ECM fungi can access organic P via extracellular phosphatases, while AM fungi do not use organic P. Our results show that plants can shift their resource allocation to different root symbionts depending on nutrient availability during ecosystem development. PMID
Feeding and development of the glassy-winged sharpshooter, Homalodisca vitripennis, on Australian native plant species and implications for Australian biosecurity.
Rathé, Anna A; Pilkington, Leigh J; Hoddle, Mark S; Spohr, Lorraine J; Daugherty, Matthew P; Gurr, Geoff M
In any insect invasion the presence or absence of suitable food and oviposition hosts in the invaded range is a key factor determining establishment success. The glassy-winged sharpshooter, Homalodisca vitripennis, is an important insect vector of the xylem-limited bacterial plant pathogen, Xylella fastidiosa, which causes disease in numerous host plants including food and feedstock crops, ornamentals and weeds. Both the pathogen and the vector are native to the Americas and are considered to be highly invasive. Neither has been detected in Australia. Twelve Australian native plant species present in the USA were observed over two years for suitability as H. vitripennis feeding, oviposition and nymph development hosts. Hosts providing evidence of adult or nymph presence were Leptospermum laevigatum, Acacia cowleana, Eremophila divaricata, Eucalyptus wandoo, Hakea laurina, Melaleuca laterita and Swainsona galegifolia. An oviposition-suitability field study was conducted with citrus, a favoured oviposition host, as a positive control. Citrus and L. laevigatum, A. cowleana, B. ericifolia×B. spinulosa, C. pulchella, E. divaricata, E. wandoo, H. laurina, and S. galegifolia were found to be oviposition hosts. Egg parasitism by the mymarid parasitoid Gonatocerus ashmeadi was observed on all Australian plants. A number of Australian plants that may facilitate H. vitripennis invasion have been identified and categorised as 'high risk' due to their ability to support all three life stages (egg, nymph and adult) of the insect in the field (L. laevigatum, A. cowleana, E. divaricata, H. laurina, and S. galegifolia). The implications of these host status and natural enemy research findings are discussed and placed in an Australian invasion context. PMID:24614821
The role of vegetation in the formation of anabranching channels in an ephemeral river, Northern plains, arid central Australia
NASA Astrophysics Data System (ADS)
Tooth, Stephen; Nanson, Gerald C.
As the distribution and abundance of vegetation in drylands is often controlled by the greater availability of water along river channels, riparian vegetation has the potential to influence significantly dryland river form, process and behaviour. This paper demonstrates how a small indigenous shrub, the inland teatree (Melaleuca glomerata), influences the formation and maintenance of anabranching channels in a reach of the ephemeral Marshall River, Northern Plains, arid central Australia. Here, the Marshall is characterized by ridge-form anabranching, where water and sediment are routed through subparallel, multiple channels of variable size which occur within a typically straight channel-train. Channels are separated by channel-train ridges - narrow, flow-aligned, vegetated features - or by wider islands. By providing a substantial element of boundary roughness, dense stands of teatrees growing on channel beds or atop the ridges and islands influence flow velocities, flow depths and sediment transport, resulting in flow diversion, bank and floodplain erosion, and especially sediment deposition. Ridges and islands represent a continuum of forms, and their formation and development can be divided into a three-stage sequence involving teatree growth and alluvial sedimentation.1Teatrees colonize a flat, sandy channel bed, initiating the formation of ridges by lee-side accretion. Individual ridges grow laterally, vertically and longitudinally and maintain a geometrically similar streamlined (lemniscate) form that presents minimum drag.2Individual ridges grow in size, and interact with neighbouring ridges, causing the lemniscate forms to become distorted. Ridges in the lee of other ridges tend to be protected from the erosive effects of floods and survive, whereas individual teatrees or small ridges exposed to flow concentrated between larger ridges, tend to be removed.3
Diversity and composition of sediment bacteria in subtropical coastal wetlands of North Stradbroke Island, Queensland, Australia
NASA Astrophysics Data System (ADS)
Chuvochina, Maria; Sampayo, Eugenia; Welti, Nina; Hayes, Matthew; Lu, Yang; Lovelock, Catherine; Lockington, David
Coastal wetlands provide a wide variety of important ecosystem services but continue to suffer disturbance, degradation and deforestation. Sediment bacteria are responsible for major nutrient transformation and recycling in these ecosystems. Insight into microbial community composition and the factors that determine them may improve our understanding of biogeochemical processes, food web dynamics, biodegradation processes and, thus, help to develop the management strategies for preserving the ecosystem health and services. Characterizing shifts in community taxa along environmental gradients has been shown to provide a useful tool for determining the major drivers affecting community structure and function. North Stradbroke Island (NSI) in Southern Queensland presents considerable habitat diversity including variety of groundwater dependent ecosystems such as lakes, swamps, sedge-like salt marshes and mangroves. Ecological responses of continuous groundwater extraction for municipal purposes and sand mining operations on NSI are still need to be assessed in order to protect its unique environment. Changes in coastal hydrology due to either climate change or human activity may directly affect microbial populations and, thus, biogeochemical cycles of nutrients. These may result in altering/losing some ecosystem services provided by coastal wetlands. In this study we examine microbial diversity and determine environmental controls on bacterial community structure along a natural transition from freshwater forested wetland (melaleuca woodland), sedge-like salt marsh and into mangroves located at NSI. The study area is characterized by significant groundwater flow, nutrient limitation and sharp transition from one ecosystem type to another. Sediment cores (0-5 cm and 20-25 cm depth) were collected from three representative sites of each zone (mangroves - salt marsh - freshwater wetland) along the salinity gradient in August 2012. Subsamples were set aside for use in
Protein tyrosine phosphatase 1B inhibitory activity of Indonesian herbal medicines and constituents of Cinnamomum burmannii and Zingiber aromaticum.
Saifudin, Azis; Kadota, Shigetoshi; Tezuka, Yasuhiro
We screened water and methanol extracts of 28 Indonesian medicinal plants for their protein tyrosine phosphatase 1B (PTP1B) inhibitory activities. Nine water extracts, i.e., Alstonia scholaris leaf, Blumea balsamifera, Cinnamomum burmannii, Cymbopogon nardus, Melaleuca leucadendra, Phyllanthus niruri, Piper nigrum, Syzygium aromaticum, and Sy. polyanthum, exhibited ≥70 % inhibition at 25 μg/mL, whereas 11 methanol extracts, i.e., Als. scholaris, Andrographis paniculata, B. balsamifera, Ci. burmannii, Curcuma heyneana, Glycyrrhiza glabra, M. leucadendra, Punica granatum, Rheum palmatum, Sy. polyanthum, and Z. aromaticum, exhibited ≥70 % inhibition at 25 μg/mL. Water extracts of B. balsamifera (IC50, 2.26 μg/mL) and M. leucadendra (IC50, 2.05 μg/mL), and methanol extracts of Ci. burmannii (IC50, 2.47 μg/mL), Pu. granatum (IC50, 2.40 μg/mL), and Sy. polyanthum (IC50, 1.03 μg/mL) exhibited strong inhibitory activity, which was comparable with that of the positive control, RK-682 (IC50, 2.05 μg/mL). The PTP1B inhibitory activity of the constituents of Ci. burmannii and Z. aromaticum was then evaluated. 5'-Hydroxy-5-hydroxymethyl-4″,5″-methylenedioxy-1,2,3,4-dibenzo-1,3,5-cycloheptatriene (2; IC50, 29.7 μM) and trans-cinnamaldehyde (5; IC50, 57.6 μM) were the active constituents of Ci. burmannii, while humulatrien-5-ol-8-one (21; IC50, 27.7 μM), kaempferol-3,4'-di-O-methyl ether (32; IC50, 17.5 μM), and (S)-6-gingerol (33; IC50, 28.1 μM) were those of Z. aromaticum. These results suggest that these medicinal plants may contribute to the treatment and/or prevention of type II diabetes and/or obesity through PTP1B inhibition. PMID:22645080
Monitoring flooding and vegetation on seasonally inundated floodplains with multifrequency polarimetric synthetic aperture radar
NASA Astrophysics Data System (ADS)
Hess, Laura Lorraine
The ability of synthetic aperture radar to detect flooding and vegetation structure was evaluated for three seasonally inundated floodplain sites supporting a broad variety of wetland and upland vegetation types: two reaches of the Solimoes floodplain in the central Amazon, and the Magela Creek floodplain in Northern Territory, Australia. For each site, C- and L-band polarimetric Shuttle Imaging Radar-C (SIR-C) data was obtained at both high- and low-water stages. Inundation status and vegetation structure were documented simultaneous with the SIR-C acquisitions using low-altitude videography and ground measurements. SIR-C images were classified into cover states defined by vegetation physiognomy and presence of standing water, using a decision-tree model with backscattering coefficients at HH, VV, and HV polarizations as input variables. Classification accuracy was assessed using user's accuracy, producer's accuracy, and kappa coefficient for a test population of pixels. At all sites, both C- and L-band were necessary to accurately classify cover types with two dates. HH polarization was most. useful for distinguishing flooded from non-flooded vegetation (C-HH for macrophyte versus pasture, L-HH for flooded versus non-flooded forest), and cross-polarized L-band data provided the best separation between woody and non-woody vegetation. Increases in L-HH backscattering due to flooding were on the order of 3--4 dB for closed-canopy varzea and igapo forest, and 4--7 dB, for open Melaleuca woodland. The broad range of physiognomies and stand structures found in both herbaceous and woody wetland communities, combined with the variation in the amount of emergent canopy caused by water level fluctuations and phenologic changes, resulted in a large range in backscattering characteristics of wetland communities both within and between sites. High accuracies cannot be achieved for these communities using single-date, single-band, single-polarization data, particularly in the
Acaricidal and Insecticidal Activities of Essential Oils against a Stored-Food Mite and Stored-Grain Insects.
Song, Ja-Eun; Kim, Jeong-Moon; Lee, Na-Hyun; Yang, Ji-Yeon; Lee, Hoi-Seon
Twenty plant-derived oils were evaluated for their acaricidal and insecticidal activities against Sitotroga cerealella, Sitophilus oryzae, Sitophilus zeamais, and Tyrophagus putrescentiae adults, by using the fumigant and filter paper diffusion methods. Responses varied with bioassay systems, insect or mite species, plant oils, and exposure time. Based on the 50% lethal dose (LD50) values against S. oryzae and S. zeamais in the fumigant bioassay, Anethum graveolens oil (4.12 and 1.12 μg/cm(3), respectively) induced the highest mortality, followed by Achillea millefolium (21.92 and 14.91 μg/cm(3)) and Eucalyptus dives (28.02 and 24.02 μg/cm(3)) oils, respectively. The most toxic oil based on the 50% lethal concentration values against T. putrescentiae was E. dives (3.13 μg/cm(3)), followed by Melaleuca leucadendron (3.93 μg/cm(3)) and Leptospermum pertersonii (4.41 μg/cm(3)). Neroli birgard oil (1.70 μg/cm(3)) was the most toxic based on the LD50 values against S. cerealella, followed by Citrus aurantium (1.80 μg/cm(3)) and Artemisia vulgaris (1.81 μg/cm(3)). The insecticidal and acaricidal activities of the plant oils in the filter paper diffusion bioassay were similar to those in the fumigant bioassay. In comparison, A. millefolium, A. graveolens, and E. dives oils were more effective against S. oryzae and S. zeamais in the fumigant bioassay than in the contact bioassay. These results indicate that the insecticidal activity of the three plant oils against S. oryzae and S. zeamais may be due to their fumigant action. Acaricidal activities of the A. millefolium, A. graveolens, and E. dives oils against T. putrescentiae were 2.62, 1.11, and 122 times higher than that of benzyl benzoate in the contact bioassay. These results indicate that A. millefolium, A. graveolens, and E. dives oils have potential for development as agents to control stored-grain insects and mites. PMID:26735047
Plant Ecology of Australia's Tropical Floodplain Wetlands: A Review
• Aims Despite the biodiversity values of the freshwater floodplains of northern Australia being widely recognized, there has not been a concomitant investment in developing the extent of knowledge of the basic functions and ecological processes that underpin the ecological character of these habitats. This review addresses the extent of our knowledge on the plant ecology of these wetlands and covers: the relationships between the climate and the hydrological regime on the floodplain; the vegetation patterns, succession and adaptation; and primary production. • Scope Information is available on the seasonal, but less regularly on the inter-annual, dynamics of the macrophytic vegetation and its evident inter-relationship with the extent, depth and duration of inundation by seasonal flooding. The available scientifically collected information on plant distribution and relationship with the water regime could be complemented by more attention to traditional knowledge. The productivity of the vegetation is high—the dominant wetland grass species have an annual dry weight production of 0·5–2·1 kg m−2 and the surrounding riparian (Melaleuca) trees contribute litterfall of 0·7–1·5 kg (dry weight) m−2 year−1, ∼70 % due to leaf-fall. The availability of dissolved oxygen in the water is known to vary diurnally and seasonally, at least in some habitats. The importance of seasonal differences in the availability of dissolved oxygen for the growth of micro- and macrophytic vegetation has not been investigated. The seasonal distribution and growth of plant species on a few floodplains have been investigated, and maps at scales of 1 : 10 000 to 1 : 100 000 are available for these. However, only on a few occasions have longer term analyses been conducted and long-term changes in the vegetation measured and assessed. Species lists and categorization of growth strategies and forms are available and provide a basis for further ecological
Impacts of artificial inundation of ephemeral creek beds on mature riparian eucalypts in semi-arid northwest Australia
NASA Astrophysics Data System (ADS)
Argus, Rachel; Page, Gerald; Grierson, Pauline
The resilience of riparian ecosystems of intermittent rivers to changes in their hydrological regimes is not well understood. In the Pilbara region of northwest Australia, streams flow only occasionally, reflecting a highly dynamic and extremely variable cycle of prolonged droughts punctuated by occasional floods. However, discharge of ground water pumped from mining activities over recent years has resulted in localised areas with constant surface water. Here we sought to assess impacts of prolonged saturation on the health and functioning of two co-occurring eucalypts (Eucalyptus camaldulensis and Eucalyptus victrix). While riparian vegetation is clearly adapted to partial root-zone hypoxia, we hypothesised that trees in inundated areas experience reduced root function due to an energy crisis, which will be reflected by symptoms in the foliage. We expected that complete saturation of the entire root system for an extended time period reduces physiological function through lower stomatal conductance and more negative water potential, results in canopy sparseness and reduces accumulation of foliar nitrogen and phosphorus. Trees (n=26) were assessed at two sites with artificially permanent surface water (discharge sites) and compared to trees (n=21) at a site with a naturally occurring permanent groundwater fed pool ('reference site'). Trees were sampled from a range of positions including the stream bed, the lower bank and the upper bank, in order to determine the extent of influence of the discharge water. No eucalypts grew in the stream bed at the reference site, indicating either the stream bed conditions were unsuitable for seedling survival or eucalypts were outcompeted by the flood tolerant tree Melaleuca argentea (which was absent from the impact sites). Soil redox potential, an indicator of oxygen availability and other soil chemical conditions, was measured with platinum redox probes at 25 cm depth. Trees were assessed for canopy cover, foliage water
Vegetation-induced soil water repellency as a strategy in arid ecosystems. A geochemical approach in Banksia woodlands (SW Australia)
NASA Astrophysics Data System (ADS)
Muñoz-Rojas, Miriam; Jiménez-Morillo, Nicasio T.; González-Pérez, Jose Antonio; Zavala, Lorena M.; Stevens, Jason; Jordan, Antonio
Introduction Banksia woodlands (BW) are iconic ecosystems of Western Australia (WA) composed by an overstorey dominated by Proteaceae, e.g. Banksia menziesii and Banksia attenuata, in combination with other species, such as Eucalyptus spp., Verticordia spp. or Melaleuca spp. Although located in very poor dune soils, BW provide numerous ecosystem services and sustain a high biodiversity. In this area, annual rainfall is relatively high (about 800 mm) but permeability of the sandy substrate leads to a functionally arid ecosystem. Currently, BW are threatened by sand mining activities and urban expansion; therefore conservation and restoration of these woodlands are critical. Despite numerous efforts, the success of restoration plans is usually poor mostly due to the high sensitivity to drought stress and poor seedling survival rates (5-30%) (Benigno et al., 2014). A characteristic feature of BW is their root architecture, formed by a proteoid (cluster) system that spreads to form thick mats below the soil surface, favouring the uptake of nutrients (especially, P), and preventing soil erosion. Root exudates are related to numerous plant functions, as they facilitate penetration of roots in soil and enhance the extraction of scarce mineral nutrients and its further assimilation. Exudates may also interact directly with soil or indirectly through microbial mediated events being also related to soil water repellency (SWR; Lozano et al, 2014). Knowledge about the specific compounds able to induce SWR is limited (Doerr et al., 2000), but it is generally accepted that is caused by organic molecules coating the surface of soil mineral particles and aggregates (Jordán et al., 2013). Proteaceae release short-chained organic acids to enhance phosphate acquisition, which have been also reported to be related with SWR (Jiménez-Morillo et al., 2014). It is hypothesized that disruption of water dynamics in mature BW soils is underlying the failure of restoration plans. This
Vegetation-induced soil water repellency as a strategy in arid ecosystems. A geochemical approach in Banksia woodlands (SW Australia)
NASA Astrophysics Data System (ADS)
Muñoz-Rojas, Miriam; Jiménez-Morillo, Nicasio T.; González-Pérez, Jose Antonio; Zavala, Lorena M.; Stevens, Jason; Jordan, Antonio
Introduction Banksia woodlands (BW) are iconic ecosystems of Western Australia (WA) composed by an overstorey dominated by Proteaceae, e.g. Banksia menziesii and Banksia attenuata, in combination with other species, such as Eucalyptus spp., Verticordia spp. or Melaleuca spp. Although located in very poor dune soils, BW provide numerous ecosystem services and sustain a high biodiversity. In this area, annual rainfall is relatively high (about 800 mm) but permeability of the sandy substrate leads to a functionally arid ecosystem. Currently, BW are threatened by sand mining activities and urban expansion; therefore conservation and restoration of these woodlands are critical. Despite numerous efforts, the success of restoration plans is usually poor mostly due to the high sensitivity to drought stress and poor seedling survival rates (5-30%) (Benigno et al., 2014). A characteristic feature of BW is their root architecture, formed by a proteoid (cluster) system that spreads to form thick mats below the soil surface, favouring the uptake of nutrients (especially, P), and preventing soil erosion. Root exudates are related to numerous plant functions, as they facilitate penetration of roots in soil and enhance the extraction of scarce mineral nutrients and its further assimilation. Exudates may also interact directly with soil or indirectly through microbial mediated events being also related to soil water repellency (SWR; Lozano et al, 2014). Knowledge about the specific compounds able to induce SWR is limited (Doerr et al., 2000), but it is generally accepted that is caused by organic molecules coating the surface of soil mineral particles and aggregates (Jordán et al., 2013). Proteaceae release short-chained organic acids to enhance phosphate acquisition, which have been also reported to be related with SWR (Jiménez-Morillo et al., 2014). It is hypothesized that disruption of water dynamics in mature BW soils is underlying the failure of restoration plans. This