Fabrication of highly effective mosquito nanolarvicides using an Asian plant of ethno-pharmacological interest, Priyangu (Aglaia elaeagnoidea): toxicity on non-target mosquito natural enemies

Mosquitoes threaten the lives of humans, livestock, pets and wildlife around the globe, due to their ability to vector devastating diseases. Aglaia elaeagnoidea , commonly known as Priyangu, is widely employed in Asian traditional medicine and pest control. Medicinal activities include anti-inflammatory, analgesic, anticancer, and anesthetic actions. Flavaglines, six cyclopenta[b]benzofurans, a cyclopenta[bc]benzopyran, a benzo[b]oxepine, and an aromatic butyrolactone showed antifungal properties, and aglaroxin A and rocaglamide were effective to control moth pests. Here, we determined the larvicidal action of A . elaeagnoidea leaf aqueous extract . Furthermore, we focused on Priyangu-mediated synthesis of Ag nanoparticles toxic to Culex quinquefasciatus , Aedes aegypti and Anopheles stephensi. The plant extract and the nanolarvicide were tested on three mosquito vectors, following the WHO protocol, as well as on three non-target mosquito predators. Priyangu-synthesized Ag nanoparticles were characterized by spectroscopic (UV, FTIR, XRD, and EDX) and microscopic (AFM, SEM, and TEM) analyses. Priyangu extract toxicity was moderate on Cx. quinquefasciatus (LC 50 246.43; LC 90 462.09 μg/mL), Ae. aegypti (LC 50 229.79; LC 90 442.71 μg/mL), and An. stephensi (LC 50 207.06; LC 90 408.46 μg/mL), respectively, while Priyangu-synthesized Ag nanoparticles were highly toxic to Cx. quinquefasciatus (LC 50 24.91; LC 90 45.96 μg/mL), Ae. aegypti (LC 50 22.80; LC 90 43.23 μg/mL), and An. stephensi (LC 50 20.66; LC 90 39.94 μg/mL), respectively. Priyangu extract and Ag nanoparticles were found safer to non-target larvivorous fishes, backswimmers, and waterbugs, with LC 50 ranging from 1247 to 37,254.45 μg/mL, if compared to target pests. Overall, the current research represents a modern approach integrating traditional botanical pesticides and nanotechnology to the control of larval populations of mosquito vectors, with negligible toxicity against non-target including larvivorous fishes, backswimmers, and waterbugs.