text:
Investigation of extracts from (Tunisian) Cyperus rotundus as antimutagens and radical scavengers.
ABSTRACT This study evaluates mutagenic and antimutagenic effects of aqueous, total oligomers flavonoïds (TOF), ethyl acetate and methanol extracts from aerial parts of Cyperus rotundus with the Salmonella typhimurium assay system. The different extracts showed no mutagenicity when tested with Salmonella typhimurium strains TA98, TA100, TA1535 and TA1538 either with or without the S9 mix. On the other hand, our results showed that all extracts have antimutagenic activity against Aflatoxin B1 (AFB1) in TA100 and TA98 assay system, and against sodium azide in TA100 and TA1535 assay system. TOF, ethyl acetate and methanol extracts exhibited the highest inhibition level of the Ames response induced by the indirect mutagen AFB1. Whereas, ethyl acetate and methanol extracts exhibited the highest level of protection towards the direct mutagen, sodium azide, induced response. In addition to antimutagenic activity, these extracts showed an important free radical scavenging activity towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. TOF, ethyl acetate and methanol extracts showed IC(50) value of 15, 14 and 20μg/ml, respectively. Taken together, our finding showed that C. rotundus exhibits significant antioxidant and antimutagenic activities.
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ABSTRACT: This study evaluates genotoxic and antigenotoxic effects of extracts from leaves of Moricandia arvensis, which are used in traditional cooking and medicines. Extracts showed no genotoxicity when tested with the SOS Chromotest using E. coli PQ37 and PQ35 strains, except for the total oligomers flavonoids enriched extract. Petroleum ether and methanol extracts are the most active in reducing nitrofurantoin genotoxicity, whereas methanol and total oligomers flavonoids enriched extracts showed the most important inhibitory effect of H2O2 genotoxicity. In addition, these two extracts showed important free radical scavenging activity toward the DPPH. radical, whereas the chloroform extract exhibited the highest value of TEAC against ABTS+. radical.Drug and Chemical Toxicology 02/2007; 30(4):361-82. · 1.29 Impact Factor
Article: Dental Calculus Reveals Unique Insights into Food Items, Cooking and Plant Processing in Prehistoric Central Sudan.[Show abstract] [Hide abstract]
ABSTRACT: Accessing information on plant consumption before the adoption of agriculture is challenging. However, there is growing evidence for use of locally available wild plants from an increasing number of pre-agrarian sites, suggesting broad ecological knowledge. The extraction of chemical compounds and microfossils from dental calculus removed from ancient teeth offers an entirely new perspective on dietary reconstruction, as it provides empirical results on material that is already in the mouth. Here we present a suite of results from the multi-period Central Sudanese site of Al Khiday. We demonstrate the ingestion in both pre-agricultural and agricultural periods of Cyperus rotundus tubers. This plant is a good source of carbohydrates and has many useful medicinal and aromatic qualities, though today it is considered to be the world's most costly weed. Its ability to inhibit Streptococcus mutans may have contributed to the unexpectedly low level of caries found in the agricultural population. Other evidence extracted from the dental calculus includes smoke inhalation, dry (roasting) and wet (heating in water) cooking, a second plant possibly from the Triticaceae tribe and plant fibres suggestive of raw material preparation through chewing.PLoS ONE 07/2014; 9(7):e100808. · 3.53 Impact Factor
Article: Mutagenic, antimutagenic, cytotoxic, and apoptotic activities of extracts from Pituranthos tortuosus.[Show abstract] [Hide abstract]
ABSTRACT: Mutagenic and antimutagenic activities against direct acting mutagens, nifuroxazide (NF) and sodium azide (SA), and indirect acting mutagen aflatoxin B1 (AFB1) of extracts prepared from aerial parts of Pituranthos tortuosus were investigated in bacterial assay systems (i.e., the Ames test with Salmonella typhimurium TA100, TA98, TA1538, TA1535, and the SOS chromotest with Escherichia coli PQ 37). It was found that all extracts obtained from P. tortuosus decreased the mutagenicity induced by AFB1 (10 microg/assay), SA (1.5 microg/assay), and NF (20 microg/assay). Ethyl acetate, acetone, methanol, and total oligomer flavenoid extracts exhibited the highest inhibition level of mutagenicity induced by the indirect mutagen AFB1. In addition, antiproliferative and apoptotic properties of these extracts have also been reported using two leukemia cell lines, L1210 and K562. The results revealed that all extracts showed a significant cytotoxic effect on these cell lines, and the effect was greater in the presence of human K562 chronic myelogenous leukemia cells, whereas they do not induce apoptosis.Drug and Chemical Toxicology 02/2008; 31(1):37-60. · 1.29 Impact Factor
Page 1
Environmental Toxicology and Pharmacology 20 (2005) 478–484
Investigation of extracts from (Tunisian) Cyperus rotundus as
antimutagens and radical scavengers
Soumaya Kilania,c, Ribai Ben Ammara,b, In` es Bouhlela,b, Afef Abdelwaheda,c,
Nawel Haydera,c, Amor Mahmoudb, Kamel Ghedirab, Leila Chekir-Ghediraa,c,∗
aDepartment of Biochemistry and Molecular Biology, Faculty of Pharmacy, Rue Avicenne, Monastir 5000, Tunisia
bDepartment of Pharmacognosy, Faculty of Pharmacy, Rue Avicenne, Monastir 5000, Tunisia
cDepartment of Molecular and Cellular Biology, Faculty of Dental Medicine, Rue Avicenne, Monastir 5000, Tunisia
Received 4 February 2005; accepted 23 May 2005
Available online 26 July 2005
Thisstudyevaluatesmutagenicandantimutageniceffectsofaqueous,totaloligomersflavono¨ ıds(TOF),ethylacetateandmethanolextracts
from aerial parts of Cyperus rotundus with the Salmonella typhimurium assay system.
The different extracts showed no mutagenicity when tested with Salmonella typhimurium strains TA98, TA100, TA1535 and TA1538 either
with or without the S9 mix. On the other hand, our results showed that all extracts have antimutagenic activity against Aflatoxin B1 (AFB1)
in TA100 and TA98 assay system, and against sodium azide in TA100 and TA1535 assay system. TOF, ethyl acetate and methanol extracts
exhibited the highest inhibition level of the Ames response induced by the indirect mutagen AFB1. Whereas, ethyl acetate and methanol
extracts exhibited the highest level of protection towards the direct mutagen, sodium azide, induced response. In addition to antimutagenic
activity, these extracts showed an important free radical scavenging activity towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical.
TOF, ethyl acetate and methanol extracts showed IC50value of 15, 14 and 20?g/ml, respectively.
Taken together, our finding showed that C. rotundus exhibits significant antioxidant and antimutagenic activities.
© 2005 Elsevier B.V. All rights reserved.
Keywords: Cyperus rotundus; Ames test; Mutagenic effect; Antimutagenic activity; Free radical scavenging effect
1. Introduction
Since ancient times, several diseases have been treated by
(Pezzoto, 1997). Investigation of traditionally used medici-
nal plants is thus valuable on two levels, firstly, as a source of
microorganisms provide the pharmaceutical industry with
some of the most important sources of components for the
research of new medications. In the last few decades much
study has been directed at popular medicine, with the aim
∗Corresponding author. Tel.: +216 97 3162 82; fax: +216 73 461150.
E-mail address: email@example.com (L. Chekir-Ghedira).
of identifying natural products with therapeutic properties
C. rotundus Linn, a sedge of the family of Cyperaceae,
order cyperales, is widely distributed in the Mediterranean
basin areas. This plant, which grows naturally in tropical,
Center and South (Gab´ es) of Tunisia (Cu´ enod, 1954). C.
rotundus is a traditional medicinal plant appearing among
Indian, Chinese and Japanese natural drugs, used for the
treatment of spasms stomach disorder and anti-inflammatory
diseases (Gupta et al., 1971; Seo et al., 2001). Zhu et al.
plant showed in vitro antimalarial activity (Thebtaranonth
et al., 1995). Other pharmacological investigations indicated
1382-6689/$ – see front matter © 2005 Elsevier B.V. All rights reserved.
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S. Kilani et al. / Environmental Toxicology and Pharmacology 20 (2005) 478–484
that C. rotundus, had remarkable hypotensive (Li, 1992) and
antipyretic effects (Vedavathy and Rao, 1990). However,
adverse effects of medicinal plants are not well documented.
The aim of this work was the assessment of mutagenicity,
antimutagenicity and free radical scavenging activity in
extracts isolated from aerial parts (leaves and flowers) of
C. rotundus. In this study we reported antioxidant and
antimutagenic properties, of few extracts from C. rotundus,
which could be eventually used as potential agents in
2. Materials and methods
2.1. Chemicals
ThemutagensAflatoxinB1(AFB 1)and2-
aminoanthracene (2-AA) were purchased from Sigma
(USA). Sodium azide (SA) and 2-nitrofluorene (2-NF) were
purchased from Aldrich (USA).
1,1-Diphenyl-2-picrylhydrazyl (DPPH) and ?-tocopherol
were purchased from Aldrich, USA. Histidine, biotine and
Agar–Agar from Difco. Aroclor 1254 was purchased from
2.2. Plant material
Aerial parts (leaves and flowers) of C. rotundus. L were
harvested in the region of Monastir in the Center of Tunisia
in October 2002. Botanical identification was carried out by
Pr Chaieb (Department of Botany, Faculty of Sciences, Uni-
versity of Sfax, Tunisia), according to the flora of Tunisia
(Cu´ enod, 1954). A voucher specimen (CP-10.02) has been
deposited in the Laboratory of Pharmacognosy, Faculty of
Pharmacy of Monastir, Tunisia.
2.3. Preparation of plant extracts
Fresh aerial parts of C. rotundus, were dried at room
temperature and reduced to coarse powder. The powdered
leaves were extracted by boiling water for 15–20min. The
crude extract obtained was filtered and lyophilized (aqueous
extract). The residue was dissolved in water.
In order to obtain an extract enriched with total oligomers
flavonoids (TOF), powder was macerated in water/acetone
mixture (1/2, v/v), during 24h with continuous stirring. The
extract was filtered and the acetone was evaporated under
low pressure in order to obtain an aqueous phase. The tan-
nins were removed by precipitation with an excess of NaCl
during 24h at 5◦C, than we recovered the supernatant. This
latter was extracted with ethyl acetate, concentrated and pre-
cipitated with an excess of chloroform. The precipitate was
separated and yielded TOF extract which was dissolved in
water (Ghedira et al., 1991).
Ethyl acetate and methanol extracts were obtained by
soxhlet extraction (6h). The two types of extract, with differ-
ent polarities were concentrated to dryness and the residue
was kept at 4◦C. These two extracts were resuspended in
DMSO. In the present study, four extracts were investi-
gated. The doses of extracts we tested in both Salmonella-
microsome assay (500, 200 and 50?g/plate) and DPPH
scavenging assay (100, 30, 10, 3, and 1?g/ml) are in accor-
dance with our previous investigations (Hayder et al., 2003,
2004; Kilani et al., 2005) where a number of preliminary
dose-finding tests involving a number of plant extracts were
conducted. This means that the doses were suitable for test-
ing the majority of the extracts, however, not necessarily all.
Therefore, some extracts may be toxic at one or more of the
applied doses.
2.4. Bacterial strains
Salmonella typhimurium strains TA100, TA1535, TA98
and TA1538 witch are histidine-requiring mutants, were
kindly provided by Pr. Felzen, (UERJ, Brazil), and main-
tained as described by Maron and Ames (1983). The geno-
types of the test strains were checked routinely for their
histidine requirement, deep rough (rfa) character, UV sen-
sitivity (uvrB mutation) and presence of the R factor. They
were stored at −80◦C.
Salmonella typhimurium TA98 and TA1538 strains
are frame-shift sensitive strains which contain the same
hisD3052 mutation. Unlike strain TA1538, strain TA98 con-
tains the plasmid pKM 101, and the products of the mucAB
genes on this plasmid enhance SOS mutagenesis, thereby
making strain TA98 more responsive to certain mutagens
than strain TA1538 (Maron and Ames, 1983). TA1538 was
only used for mutagenicity study. Salmonella typhimurium
TA1535 and TA100 strains contain the same base-pair sub-
stitution mutation hisG46 (Zeiger et al., 1985).
Salmonella typhimurium TA98, TA100 and TA1535
strains are known to be more responsive to certain muta-
gens as AFB1 (for TA98 and TA100 strains) and sodium
azide (for TA100 and TA1535 strains) (Maron and Ames,
2.5. Preliminary phytochemical analysis
Plant materials were screened for the presence of tannins,
flavonoids, coumarins and sterols, using the methods previ-
ously described by Tona et al. (1998, 2004).
Two milligrams of each extract was separately dissolved
in 2ml of the adequate solvent. The identification of major
chemical groups was carried out by thin layer chromatog-
raphy (TLC) on silica gel 60 F254 Merck (layer thick-
ness 0,25mm) as follows; for flavonoids, TLC was devel-
oped in n-butanol/acetic acid/water 4:1:5 (top layer), spots
were visualized with 1% aluminium chloride solution in
methanol under UV (366nm; Harborne, 1974). Coumarins
cence which becomes intense after spraying 10% potassium
hydroxide solution in ethanol. Steroids were identified with
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S. Kilani et al. / Environmental Toxicology and Pharmacology 20 (2005) 478–484
sprayed plates for 10min at 100◦C. The test for tannins was
carried out with FeCl3. Each class of tannins gave a specific
2.6. S9 fraction
The S9 microsome fraction is prepared from rats treated
with Aroclor 1254 (Maron and Ames, 1983). The compo-
nents of S9 mix were 0.4M MgCl2, 1.65M KCl, 1M G6P,
at a concentration of 0.04ml/ml of mix. The S9 fraction was
stored at −80◦C.
2.7. Salmonella-microsome assay
performed as described by Maron and Ames (1983). The
experiments were performed with and without an exogenous
metabolic system, the S9 fraction in S9 mix. One hundred
microliters of an overnight culture of bacteria (cultivated for
16h at 37◦C, approximate cell density (2–5)×108cells/ml)
and 500?l of sodium phosphate buffer (0.2M, pH 7.4 for
assay without S9) or 500?l of S9 mix were added to 2ml
aliquots of top Agar (supplemented with 0.5mM l-histidine
each extract.
The resulting complete mixture was poured on minimal
The plates were incubated at 37◦C for 48h and the revertant
bacterial colonies of each plate were counted. Negative and
positive control cultures gave numbers of revertants per plate
extract was considered mutagenic if the number of revertants
tripled in TA1535, over the spontaneous revertant frequency
(Maron and Ames, 1983; Marques et al., 2003).
Data were collected with a mean±standard deviation of
three plates (n=3).
2.8. Antimutagenicity testing
A modified plate incorporation procedure (Lee et al.,
2000) was employed to determine the effect of all isolates
on AFB1 and sodium azide induced mutagenicity. In brief,
and 0.5ml of phosphate buffer for direct mutagen sodium
of test compound) and 0.1ml of bacterial culture (prepared
as described in mutagenicity test) were added. After vortex-
ing gently and preincubating at 45◦C for 30min, 2ml of
top agar supplemented with 0.05M l-histidine and d-biotine
were added to each tube and vortexed for 3s. The resulting
on each plate were counted. The inhibition rate of muta-
genicity (%) was calculated relative to those in the control
group with the mutagen by the following formula: inhibition
rate (%)=[1−(number of revertants on test plates/number
of revertants on control plates)]×100. Each dose was tested
in triplicate.
2.9. Radical scavenging activity
Free radical scavenging activity of C. rotundus extracts,
was determined using the 1,1-diphenyl-2-picrylhydrazil
(DPPH) method (Ohinishi et al., 1994). The molecule DPPH
characterized as stable-free radical by virtue of the delocal-
ization of the spare electron over the molecule; this delocal-
ization gives rise to a deep violet color, characterized by an
absorption band in ethanol or methanol solution centered at
about 520nm. When a solution of DPPH is mixed with that
of a substance, that can donate a hydrogen atom, this gives
rise to the reduced form (diphenylpicrylhydrazine), with the
loss of violet color.
An aliquot (0.5ml) of ethanol solution containing differ-
ent amounts of C. rotundus extracts was added to 3ml of
daily prepared ethanol DPPH solution (0.1mM); the maxi-
mum concentration of the extract employed was 100?g/ml.
The optical density change at 517nm was measured 30min
later by a spectrophotometer.
The antioxidant assay was carried in triplicate and the
readings were averaged.
The scavenging activity was measured as the decrease in
absorbance of the samples versus DPPH standard solution.
Results were expressed as "percentage inhibition" (%) of the
by the formula:
(%) =
?(ODcontrol− ODsample)
× 100
where ODcontrolis the initial absorbance and ODsamplethe
value for added sample concentration (Lee et al., 2003).
IC50parameter is defined as the concentration (?g/ml)
of substrate that causes 50% loss of DPPH activity (color)
and it was calculated by using the Litchfield and Wilcoxon
3. Results
3.1. Phytochemical study
The results of our assay on the crude extract and
fractions are shown in Table 1. The aqueous, TOF and
methanol extracts showed the presence of various quantities
of flavonoids, coumarins and tannins. Ethyl acetate extract
showed the presence of sterols and flavonoids.
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S. Kilani et al. / Environmental Toxicology and Pharmacology 20 (2005) 478–484
Table 1
Phytochemical screening of extracts from aerial parts of Cyperus rotundus
Extracts Yield (%, w/w)TanninsFlavonoidsCoumarins Sterols
Aqueous extract
TOF extract
Ethyl acetate extract
Methanol extract
−: not detectable; +: low quantities; ++: high quantities, ++++: very high quantities.
3.2. Genotoxic activity of extracts
In a series of experiments preceding the antimutagenic-
ity studies, it was ascertained that the different amounts of
extracts added to the indicator bacteria does not influence
their viability, and mutation frequencies does not change
significantly when compared to spontaneous mutation fre-
activation are reported in Table 2.
No one of the tested extracts induced significant increase
of the revertants number in TA98, TA100, TA1535 and
TA1538 strains, as well as with or without S9 metabolic sys-
3.3. Antimutagenicity assay
Doses of 10?g/plate of AFB1, 1.5?g/plate of sodium
azide were chosen for the antimutagenicity studies, since
these doses were not toxic and induced 319±17 (AFB1),
and 427±0 (sodium azide) revertants in S. thyphimurium
TA100. AFB1 at the concentration of 10?g/plate induced
238±10 revertants in TA98 strain, and sodium azide at the
concentration 1.5?g/plate induced 495±32 revertants in
rotundus on the mutagenicity of positive mutagens using the
plate incorporation assay is illustrated in Tables 3 and 4. The
addition of aqueous extract reduced AFB1 induced muta-
genecity and a clear dose–response effect was noticed. At
the concentrations of 50, 200 and 500?g/plate, the aqueous
extract reduced the AFB1 induced mutagenecity by respec-
tively 25.12, 35.82 and 46.76% with S. thyphimurium TA98
strain, and respectively 35.05, 41.49 and 42% with TA100
strain. Whereas, TOF, ethyl acetate and methanol extracts
were highly effective in reducing the mutagenicity caused by
the indirect mutagen AFB1, with respectively 88.65, 84 and
82.73% at a dose of 500?g/plate in the TA100 assay sys-
tem and respectively 62.43, 72.88 and 74.62% at a dose of
500?g/plate in the TA98 assay system.
Ethyl acetate and methanol extracts showed almost
the same antimutagenic activity towards sodium azide
in TA100 assay system (respectively 74.22 and 68.32%
at 500?g/plate), but the highest antimutagenic activ-
ity was observed at the dose 50?g/plate with methanol
extract (88.5%). Ethyl acetate extract has dose indepen-
dent inhibitory effect. These two extracts showed a lower
antimutagenic activity towards the directly acting mutagen,
sodium azide, in the TA1535 assay system (with respectively
39 and 49.5% inhibitory at 500?g/plate) when compared
to the TA100 assay system. Likewise, TOF and aqueous
extracts exhibited weak inhibition activity against sodium
azide induced mutagenicity in the TA1535 assay system.
The highest inhibition rate obtained with TOF and aqueous
Table 2
Mutagenic effect of different extracts from Cyperus rotundus in S. typhimurium TA98, TA100, TA1535 and TA1538 assay systems in the presence and absence
of exogenous metabolic activation system (S9)
ExtractsDose (?g/plate) His+ revertants/plate
13.6 ± 2.5
16± 3
21± 3
9.5 ± 3.5
17± 2
16.5 ± 1.5
14± 0
18± 1
20± 1
16± 1
18± 1
22.5 ± 1.5
16± 4
269± 20
111± 15
116± 10
120± 5
101± 10
128± 10
130± 4
104± 3
107± 1
105± 2
109± 3
114± 0
111± 1
106± 1
427± 0
Aqueous extract50
15± 2
16± 2
28± 3
14± 4
16.5 ± 2.5
18.5 ± 0.5
10± 0
11.5 ± 0.5
15± 1
10± 3
9± 1
14± 1
22± 4
238± 10
12± 3
12± 1
16.5 ± 1.5
11.6 ± 2
14.5 ± 1.5
17± 3
10± 4
11± 2
13± 1
11.5 ± 0.5
13± 0
14± 1
12.5 ± 2.5
495± 32
15± 2
16± 1
21± 4
20± 4
17± 1
25± 4
10± 2
12± 1
11.5 ± 0.5
9.5 ± 1.5
9± 2
12± 1
18.5 ± 6.5
97± 13
10± 4
11± 1
12.5 ± 0.5
5.5 ± 1.5
6± 1
9± 1
10± 2
11 ± 0.5
12± 3
13± 4
13± 1
14± 1
11± 4
519± 0
8.5 ± 0.5
11± 1
16.5 ± 2.5
9± 1
10± 3
10.5 ± 2.5
10± 1
13± 2
14± 1
12± 6
13± 5
12.5 ± 0.5
15.5 ± 2.5
204± 5
TOF extract
Ethyle acetate extract
Methanol extract
Spontaneous revertants
Positive control (PC): TA100/−S9 and TA1535/−S9, SA (1.5?g/plate); TA100/+S9 and TA98/+S9, AFB1 (10?g/plate); TA98/−S9, 2-NF (1.5?g/plate);
TA1538/+S9/−S9, 2-NF (5?g/plate); TA1535/+S9, 2-AA (1?g/plate).
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S. Kilani et al. / Environmental Toxicology and Pharmacology 20 (2005) 478–484
Table 3
Effect of aqueous extract, TOF, ethyl acetate and methanol extracts on the mutagenicity induced by Aflatoxin B1 (10?g/plate) in Salmonella thyphimurium
TA100 and TA98 assay systems in the presence of S9
ExtractsDose (?g/plate)TA98TA100
Nb revertants/plate %inhibition of mutagenesis Nb revertants/plate%inhibition of mutagenesis
Aqueous extract
–37± 1
238± 10
187.5 ± 0.5
166± 4
144± 5
138.5 ± 1.5
129.5 ± 17
112.5 ± 2.5
106.5 ± 11.5
103.5 ± 3.5
91.5 ± 4.5
114± 11
88.5 ± 11
88± 10
TOF extract
Ethyl acetate extract
Methanol extract
Nb: number of revertants/plate±S.D.
Table 4
Effect of aqueous extract, TOF, ethyl acetate and methanol extracts on the mutagenicity induced by sodium azide (1.5?g/plate) in Salmonella thyphimurium
TA100 and TA1535 assay systems in the absence of S9
Extracts Dose (?g/plate) TA1535 TA100
Nb revertants/plate %inhibition of mutagenesisNb revertants/plate %inhibition of mutagenesis
Aqueous extract
TOF extract
Ethyl acetate extract
Methanol extract
Nb: Number of revertants/plate±S.D.
extracts was respectively 17.5 and 26%, when 50?g/plate
were added to the TA1535 assay system, and 20 and 31%
respectively, when 50?g/plate were added to the TA100
assay system. Antimutagenic effect of TOF and aqueous
extracts against sodium azide was very weak, when a large
excess of each extract was added to the assay system (inhibi-
tion rate was respectively 12 and 4.3% at 500?g/plate with
3.4. Radical scavenging activity on DPPH
The antioxidant activity of C. rotundus extracts was eval-
uated by their abilities to, scavenge DPPH free radicals, and
inhibit the formation of lipid peroxides. The radical scav-
enging activity of the compounds can be measured as a
Fig. 1. Scavenging effects of different extracts from Cyperus rotundus
against the radical DPPH.
Page 6
S. Kilani et al. / Environmental Toxicology and Pharmacology 20 (2005) 478–484
decolorizing effect following the trapping of the unpaired
electron of DPPH.
of DPPH standard solution of respectively 63, 74.5 and
85.36%, at a concentration of 100?g/ml, and IC50 val-
ues of 15, 14 and 20?g/ml (Fig. 1). Whereas, aqueous
extract showed a weak antioxidant activity compared to ?-
DPPH standard solution was of 26.48% at a concentration of
4. Discussion
rotundus in all Salmonella tested strains indicates that DNA
does not seem to be a relevant target for these extracts.
The absence of mutagenicity observed with polar and less
polar extracts could be related to the presence of epoxide
derivatives. It is not a characteristic of all natural products
in use, since other medicinal plants assayed with the Ames
test, in the presence or not of the S9 mix, have resulted posi-
tive for mutagenicity (Hyun et al., 1987; Sohni et al., 1995).
Results obtained with TA98, TA100, TA1535 and TA1538
strains, showed that the four tested extracts obtained from
aerial parts of C. rotundus even at high concentration, did
not induce increase in number of revertants when compared
to the number of spontaneous revertants. Nevertheless, some
dilutions showed a statistically significant decrease in num-
ber of revertants when compared to spontaneous revertants,
reflecting a toxic effect. In fact, TOF and methanol extracts
were slightly toxic to respectively TA98 and TA1538 bacte-
could be indicative of the presence of hormesis.
The promising antimutagenic, antioxidant activities and
absence of mutagenicity of the different extracts from C.
rotundus, thus suggest that these extracts may contain phy-
topharmaceutical molecules of interest. Other biological
properties should be studied to evaluate their pharmacolog-
ical potentials and to understand the mechanisms by which
these extracts acts.
Antimutagenic properties elicited by plant species have a
full range of prospective applications in human healthcare.
Herbal remedies and phytotherapy drugs containing active
principles are currently developed to protect against elec-
trophile (e.g. free radical) attack to DNA and its widespread
outcomes such as ageing and cancer. Even for populations
which use herbs traditionally, encouraging the use of species
with chemopreventive actions could be helpful as part of life
expectancy improvement strategies: costs are significantly
low, herbs have usually little or no toxicity during long-term
oral administration and are available at large scale.
The preliminary chemical study of the tested extracts
of C. rotundus, revealed the presence of important quan-
tities of flavonoids, tannins and coumarins in TOF and
methanol extracts. Ethyl acetate extract showed the presence
of sterols and flavonoids. These results could be correlated
to the mutagenic inhibitory effect observed with the same
extracts on AFB1 induced mutagenicity. In fact, flavonoids
nins (Schimmer and Lindenbaum, 1995) are known to have
antimutagenic effect. In the Ames test, TOF, ethyl acetate
and methanol extracts from aerial parts of C. rotundus inhib-
ited strongly AFB1 mutagenicity compared to the results
obtained against sodium azide induced mutagenicity test,
suggesting that these extracts necessitated metabolic activa-
tion. The weak antimutagenic activity of TOF and aqueous
extracts when large excess of each one was added, could be
explained by inhibition of the penetration through the cell
membrane at high doses, of extracts or molecules witch are
implied in the mutagenic inhibitory effect towards sodium
that these two extracts may prevent the metabolic activation
of AFB1, or they may directly protect DNA strands from the
electrophilic metabolites of the mutagen.
On the other hand, ethyl acetate and methanol extracts
showed a weak antimutagenic activity towards the directly
to TA100 assay system. In fact, strain TA100 generally has a
higher sensitivity to mutagenic insult as compared to strain
TA1535 due to the enhancement of SOS mutagenesis facil-
itated by the mucAB genes on the plasmid pKM101 that is
can suppose in our case that strain TA100 is more sensitive
than strain TA1535 to the antimutagenic effect of the tested
Otherwise, the mutagen AFB1 undergoes an epoxidation
process by hepatic microsomal cytochrome P450 and suc-
cessive epoxide hydrolysis and glutathion conjugation. The
epoxide and other intermediates substitute for the nitrogens
of nucleic acid in DNA strands and cleave DNA strands to
cause mutagenicity. Moreover, several metabolic intermedi-
ates and reactive oxygen species (ROS) formed during the
process of microsomal enzyme activation are also capable of
breaking DNA strands. In contrast, sodium azide requires no
activation by hepatic microsomal enzymes, to damage DNA
exhibited significant antimutagenicity towards AFB1 as well
as sodium azide. This suggests that unidentified antimuta-
gen compounds are selective in their activity (Zani et al.,
1993). The same extracts exhibit the most important antiox-
idant activity towards the free radical DPPH. These results
were correlated with chemical composition of the extracts.
In fact, the chemical study of the tested extracts, revealed the
presence of important quantities of flavonoids in TOF, ethyl
acetate and methanol extracts, and polyphenols in TOF and
methanol extracts.
tion and exert these effects as antioxidants, free radical scav-
engers, and chelators of divalent cations (Shon et al., 2004).
Page 7
S. Kilani et al. / Environmental Toxicology and Pharmacology 20 (2005) 478–484
The results of our experiments confirm known antioxidant
activities of flavonoids (Vaya et al., 2003; Park et al., 2004)
dus extracts could give rise to anticarcinogenic agents and,
could be promising candidates for further studies designed
to obtain more evidence on their components with potential
chemo-preventive activity.
We thank Dr. Felzen (UERJ, Brazil) for providing the
strains of the Ames test.
Calomme, M., Pieters, L., Vlietinek, A., Berghe, D.V., 1996. Inhibition of
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1991. Contribution ` a l'´ etude de la pharmacop´ ee traditionnelle de
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Phytother. Res. 11, 392–394.


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Brighton Opening Day!!!
Brighton kicks off the Utah ski season in style. Nicely groomed runs, some park, some pow and good vibes!!!
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Yeti friend Jenny Block weighs the pros and cons of learning to ski and how to gear up for the challenge.
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The Spa at Stein Eriksen Lodge is a must for anyone visiting Park City.
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Think winter is over? Think again. This is April in Utah. The deepest snow of the season and no crowds. Winter isn't over yet, come skiing in Utah! Many resorts open until the end of April, Snowbird will be open until Memorial Day. SkiUtah.com


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With over thirty years of experience with work in Brazil and abroad, Mozar Earth, composer, arranger and pianist, released her first CD of Composition Notebook. A gift for your audience, which has all the originality and his language distinctly Brazilian. Playing with consummate talented artists such as Milton Banana, Caetano Veloso and Lucio Alves, Brazil, moved to France where he would record two albums with drummer Nene, "Point of Musicians" and "Minuano", also followed the singer Joyce in his European tour, and playing in various jazz clubs of Paris.
He moved to Denmark where he was invited to workshops to promote the Danish Jazz Center, as well as in Rotterdams Conservatorium in the Netherlands. When you meet Edson Machado form the group "Edson Machado and Good News," who went to America on tour.
Back in Brazil, already well known and respected for his work, was invited to participate in various projects. Among them: Project Tom Brazil, where they recorded several CDs with big names such as Egberto Gismonte, Paulo Moura, Wagner Tiso, Raphael Rabello, among others; Crying High Project with Jim Hall, Oscar Castro-Neves and the Quartet composed by musicians Sizão Free Machado (bass), Teco Cardoso (woodwinds) and Tutty Moreno (drums).
Along with singer-songwriter Joyce and Free Quartet toured throughout Brazil, Europe and Japan Still Joyce, participated as a pianist and arranger in the recording of Song Books Ari Barroso, João Donato and Tom Jobim.
Participated in two consecutive years at the Festival of Campos do Jordao, sponsored by the Ministry of Culture of the State of São Paulo, responsible for Piano Master Class Brazilian People. Serves on several educational projects with his "Piano Rhythmic Brazilian", the Free University of Music Tom Jobim. He is currently touring the release of their CD.
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I grew up around Atlanta, GA and started playing piano when I was around 7 years old and bass when I was 11. Most of my education has been on the upright bass. I've studied classical bass performance at major music schools on the east coast and in the midwest. I've studied and worked with musicians from many of the great orchestras around the world.
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I grew up in the San Francisco Bay Area, where I started playing flute when I was 8 and bass when I was 13. In 2002, I moved to New York City to attend The Juilliard School, where I earned a Bachelor of Music degree in Double Bass performance. I came to Pittsburgh to attend Carnegie Mellon University, where I got a Master's of Music degree and a post-graduate Performance Residency Certificate. Since finishing at Carnegie Mellon in 2011, I have been freelancing in Western PA, Ohio, and West Virginia.
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Richard Littlejohn: Mayday, Mayday, Brown Hawk Down!
Here's one you may have missed over the weekend. Apparently, Gordon Brown was just 'minutes from death' on his recent visit to Afghanistan.
Shortly before his helicopter was about to take off, local police foiled a plot to blow it out of the air.
Two 'hostiles' with guns were spotted underneath the flight path.
Scroll down for more
While the Prime Minister was ushered back to safety inside the Green Zone, the alleged gunmen are thought to have escaped.
The reason you may have missed it is because this was one of those Sunday newspaper 'exclusives' which remain exclusive, largely because they're not true.
If it really had been true, Gordon's brush with death would have been front-page news all round.
But it wasn't, so it bit the dust. Everybody back on the coach - or, in this case, helicopter.
More from Richard Littlejohn for The Daily Mail...
- The Left hate everyone - not just the white working class, says RICHARD LITTLEJOHN 24/11/14
- RICHARD LITTLEJOHN: Warped values, zealots and a school that's 'too English' 21/11/14
- RICHARD LITTLEJOHN: Welcome to the Hotel Intifada 18/11/14
- RICHARD LITTLEJOHN: If teachers must strike, make 'em pay 14/11/14
- RICHARD LITTLEJOHN: Twiplets? Two dads and a twio of mums - This is about what's good for the adults, not for the children 11/11/14
- The proof we live in two Britains: RICHARD LITTLEJOHN on the magnificent millions paying silent tribute at the Tower of London - while selfish anarchists bring chaos to the heart of the capital 06/11/14
- RICHARD LITTLEJOHN: As a singer is accused of 'racism' for wearing a Red Indian fancy dress... Next these idiots will stop children playing Cowboys and Indians 06/11/14
- RICHARD LITTLEJOHN: Why the hell are we importing beggars? 04/11/14
- RICHARD LITTLEJOHN: Don't weep for these so-called British jihadis 31/10/14
Having leaked this Brown Hawk Down fairytale in a desperate attempt to divert attention from Alistair Darling's admission that Britain was facing the worst financial crisis since Henry VIII devalued the groat in 1526, Downing Street was quoted as saying it never comments on security matters.
How convenient.
This was just another clumsy, cynical insult to our intelligence to add to Jolly Jack Straw's barefaced lies about how the whole Cabinet is united and foursquare behind the Prime Minister.
Somewhere in the bunker, some bright spark thought that if they could persuade us that Gordon had narrowly escaped being assassinated, it would take our minds off the implosion of the Government and the gathering economic tsunami.
Even if it had succeeded, the respite would have been short-lived. Along came Jacqui Smith's memo about the devastating effects of the credit crunch on home affairs.
This warrants further examination, as it offers a telling insight into the New Labour mindset.
Ask most people what worries them about the economic downturn and they'll tell you they're concerned about losing their job, paying the mortgage, sky-high taxes, rising food and fuel costs and having to cut back on luxuries like holidays.
Not Jackboot Jacqui.
Uppermost in her mind is the potential for far-Right extremism, increased racism and further radicalisation of Muslims.
She also frets that there'll be more burglaries, violence and smuggling, with dwindling numbers of police on the streets to deal with it all.
And she thinks there will be more illegal immigration because people won't be able to afford the price of a visa.
This is the Looking Glass world these people inhabit. They can't think outside their own narrow obsessions.
If she really was worried about radical Islam, she'd tear up the yuman rites act and kick out the kind of preachers of hate featured on last night's Undercover Mosque sequel on Channel 4.
Most burglaries are committed to buy drugs, not to pay mortgage arrears.
As for increased violence, I don't believe that anyone embarks on a stabbing spree because their gas bill has gone through the roof.
There's one overwhelming reason why there's a good living to be made smuggling booze and cigarettes - and that's because, thanks to this Government, taxes in Britain are way higher than those in Europe.
And the credit crunch isn't responsible for the lack of police on the streets, either - she is.
We've got more coppers than ever before, but most of them spend their time filling in forms, suing each other for discrimination and chasing 'hate crimes'.
This is a direct result of policies imposed on the Old Bill by the Guardianistas in the Home Office.
Illegal immigrants come here because they know we're a soft touch and they'll never get sent back, not because they can't afford 500 quid for a visa.
The truth is that this Government is a busted flush, bereft of ideas, fatally wounded by incompetence, dishonesty, disloyalty and hubris.
Labour's only solution to everything is more of the same, more public spending, more state interference - hence Gordon's brilliant plan for solving the repossessions crisis by turning the whole of Britain into a giant council estate.
He's going to pay for it by cutting back the Navy because he thinks that terrorism is the only serious security threat Britain faces.
So we can forget Russia, can we? Remember, as the pound plummets through the floor on the foreign exchange markets, that this is the same genius who - when he was at the Treasury - stared into his crystal ball, decided we didn't need our gold reserves any more and sold them off at car-boot sale prices.
In the past year, Gordon's had more relaunches than the Apollo space programme. All have gone up in flames before the booster rockets have kicked in.
With even former loyalists like Jackboot Jacqui and his Glove Puppet at Number 11 running round squealing 'We're All Doomed', this latest re-re-re-re-relaunch has been aborted before it gets off the ground.
Fictitious gunmen in Afghanistan aside, it's the 'hostiles' in his own Cabinet Gordon should be worried about.
Minutes from death? Politically, he's dead already.
Never mind the planet, save the Land Rover
Land Rover is cutting back production, going on to a four-day week and suspending the night shift until the end of the year.
The credit crunch is being blamed, but you can also throw in the Government's soaring taxes on fuel and so-called 'gas guzzlers'.
Then there's the general hostility towards 4x4s, especially Range Rovers, which are blamed for everything from melting the ice caps to poisoning bay-bees in their pushchairs.
While self-righteous eco-warriors are vandalising Discoverys and ministers pile punitive taxes on owners in the name of saving the planet, no one stops to consider the economic consequences.
It may belong to the Indian firm, Tata, these days, but Land Rover is one of our few remaining world-class manufacturers.
Exports bring in vital foreign currency and keep 8,500 people employed directly, with at least the same number again working in dealerships and the supply chain.
Forcing every last Range Rover off the streets of Britain isn't going make the slightest bit of difference to 'global warming'.
And does anyone seriously believe that BMW, Mercedes, Audi and Toyota are going to stop making 4x4s?
But that won't stop the eco-loonies doing their worst to wreck a proud, profitable company and consign thousands of workers to the dole queue and their families to hardship - just so they can feel good about themselves.
Like all idealists, they profess to love the planet but really they hate people.
Met should sack this self-pitying chancer now
Had I called a press conference last Friday and proceeded to slag off the Editor of the Daily Mail in no uncertain terms, I think it would be fair to assume that this column wouldn't be appearing today.
Yet Tarique Ghaffur remains behind his desk at Scotland Yard despite tipping a bucket-load over his boss, Ian Blair.
Britain's most senior Asian policeman has decided to go public, even though his ludicrous claim for racial discrimination is pending before a tribunal.
Blair's deputy, Paul Stephenson, says it's time for Ghaffur to shut up. Sorry, it's gone beyond that.
Blair should sack this greedy, self-pitying ingrate immediately.
What has the Met got to lose? They're already staring down the barrel of a vexatious, opportunist compensay-shun claim. Let him throw in unfair dismissal, too, while he's at it.
Ghaffur clearly doesn't want to be there. He's angling for gardening leave.
The Yard should kick him out without a penny and then defend the case rigorously.
Don't forget, this is our money, which would be better spent putting bobbies on the beat - not lining the pockets of lawyers and topping up the retirement funds of chancers like Ghaffur.
He's even trying to up the ante by claiming that he is having to hire bodyguards because of 'threats' made against him.
Who does he think he is - Salman Rushdie?
Ghaffur says he 'fears for his safety'. It's not his safety in question, it's his sanity.
More absurd elf'n'safety laws
The cost of home repairs is soaring because elf'n'safety is forcing contractors to hire scaffolding instead of using ladders for even the most minor job.
Guidelines state: 'When working from a ladder, three points of contact should be maintained.
'That means both feet and one hand in contact with the ladder or stepladder. Do not work off the top three rungs - they provide a handhold.'
Have these imbeciles ever been anywhere near a building site?
If both feet and one hand have to be in contact with the ladder, how the hell can anyone even hammer a nail into a wall?
The same rules apply to window cleaners, who are now reduced to cleaning upstairs panes with hosepipes.
I can only think of one good reason for erecting a scaffold - and that's to string up whoever came up with these absurd laws.
Here come the polar bearskins
Buckingham Palace guardsmen may soon have to dispense with their bearskins after complaints from animal rights activists.
They could be replaced with alternative designs from Vivienne Westwood and Stella McCartney.
In what sane society does the Army consult Looby Loo dress designers over what constitutes acceptable uniforms?
Why not call in Trinny and Tranny and have the Guards standing to attention in bare skins?
Activists say the numbers of black bears used to make the traditional headgear are dwindling.
In which case, make them out of polar bear fur. There's more of them than ever before.
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Photo Gallery
Yahoo seeks to shake up search, Web browsing
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This image provided by Yahoo shows the company's "Axis" app for iPad. The tool, also available for iPhone and iPod Touch, alters browsers made by other companies so search results can be displayed in a more convenient and compelling format. (AP Photo/Yahoo)
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Rugby Union
Select a team
Six Nations
- England
- France
- Ireland
- Italy
- Scotland
- Wales
Aviva Premiership
- Bath
- Exeter
- Gloucester
- Harlequins
- Leicester
- London Irish
- London Welsh
- Newcastle
- Northampton
- Sale
- Saracens
- Wasps
The Rugby Championship
- Australia
- New Zealand
- South Africa
Guinness PRO12
- Cardiff Blues
- Connacht
- Dragons
- Edinburgh
- Glasgow
- Leinster
- Munster
- Ospreys
- Scarlets
- Treviso
- Ulster
- Zebre
Top 14
- Bayonne
- Bordeaux-Begles
- Brive
- Castres
- Clermont Auvergne
- Lyon
- Montpellier
- Racing Metro
- Stade Francais
- Toulon
- Toulouse
- Grenoble
- La Rochelle
- Oyonnax
|Home team
|Away Team
Cardiff Blues
|29 - 20
Match Links
- European Rugby Champions Cup
- Pool 2
- 6th Dec 2013
- Ground: Cardiff Arms Park
- Att: 6,144
Heineken Cup Pool 2: Phil Davies delighted with Blues win
Related links
- Cockerill wary of Montpellier
- Keatley calls for Cup focus
- Rees: We're out of it now
- Mallinder 'embarrassed'
- Easter: Quins back on track
- McCall delighted with Sarries
- Easterby finds some positives
- Davies lauds May after try
- Lam: Connacht belief the key
- Blues v Warriors: Teams
- Northampton v Leinster: Teams
- Ulster v Treviso: Teams
- Munster v Perpignan: Teams
- Clermont v Scarlets: Teams
- Leicester v Montpellier: Teams
- Zebre v Saracens: Teams
- Toulouse v Connacht: Teams
- Edinburgh v Gloucester: Teams
- Castres edge past Ospreys
- Late bonus for Clermont
- Ulster crush Treviso
- Toulouse stunned by Connacht
- Leicester down Montpellier
- Gloucester beat Edinburgh
- Munster maul poor Perpignan
- Saints hit for six by Leinster
- Blues win Heineken thriller
Also see
Cardiff Blues head coach Phil Davies was understandably jubilant at his team's 29-20 Heineken Cup victory over Glasgow at the Arms Park, which took them to the top of Pool 2.
Davies believes his team have started to show the form he knew they were capable of during recent struggles.
He said: "After all the painful times we've had over the last 18 months, we're making progress.
"We're trying to build a style of playing here whoever is available and it's coming along.
"And to play with the desire we did in the second half, even if it was bit scruffy, kept us in the group."
The former Wales forward had special praise for young skipper Sam Hobbs.
"The way he led the side was magnificent," he said. "A lot of our youngsters did tremendously."
Now the Blues have to repeat the job next Friday at Scotstoun. "Glasgow are a top side and they'll be champing at the bit," added Davies. "We've got to be ready for that. We're going to have to do what we did tonight and then some more."
His Warriors opposite number, Gregor Townsend, admitted: "Cardiff showed what a good team they are and they also showed how much they wanted it. We've got to do that next week - and more.
"I thought we played pretty well for the first 15 minutes, but couldn't get points on the board. Then they got their tails up, but we still had the belief to play better in the second half.
"In the first half we didn't work hard enough in attack. You have to go through the phases and we were trying to go too soon. We couldn't get much momentum in the set-pieces and that makes it difficult to get your game going.
"We simply need to produce a better performance next week."
Sky Bet Odds:Click Here for Your Free Bet
|European Rugby Champions Cup
|Friday 5th December
|European Rugby Champions Cup
|Montpellier vs Bath
|Saturday 6th December
|Sale vs Saracens
|Munster vs Clermont Auvergne
|Ulster vs Scarlets
|Benetton Treviso vs Northampton
|Ospreys vs Racing Metro 92
|Sunday 7th December
|Castres vs Wasps
|Harlequins vs Leinster
|Leicester vs Toulon
|Toulouse vs Glasgow
|Friday 12th December
|Bath vs Montpellier
|Saturday 13th December
|Saracens vs Sale
|Leinster vs Harlequins
|Toulon vs Leicester
|Glasgow vs Toulouse
|Northampton vs Benetton Treviso
|Racing Metro 92 vs Ospreys
|Sunday 14th December
|Clermont Auvergne vs Munster
|Wasps vs Castres
|Scarlets vs Ulster
|Saturday 17th January
|Saracens vs Munster
|Sale vs Clermont Auvergne
|Harlequins vs Wasps
|Leinster vs Castres
|Leicester vs Scarlets
|European Rugby Champions Cup
|Sunday 26th October
|European Rugby Champions Cup
|Benetton Treviso 10 - 26 Racing Metro 92
|Wasps 16 - 23 Harlequins
|Clermont Auvergne 35 - 3 Sale Sharks
|Castres 16 - 21 Leinster
|Saturday 25th October
|Scarlets 15 - 3 Leicester
|Northampton 34 - 6 Ospreys
|Montpellier 13 - 15 Glasgow
|Bath 19 - 21 Toulouse
|Ulster 13 - 23 Toulon
|Friday 24th October
|Munster 14 - 3 Saracens
|Sunday 19th October
|Leinster 25 - 20 Wasps
|Toulon 28 - 18 Scarlets
|Ospreys 42 - 7 Benetton Treviso
|Toulouse 30 - 23 Montpellier
|Saturday 18th October
|Leicester 25 - 18 Ulster
|Racing Metro 92 20 - 11 Northampton
|Saracens 30 - 23 Clermont Auvergne
|Glasgow 37 - 10 Bath
|Sale Sharks 26 - 27 Munster
|Friday 17th October
|Harlequins 25 - 9 Castres
Experts & Blogs
Phil Edwards
Read the thoughts and opinions of Phil Edwards with skysports.com


text:
Arts & Entertainment
Film academy debuts original online short films
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California Chrome to run in Belmont, nasal strips and all
There was concern the winner of the Kentucky Derby and the Preakness would not be allowed to wear nasal strips at the June 7 Belmont Stakes, the third leg of thoroughbred racing's Triple Crown.
'Godfather,' Woody Allen cinematographer Gordon Willis dies
He shot the first two "Godfather" movies and eight films with Woody Allen. Watch clips from his most famous films here and learn why he was called "The Prince of Darkness."
Jackson, Timberlake own Billboard Music Awards (winners list)
Prince of pop Justin Timberlake ruled the Billboard Music Awards along with his idol, Michael Jackson, who appeared via hologram. See the list of winners.
Unity is a difficult mission for Christians in Israel
In Israel, Christians make up just 2 percent of the population. Their numbers are rising with a steady surge of African and Filipino migrants, but a shared faith isn't bringing them together.
SoCal's California Chrome wins Preakness, could take Triple Crown
Southern California's own California Chrome finished first at the Preakness Stakes on Saturday, setting up the possibility of the horse winning the Triple Crown.
LA Kings, Blackhawks set for Western Conference final
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Southern Baptist leaders seek softer approach to homosexuality
Though the denomination still considers homosexuality a sin, some Southern Baptist Convention leaders are telling pastors to rein in harsh rhetoric and accept that gay people are in their pews.
5 fads that faded away: Hair lizards, indoor baseball and more
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New 'Guardians of the Galaxy' teasers tease another teaser
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Billboard Awards can use Michael Jackson hologram
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EZTV: Channeling West Hollywood's artsy video history
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Phoenix, The Strokes coming to Los Angeles for FYF Fest
Other bands slated to play at the two-day event include Haim, Interpol Caribou, Tycho, Blood Orange and Jamie XX.
#CapForStrat: The Avengers give a real dying man his last wish
The Avengers are teaming up to fight a formidable foe: Cancer. At least, one man's cancer, through the power of Marvel actors' selfies.
'Chef': Jon Favreau and Roy Choi on making a film about cooking and life
Filmmaker Favreau and chef Roy Choi talked with Take Two's Alex Cohen about collaborating on a movie that captures the essence of being a chef.
Is it socially acceptable to swear at your workplace?
Psychologists say cursing can make us feel stronger and more resilient. But when and where is it really OK to swear?


text:
Narrow your search
Several documentaries competing in the upcoming Sundance Film Festival pan in on tech's darker sides.
The MPAA has launched a helpful site that shows you where you can legally stream, rent, purchase and otherwise watch what it is you want.
The dark-comedy series gives Amazon its best shot so far at beating Netflix at the critical-accolades game, and in a new turn, all episodes go up at once September 26.
The Steve Jobs film biopic jOBS is set to debut later this week at the Sundance Film Festival, and will open in the US on 19 April.
Australian horror film "The Babadook" throws horror conventions out the window -- and scoops up the accolades as it goes.
By keeping current 4K content offerings proprietary, Sony and Samsung could hamper 4K adoption. Here's why.
The Steve Jobs biographical movie starring Ashton Kutcher will premiere at the Sundance Film Festival in late January.
This desktop staple has long been available for iPad, but now iPhone users can turn clips into polished movies with ease.
Chris Barrett, who was first to take Google Glass into a casino and also said he was first to film an arrest with Glass, finds he gets too many headaches. He's also lost his enthusiasm for the gadget.
The latest batch includes hour-long dramas for the first time, and Amazon Studios will again crowdsource content decisions, picking the ones to make full series based on customer viewing data and reviews.


text:
A signal analyzer to characterize the RF signal transmitted by a frequency hopping radio transmitter. The transmitted signal is analyzed while hopping across a broad frequency band without knowledge of the hop frequencies, timing or signal bandwidth. A wide range of signal parameters are measured on the dehopped signal to characterize the radio performance and the compliance to the radio specifications.
1. A method of broadband radio frequency analysis comprising the steps of:
receiving a frequency hopping radio input signal for broadband analysis, said input signal having segments at different hopping frequencies and different hopping times,
for each segment,
determining from the input signal a hopping time of the segment,
processing the segment to determine a frequency of the segment, and
processing the segment to determine signal parameters,
where the signal processing includes signal demodulation to form a demodulated signal and where the signal processing includes measuring a symbol rate where the symbol rate is calculated by analysis of zero crossing times in the demodulated signal,
where time differences between zero crossings is calculated from zero crossing times,
where a TOT histogram is compiled of the time differences as delta TOTs,
where a symbol period estimate of a symbol period is formed from a center of mass of a first major peak in the TOT histogram,
where the symbol period is calculated by,
computing the modulo of the delta TOTs and the symbol period estimate,
unwrapping the modulo results about the symbol period estimate,
fitting a straight line to the unwrapped data,
using a slope of the straight line to refine the symbol period estimate thereby producing a final value for the symbol period.
2. The method of
The present invention relates to methods and apparatus for broadband frequency characterization of radio wave signals and particularly for broadband frequency characterization of frequency hopping radio wave signals.
Frequency hopping is a form of spread-spectrum signaling where, for short instances of time, relatively narrowband signals are transmitted as short bursts with the carrier frequency for each burst tuned to a different one of a set of carrier frequencies than the ones of the carrier frequencies used for the previous burst and the next burst. The sequence of frequencies that is used for a sequence of bursts is known as the hopping sequence. The carrier frequency transmission at any particular instant of time for one burst is therefore different than the carrier frequency transmission at the previous instant of time for the previous burst and similarly is different than the carrier frequency transmission at the next instant of time for the next burst. While the bandwidth for any particular burst may be narrow, the bandwidth for the whole set of frequencies in the hopping sequence can be very large. Typically a frequency hop system hops over a bandwidth many times the bandwidth of the individual hop signal bandwidth. Bluetooth for example has a 1 MHz signal bandwidth and hops over 80 MHz. Some military radios have 25 kHz signal bandwidth with thousands of hop frequencies covering over 50 MHz. The frequency hoppers in use today hop over at least 8 times the bandwidth of the signal bandwidth.
Frequency hopping systems with changing frequency transmissions have a number of advantages over the fixed frequency transmissions of non-hopping systems. If a particular hop frequency, in the set of frequencies used in a hopping sequence, happens to include a frequency that is regularly occupied by another interfering radio signal, the frequency hopping system detects the occupied status and functions to retransmit the burst of data at a different frequency. Also, the frequency hopping system detects the regularly occupied frequencies for any particular installation and reestablishes a hopping sequence that excludes the occupied frequency from the set of frequencies in the hopping sequence.
Frequency hopping systems are more secure than fixed frequency systems because the interception of frequency hopped signals is significantly more difficult than interception of fixed frequency signals, particularly when the hopping sequence is not known in advance. If a communication protocol is intended to be secure, such as in military and other secure environments, the hopping sequence and other protocol, specification and standards information is not published and is changed from time to time to support secure operation.
In any environment, the characterization of radios and radio wave signals for frequency hopped systems is difficult because they operate and function over broad bandwidths and because each burst at a particular frequency is of relatively short duration. The characterization of signals for frequency hopped systems is even more difficult when done in a secret environment where the protocol, specification, standards, hopping sequence and other characterizing information is not fully known in advance. A secret environment is common since manufacturers and users of frequency hopping systems often wish to maintain their protocols, specifications, standards and hopping sequences confidential and unpublished.
In order to avoid the difficulties of characterizing frequency hopped systems, some analysis systems require the test radio to be put in a �hop-in-place� mode where the carrier frequency is the same for all bursts, that is, the frequency does not hop. Such �hop-in-place� systems eliminate the burden of dehopping the signal so that the analysis is much easier. However, such systems do not fully test the parameters that relate to or are affected by hopping and hence cannot fully characterize frequency hopping radios. Examples of such �hop-in-place� systems are the Agilent 89441A system with the Bluetooth� module and the Aeroflex RCTS-001 Radio Test Set.
In order to avoid the difficulties of characterizing frequency hopped systems when frequencies actually hop, some analysis systems require that the next hop in a hopping sequence for the test radio be known in advance by the analysis system. When the next hop in a hopping sequence is known in advance, such systems synchronize the frequency hopping of the analysis system with the frequency hopping of the test radio. In order to know the next hop in a hopping sequence in advance, analysis systems use the tuning information present in the radio signal messages of the test radio to derive each next hop frequency in the hopping sequence. Therefore, the next hop frequency is known in the analysis system before the hop actually occurs. Using the information from the radio signal messages, the analysis system synchronizes with the radio signal. In this manner, the frequency of the analysis system's local oscillator (LO) follows the hopping sequence in advance and thus can be used to dehop the radio signal being analyzed. In order for such systems to work, analysis systems are built to fully implement the radio signal protocols, specifications and standards, including the hopping sequence, for each radio to be analyzed. Such systems are expensive to build because many different radio signal protocols and standards exist. Further, such systems can only be used by those having full access to the signal protocols and standards including the hopping sequences. For many radio systems, however, for security and other reasons, such information is often not widely available. Examples of analysis systems that employ prior knowledge of the hops in a hopping sequence are the Agilent E1852B and Tektronix CMU 200 systems and the Marconi system (see U.S. Pat. No. 6,195,383). These Agilent and Tektronix test systems are designed to test the frequency hopping Bluetooth networks. They have internal Bluetooth modules that allow the test systems to become part of the network. These internal modules produce the carrier frequency values as they communicate with the radio under test external to the test system.
Because the �hop-in-place� analysis systems provide limited information, they are not fully adequate for the communication industry. Because the �known-in-advance� analysis systems have cost disadvantages and do not perform well for analyzing radios that are not operating within the specification range for the protocols and standards, they are not fully adequate for the communication industry.
Accordingly, in order to meet the demands of the communication industry, improved methods and apparatus are needed for analyzing frequency hopping signals, and other broadband signals, when the hopping sequences and other signal protocols and standards are not relied upon prior to analysis.
The present invention is a method and apparatus for broadband radio frequency analysis. The analysis is performed by receiving an input signal from a device under test; determining the start and stop of segments of the signal; and for each segment, processing the segment to determine the frequency of the segment and processing the segment to determine signal parameters of the signal. Typically, the device under test is a frequency hopping radio and the segments are instances of the signal at hop frequencies of the radio.
The present system analyzes frequency hopped signals without requiring prior knowledge of the transmitter specifications and the protocols and standards used for messaging and otherwise used for controlling the radio communication. One of the advantages of the present system is that it is robust in analyzing radios that are not operating within their specifications. The capability of the present system to analyze unknown signals without need for knowledge of the radio specification is important in research and in the development of new radios. It is also useful for analyzing radios that are operating poorly.
Another advantage of present system is that it can be used to analyze unknown signals.
Another advantage of the present system is that it is able to analyze signals in the presence of interfering signals including other interfering signals of the same type.
The present system receives the input signal to be analyzed in a receiver. The receiver in one embodiment receives the input signal through a receiving antenna that receives a signal transmitted through the air interface by a radio. Alternatively, the receiver in another embodiment receives the input signal through a direct-wired connection to a wired-output of the radio thereby bypassing the air interface. In any case, the receiver signal is a radiofrequency signal. The radio input signal from the receiver is down converted, when necessary, and digitized to form a digitized signal. The digitized signal is processed and is determined to be active when energy at a sufficient level is present. When the processed signal is active, the analysis system determines the frequency and bandwidth of the processed signal. The frequency and bandwidth information is used to down convert, filter and decimate the processed signal to form a converted signal. The converted signal is demodulated and analyzed.
In the case of Bluetooth and many military radios, the demodulation consists of AM/ASK and FM/FSK demodulation. Signal parameters are measured on the demodulated signals.
The signal parameters include symbol rate, bit rate, hop duration, hop interval, signal amplitude, frequency offsets, rise/fall times and many others.
Symbols are generated from the demodulated signals. If specification information is known about the signal being analyzed, the bits can be generated from the symbols. For example, if the signal is an FSK signal as in Bluetooth, the frequency states are converted, when desired, directly to raw transmitted bits.
If the specifications of the transmitter are known, the measured parameters can be compared to the specifications to determine if the radio is operating properly in accord with its specification.
The foregoing and other objects, features and advantages of the invention will be apparent from the following detailed description in conjunction with the drawings.
The analysis performed in
A typical frequency hopping sequence that represents the input signal from the radio 1 that is to be analyzed is shown in
Another typical frequency hopping sequence that represents an input signal from radio 1, the device under test is shown in
If the input signal is transmitted at a low radio frequency, the RF/IF converter 5 is not necessary. For example, if the highest frequency of the input signal is 30 MHz, the received signal may be sampled directly with a sample rate of 60 Msamples/second or higher to obey the Nyquist criteria. Similarly, alias sampling can be used for signals near the sample rate. For example, if the input signal is from 110-125 MHz, the input signal can be sampled at 100 Msamples/second to create a digitized signal on the output of the A/D converter 6 of
The digitized signal on output 7 in
In parallel with AMPLITUDE component 24-1, the FREQUENCY component 24-2 determines the frequency of the input signal appearing on the output 7 from the front end unit 29 of
Various algorithms can be used to determine the frequency estimate at output 13. Spectral analysis using a Fast Fourier Transform, FFT, or similar algorithm, is a robust embodiment that uses substantial processing power and requires substantial time to execute. Spectral analysis is preferred when the transmitted signal is received via antennas as shown in
One preferred embodiment the frequency estimation block 11 uses the algorithm outlined in
Referring to
Referring to
When the max value in the 100 sample buffer memory 31 drops below the threshold determined in block 34, the signal estimator 46 is commanded at 37 to calculate the power spectrum on all samples in memory 36. This calculation is done via a windowed digital Fourier transform, DFT in block 38. One preferred embodiment uses a Hamming window; however, other windows also work well. If memory 36 contains N signals, an N point Hamming window is calculated and multiplied with the signal on a sample by sample basis. The N point DFT of the windowed signal is calculated. A subset of the output DFT bins is processed to determine the strongest signal. The subset is bins from 5 to N/2−5. The first few bins near DC do not contain signal energy of interest and are ignored. Samples from N/2 to N−1 are the complex conjugate of samples from 0 to N/2−1 and are ignored as their power spectrum is redundant. Samples from N/2−5 to N/2−1 are ignored because they contain no useful signal energy. If the signal band is known, just the bins associated with this band can be processed to save processing time and to ignore unwanted signals.
The DFT is used instead of an FFT algorithm so the present system can use all of the samples associated with the segment. The signal frequency accuracy is a function of the time duration of the samples in the DFT. Rounding the number of samples, N, to the nearest FFT size would exclude some samples reducing the measurement accuracy. Alternatively, the N samples can be padded with zeros to bring the buffer length to the nearest FFT size greater than N.
The power spectrum 40 of the bin subset is calculated by taking the magnitude squared 39 of the complex DFT output bins as shown in Eq 1. When the time samples in memory 36 have been processed, the memory is reset to start compiling the next segment.
The power spectrum bins at 40, P(n), are processed in block 47 to find the frequency at output 13 and bandwidth at output 17 of the strongest peak in the spectrum. The first step in block 50 is to find the bin number, nMAX, on output 51 and magnitude on output 52 of the strongest bin, PMAX, in P(n) input at 40. The bins below and above nMAX are examined in block 53 to identify all consecutive bins that have sufficient energy. This examination is done by finding all bins that exceed a threshold based on the PMAX. A typical threshold is to identify all bins exceeding X dB below the max bin. The first bin exceeding the threshold is nLOW and the last bin exceeding the threshold is nHIGH. A typical value of X is around 30 dB. Eq 2 shows the threshold calculation.
The bins associated with the strongest signal, nLOW through nHIGH, are processed to determine the signal frequency at output 13 and bandwidth at output 17. The signal frequency is estimated with a center of mass algorithm in block 54 as shown in Eq 3. The signal power is the value of the denominator of Eq 3.
The signal bandwidth, BW, 17 is calculated with Eq 4.
Alternatively, the bandwidth output at 17 can be calculated as bandwidth containing a given percentage of the total signal energy. The total signal energy is calculated by summing all bins about the peak bin, this would typically involve bins outside the bins from nLOW and nHIGH. For example, if the desired bandwidth value is to be that containing 98% of the signal energy, the bins below the peak bin will be summed to identify the bandwidth containing 49% of the total energy. Similarly, the bins above the peak bin are summed to identify the bandwidth containing 49% of the total energy. The upper and lower bandwidths are summed to produce the total bandwidth.
When the transmitter of radio 1 is wired to the present system as shown in
The down converter block 15 multiplies the digitized signal by a digital local oscillator to down convert the signal to baseband using Eq 5. The resultant digital signal at 18 is a complex signal.
The resultant signal at 18 will have one component around 0 Hz and an undesired component centered around −2 fc. The undesired component will be reduced to an acceptable level by lowpass filter 16. The filter 16 will also decimate the sample rate by M where only the M'th output filtered values are calculated by the filter 16. For example, in the case of Bluetooth, the hop frequency band covers 83.5 MHz. This band can be digitized with a 200 Msample/second sample rate. The individual hop channels are 1 MHz wide. It is reasonable to reduce the resultant complex sample rate of the baseband signal at 18 from 200 Msamples/second to around 1.25 M complex samples/second. In this case, the decimation factor M is 200/1.25=160. The low pass digital filter is either an FIR or IIR filter with bandwidth BW as determined at 17.
The baseband signal at 18 is processed to measure many of the signal parameters. The first step in the processing is to demodulate the data. The signal can be AM demodulated as shown in Eq 6, however, other algorithms can be used to generate the AM signal 20.
Other parameters may require the phase demodulated signal. The phase demodulated signal can be generated with Eq 7; however, other algorithms can be used to generate the phase demodulated signal at output 21.
Other parameters still may require the frequency demodulated signal at output 22. The frequency demodulated signal may be generated with Eq 8, however, other algorithms can be used to generate the FM signal.
Since the FM signal at 22 is derived from the derivative of the PM signal at 21, any high frequency noise in the PM signal at 21 will be magnified in the FM signal at 22. It is common to low pass filter the PM signal to reduce the high frequency noise. It is also common to low pass filter the AM signal at 20 and FM signal at 22 to allow more accurate measurements to be made. The mean value of the FM output at 22 can be used to refine the frequency estimate 13 to produce a more accurate reporting of the hop frequency.
The results of the present system are created in the signal analysis block 23. The AM signal 20 is used to calculate the rise time of the burst. This calculation is typically done by finding the average amplitude in the center 50% of the burst as a reference level and finding the time where the AM waveform at 20 is 10% and 90% of this reference amplitude. The rise time is the difference between the 90% and 10% times. Interpolation is used to measure the 10 and 90% times accurately. The 90% to 10% fall time at the end of the burst is similarly measured.
Some signals do not turn completely off between bursts; the AM waveform at 20 can be used to measure this amplitude. The amplitude of some signals can come up to a low level for a short period before the burst is judged to turn on, the AM waveform can be used to measure this amplitude and duration.
The AM waveform at 20 can also be used to measure the amplitude ripple magnitude and frequency across the duration of the burst.
If the signal is an AM or ASK signal, the AM waveform at 20 is used to determine the signal symbol rate, symbol rate drift, modulation depth, jitter, the symbols and other parameters.
If the signal is PSK, the PM waveform at 21 is used to measure the modulation−degrees per symbol state. For example a QPSK signal changes 90 degrees per symbol state. The PM waveform can be used to measure the signal symbol rate, symbol rate drift, modulation depth, jitter, phase accuracy, the symbols and other parameters.
If the signal is FSK, the FM waveform at 22 is used to measure the frequency deviation of the symbol states. The FM waveform is used to measure the signal symbol rate, symbol rate drift, modulation depth, jitter, phase accuracy, the symbols and other parameters.
The symbol rate is a key parameter to all digital signals. Various algorithms can be used to calculate the symbol rate including spectral analysis, correlation and time of transition (TOT) analysis. It is desired to calculate the bit rate independently on each signal segment. TOT analysis is selected as being the most accurate with the short amount of data available in the signal segment. The algorithm that follows is for an FSK signal, however, it is easily adapted for ASK and PSK signals.
The next step 64 is to remove the mean value of the FM samples. Next the times of each zero crossing 66, TOT, are calculated in block 65 by interpolating the time of the samples on either side of the zero crossing. The first difference at 83 of the TOTs are calculated in block 67: dTOT(k)=TOT(k)−TOT(k−1) for all TOTs in the burst.
A histogram of the dTOT values is compiled at 68 and analyzed to find the first major peak 81, bMAX in block 69.
The modulo of the dTOT values at 83 and the estimated symbol rate, τest, at 71 is calculated in block 72 to remove the double, triple, etc symbols from the dTOT values. An unwrap algorithm is used to correct for +/−τest errors as shown in the Matlab code of TABLE 2 below. This unwrap algorithm is used if the symbol rate estimate is in error enough so the mod(dTOT) values drift beyond τest.
The resultant mod_dTOT values are fitted to a straight line with a least squares fit 74. The resultant slope 75, m, is used 76 to produce the final symbol rate measurement 77 as shown in Eq 10.
The symbol rate is reported to the user. The symbol rate is also used to decode the individual symbol values and to determine the symbol rate jitter statistics. The first step in this process is to reconstruct the ideal waveform from the signal. A typical result is shown in
The raw digitized data at 7 are processed by the signal analyzer to determine the spurs, harmonics and unwanted signals in the signal band. This processing is accomplished by computing the spectrum of the signal and calculating the power and frequency of each signal exceeding a threshold. The threshold is usually x dB below the power level of the hop. The spurs and harmonics are calculated for each hop. The spur frequency is calculated by the center of mass algorithm presented in Eq 3 where nLOW and nHIGH are bin values about the bin identified as a spur. The spur power is the denominator of Eq 3.
While the invention has been particularly shown and described with reference to preferred embodiments thereof it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention.
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There is 1 private schools in zipcode 07474, NJ, serving 36 students.
Minority enrollment is 83% of the student body, which is more than the NJ state average of 28%.
The student:teacher ratio of 5:1 is lower than the state private school average of 10:1.
07474, New Jersey Private Schools
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WayneLakeview Learning Center
Po Box 4500
Wayne, NJ, 07474
(973)835-1777Special Education School36 students | Gr. 8-12
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