Biosynthesis of silver nanoparticles using Cassia tora leaf extract and its antioxidant and antibacterial activities

A single step green synthesis of silver nanoparticles (AgNPs) from silver nitrate (AgNO3) using Cassia tora leaves extract as reducing agent by a simple and ecofriendly method in room temperature. The biosynthesized nanoparticles were characterized by UV-Vis, Scanning electron microscopy (SEM) coupled with X-ray energy dispersive spectrophotometer (EDAX), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). In UV-Vis spectroscopy results, the lambda(max) observed at 425 nm. The AgNPs synthesized were spherical, hexagonal and irregular in shapes. The EDAX and XRD spectrum confirms that the presence of silver ions and crystalline nature of synthesized AgNPs. FTIR showed the functional groups such as C=O, N-H and C-N groups involved in the reduction of Ag+ to Ag. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay was performed and it showed percentage inhibition in concentration dependent manner. The synthesized AgNPs showed antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis in different extents and the higher activity was observed in Escherichia coli. (C) 2015 Published by Elsevier B.V. on behalf of The Korean Society of Industrial and Engineering Chemistry.