Evaluation of Larvicidal Activity of Essential Oil from Leaves of Coccinia grandis against Three Mosquito Species

Background: To study the chemical constituents and larvicidal activity of essential oil extracted from the leaves of Coccinia grandis against three mosquito species. Methods: Essential oil was extracted by hydro distillation using clevenger apparatus and was analyzed for chemical constituents by gas chromatography-mass spectrophotometry (GC-MS). Larvicidal activity was recorded after 12 and 24h of post-exposure against three mosquito species, Anopheles stephensi, Aedes aegypti and Culex quinquefascia-tus. Dead larvae were identified when they failed to move after probing with a needle in the siphon or cervical re-gion. The LC50 and LC90 values for three mosquito larvae were calculated by Probit analysis. Results: The GC-MS analysis revealed that essential oil contains 23 different constituents. Out of these 23 constitu-ents, major constituents identified were n-tetracosane (39.18%), n-eicosane (30.04%), tetratriacotane (2.97%), 7-oc-tadecanal (2.81%), and tricosane (2.31%). Essential oil from leaves of Coccinia grandis exhibited significant larvi-cidal activity against An. stephensi with LC50 and LC90 values 39.41ppm and 123.24ppm, respectively. This was fol-lowed by Ae. aegypti and Cx. quinquefasciatus with LC50 and LC90 values of 48.20ppm, 131.84ppm and 52.80ppm, 135.48ppm, respectively after 24h of exposure. Conclusion: The results could be useful in developing a cost effective, ecofriendly, region specific and practical strategy for the control of mosquito vectors.