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Larvicidal activities and chemical composition of essential oils from Piper klotzschianum (Kunth) C. DC. (Piperaceae).

BACKGROUND
Volatile oils from fresh roots, stems, leaves and seeds of Piper klotzschianum (Piperaceae) were obtained by hydrodistillation and analysed by GC-FID and GC-MS. In total, 25 components, representing more than 95% of the examined oils, were identified. The essential oils were evaluated against Artemia salina Leach nauplii and fourth-instar Aedes aegypti larvae.


RESULTS
The major chemical constituents that were identified from various parts of this plant were 1-butyl-3,4-methylenedioxybenzene and 2,4,5-trimethoxy-1-propenylbenzene in the root, 1-butyl-3,4-methylenedioxybenzene in the stems and leaves and 1-butyl-3,4-methylenedioxybenzene, limonene and α-phellandrene in the seeds. The biological activities of these essential oils generally exhibited high toxicity against A. salina, with LC50 values that ranged from 7.06 to 15.43 µg mL(-1), and significant larvicidal activity against fourth-instar A. aegypti larvae was observed in the essential oils from the seeds (LC50 of 13.27 µg mL(-1)) and roots (LC50 of 10.0 µg mL(-1)) of the plant.


CONCLUSION
The present study indicates that both essential oil of P. klotzsdhianum and the isolate 1-butyl-3,4-methylenedioxybenzene are potential resources for A. aegypti larva control. This is the first report of the biological activities of the oil and isolated compound.