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 quinquefascia­tus . dead larvae were identified when they failed to move after probing with a needle in the siphon or cervical re­gion. the lc 50 and lc 90 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 constitu­ents, major constituents identified were n-tetracosane (39.18%), n-eicosane (30.04%), tetratriacotane (2.97%), 7-oc­tadecanal (2.81%), and tricosane (2.31%). essential oil from leaves of coccinia grandis exhibited significant larvi­cidal activity against an. stephensi with lc 50 and lc 90 values 39.41ppm and 123.24ppm, respectively. this was fol­lowed by ae. aegypti and cx. quinquefasciatus with lc 50 and lc 90 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.