Antimicrobial Potential of Green Synthesized Silver Nanoparticles From the Fruit of Azadirachta indica a High-Valued Medicinal Plant

Abstract

The activity and stability of nanoparticles synthesized from plants; green-synthesized nanoparticles are obtaining more consideration from scientists. This work aimed to synthesize the green silver nanoparticles (AgNPs) using the fruit extract of Azadirachta indica A. Juss. The fruit extract acts as both a capping and reducing agent. The physicochemical properties of synthesized nanoparticles were studied through x-ray diffraction (XRD), FT-IR, UV-vis, scanning electron microscopy (SEM), and EDX. Furthermore, antioxidant properties and antibacterial activity of the nanoparticles were also studied. The reaction was preceded under sunlight, and the color of the reaction mixture changed from colorless to dark brown, indicating the production of Ag nanoparticles. A UV-vis analysis revealed an absorption peak of 429 nm, which was measured after 30 min of reaction. The XRD spectroscopy results suggest that the nanoparticles are crystalline with an average diameter of 36.50 µm. SEM images show that the majority of the AgNPs are spherical and fairly distributed. The obtained AgNPs showed efficient antibacterial activity against gram-negative (Escherichia coli) and gram-positive (Staphylococcus) bacterial species. Surprisingly, the synthesized Ag nanoparticles from A. indica fruit by the DPPH assay method show 55% antioxidant activity.