Objectives: To study the larvicidal effect of Vitex negundo Linn against mosquito larvae by larvicidal bioassay and in silico molecular docking studies. Methods: The larvicidal bioassay of Vitex negundo Linn was assessed by using WHO standard protocol and an in silico molecular docking study was performed by using Molegro Virtual Docker against Culex quinquifasciatus. The early third instar larvae of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus were exposed to the extract concentrations in three replicates and different temephos concentration were taken as positive control and solvent control was also used. Results: The study results shows that of Vitex negundo Linn possess the potential larvicidal activity against third instar larvae of Culex quinquifasciatus when compared to Aedes aegypti L and Aedes albopictus. Percentage mortality and half-maximal effective concentration (EC50) value were calculated against the above mentioned three species like wise Culex quinquifasciatus (83.77 ppm), Aedes aegypti (341.7 ppm), and Aedes albopictus (487.9 ppm). The highest larval mortality was found against Culex quinquifasciatus of 100 % at 500 parts per million. In silico molecular docking studies using Molegro Virtual Docker against Odorant binding protein (PDB: 2L2C) of Culex quinquifasciatus was performed as it showed better results in in vitro study. The results reveal that phytoconstituent like Vitexicarpin showed good docking scores against the Odorant Binding Protein 2L2C and the moldock score of Vitexicarpin was found to be -87.3733, whereas moldock score of standard Azadirachtin was found to be -110.77. Conclusion: The present study reveal that the Vitex negundo Linn possess the potential larvicidal activity against the Culex quinquifasciatus species.
Key words: Vitex negundo Linn, Aedes aegypti L, Culex quinquefasciatus, Aedes albopictus, Molegro Virtual Docker 6.0, Odorant binding Protein, Larvicidal.