Anopheles gambiae Control and Antibacterial Activity of Silver, Gold, and their Alloy Nanoparticles Synthesized Using Pleurotus ostreatus

Mosquitoes, the primary malaria vectors in Nigeria, have developed increasing resistance to synthetic insecticides, necessitating the search for eco-friendly alternatives. This study investigates the insecticidal and biomedical properties of silver nanoparticles (AgNPs), gold nanoparticles (AuNPs), and silver-gold alloy nanoparticles (Ag-AuNPs) synthesized via a green method using Pleurotus ostreatusnbsp;extracts. Nanoparticles were characterized using UV-visible spectroscopy and Fourier-transform infrared spectroscopy (FTIR). Their larvicidal and pupicidal efficacy was tested at 1–30 µg/mL concentrations over 12 and 24 hours, while adult mosquitoes were exposed to nanoparticle-infused coil fumes. Additionally, antibacterial activity against eight clinical bacterial isolates was evaluated. UV-visible spectroscopy showed maximum absorbance at 430, 550, and 540 nm for AgNPs, AuNPs, and Ag-AuNPs, respectively, while FTIR analysis confirmed functional group interactions at 3778, 3262, and 3037 cm¹. Mortality increased with concentration and exposure time, with a maximum effect at 170 µg/mL for adult mosquitoes. Antibacterial tests revealed inhibition zones of 5–12 mm at 10–50 µg/mL concentrations. These findings highlight the potential of Pleurotus ostreatus-derived nanoparticles as effective biopesticides with promising antibacterial applications.