LARVICIDAL AND ANTIBACTERIAL EFFICACY OF GREEN SYNTHESISED SILVER NANOPARTICLES USING MELIA DUBIA

Objectives: Plant extracts seems to be a better alternative to control pathogenic organisms due to the presence of many bioactive compounds. In addition, the plant mediated synthesized silver nanoparticles also have important applications in the field of biology, the present study aims to study the activity of AgNP's (Silver Nanoparticles) synthesized using the leaves of Melia dubia against the 4th instar larvae of Culex quinquefasciatus and pathogenic microbes Methods: The synthesized AgNP's were characterized by UV-Vis spectrum, Scanning Electron Microscopy (SEM), Energy dispersive X-ray spectroscopy(EDX) and Fourier Transform Infrared Spectroscopy (FTIR). The 4th instar larvae of Culex quinquefasciatus were exposed to different concentrations of aqueous leaf extract (5, 10, 15, 20, 25ppm) and Silver nanoparticles (1, 2, 3, 4, 5 ppm) for 24 hours period. The antibacterial activity was measured by disk diffusion method against Bacillus subtilis, Proteus mirabilis, Klebseilla pneumoniae, Escherichia coli, and Vibrio cholerae. Results: The observations reveal that the silver nanoparticles synthesized using Melia dubia leaves were more effective than the crude leaf extract of the plant over Culex quinquefasciatus and microbes tested. Moreover, the results of metabolites also revealed that the AgNP's significantly altered the carbohydrates and protein level in the 4th instar larvae of Culex quinquefasciatus. Conclusion: The larvicidal and bactericidal activities are due to various phytoconstituents coated with the nanoparticles. It is further inferred from the results that the use of AgNP's for the control of targeted vectors is to eradicate disease transmitting mosquitoes as well as to control microbes