Evaluation of Larvicidal and Repellent Activity of Nanocrystal Emulsion Synthesized from F. glomerata and Neem Oil Against Mosquitoes

Aedes aegypti , Culex quinquefasciatus , and Anopheles stephensi are the domestic vectors of tropical diseases include dengue, malaria, zika, filariasis. To control these vectors, ethnobotanical knowledge provides pragmatic solutions that are compatible with nature. Hence an attempt has been made to coalesce the ethnobotanical knowledge of tribes from Kadambur hills with the nano emulsification technology to formulate an herbal-based larvicidal and repellent nanocrystal emulsion. The ethanol extract from Ficus glomerata was used as the larvicidal and repellant agent against A. aegypti , C. quinquefasciatus and A. stephensi. For the improved stability, shelf life and sustained release of bioactive compounds, a novel methodology has been followed to synthesize nanocrystal emulsion. F. glomerata extract based nanocrystal emulsion (FON) was prepared by ultrasonication and characterized by Zeta potential (− 73.6 mV) and dynamic light scattering (104 nm), ATR-FTIR for the functional groups, high-resolution transmission electron microscope and selective area energy diffraction. The maximum shelf life was evaluated to be more than 3 years. The prepared nanocrystal emulsion was challenged for larvicidal and repellent activities against all the three species. The FON larvicidal results were comparable to the conventional neem oil based nanoemulsion and the repellant activity results were effective than the commercial formulation.