Antibacterial Efficacy of Silver Nanoparticles Synthesized by a Green Method Using Bark Extract of Melia azedarach L

Antibacterial efficacy of silver nanoparticles developed by a phyto-synthesis method has been investigated and presented in this work. Silver nanoparticles of mean size 30-45 nm having spherical shape and crystalline structure were synthesized at room temperature through bioreduction of silver nitrate solution treated with bark extract of Melia azedarach. Formation of nanoparticles was observed by the color change in the reaction medium which was further established with UV-vis spectroscopy. Structural and morphological characterizations on silver nanoparticles were made by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infra-red spectroscopy (FTIR) analyses. FTIR spectroscopic analysis has revealed the presence of biomolecules enveloped around the silver nanoparticles. Antibacterial efficacy of these nanoparticles was analyzed against Escherichia coli and Klebsiella pneumonia by measuring the zones of inhibition on solid growth medium. These silver nanoparticles have shown efficient inhibitory activity against the tested bacterial strains. It is believed that the proposed biocompatible, eco-friendly, and green synthesis method would lead to development of novel biomedical products based on silver nanoparticles.