A Facile One-Pot Synthesis of Eco-Friendly Nanoparticles Using Carissa carandas: Ovicidal and Larvicidal Potential on Malaria, Dengue and Filariasis Mosquito Vectors

Mosquito-borne diseases represent a major human and animal health problem in all tropical and subtropical countries worldwide. In this study, we investigated the one-pot synthesis of silver nanoparticles (AgNPs) using a cheap leaf extract of Carissa carandas (Apocynaceae). Bio-reduced AgNPs were characterized by UV-visible spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction analysis, atomic force microscopy, scanning electron microscopy and transmission electron microscopy. The acute toxicity of C. carandas extract and green-synthesized AgNPs was evaluated on eggs and larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. AgNPs showed high toxicity against A. stephensi, A. aegypti, and C. quinquefasciatus larvae with LC50 values of 14.33, 15.69 and 16.95 mu g/mL, respectively. A single treatment with AgNPs tested at 60 mu g/mL led to no egg hatchability. The egg rafts of C. quinquefasciatus were more resistant to the toxic action of AgNPs if compared to A. aegypti and A. stephensi. C. carandas-fabricated AgNPs were found safer to non-target organisms Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 ranging from 1097.87 to 17249.89 A mu g/ml. Overall, this research shed light on the mosquitocidal potential of C. carandas, a potential bio-resource for rapid, cheap and effective synthesis of poly-disperse and stable silver nanocrystals.