Green Synthesis of Silver Nanoparticle using Kalanchoe pinnata leaf extract and its Antibacterial Effect against Gram-Positive and Gram-Negative Species

Abstract

This study presents a rapid, non-toxic, eco- friendly procedure for the synthesis of silver nanoparticle (Ag NP) using Kalanchoe pinnata fresh leaves extract. The plant extract acted as a reducing agent as well as a capping and stabilization agent. Synthesis of nanoparticle was estimated by visual interpretation as a preliminary test and UV-visible Spectroscopy showing standard peak at the range of 430 nm as a confirmatory test. X-ray diffraction assay (XRD) confirmed the crystalline nature of synthesized nanoparticle. Fourier transform infrared spectroscopy (FT-IR) analysis was performed to identify the functional groups of plant involved in the reduction of metallic silver. Size estimation of nanoparticle was conducted through Scanning electron microscopy (SEM) analysis which confirmed the size range of nanoparticle as 50-70 nm. Further characterization of biosynthesized nanoparticle included Atomic force microscopy (AFM) imaging which depicted the topography of the nanoparticle. Elemental composition analysis of the nanoparticles was conducted using Energy dispersion analysis of X-ray (EDAX) analysis that demonstrated the presence of silver in great proportion. Potent antibacterial activity of green synthesized silver nanoparticle have been found against both Gram-positive species (Staphylococcus sp., Bacillus sp., Listeria sp., Salmonella sp.) and Gram-negative bacteria like E.coli sp.