Mosquitocidal efficacy of niloticin, isolated from Limonia acidissima L. (Rutaceae) against filarial vector Culex quinquefasciatus Say. (Diptera: Culicidae)

Common household mosquitoes are a major public nuisance, and mosquito-borne diseases are the greatest threat to public health. In the current situation, it would be ideal to control mosquito populations without harming the environment. The present study aims to evaluate the mosquitocidal efficacy of fractions and the active principle niloticin isolated from the leaves of Limonia acidissima Linn. against the life stages of Culex quinquefasciatus Say mosquitoes. The concentrations used to screen the fractions were 10.0, 7.5, 5.0, and 2.5 ppm and the active compound niloticin was tested at concentrations of 2.0, 1.5, 1.0, and 0.5 ppm on the larval (L3) and pupal stages of Cx. quinquefasciatus. The results showed that fraction-8 recorded the highest mosquitocidal activity, and the lethality results (LC50) after 24 hours were 3.44 ppm for larvae and 5.14 ppm for pupae of Cx. quinquefasciatus, respectively. Similarly, LC50 of niloticin at 24 hours were 0.42 ppm for larvae and 0.51 ppm for pupae of Cx. quinquefasciatus, respectively. In addition, at a concentration of 2.0 ppm, niloticin showed an ovicidal activity of 94.4% and a deterrent effect on oviposition of 100% and exhibited considerable growth disruption. In conclusion, the results indicate that niloticin can be used for vector mosquito control.