Plant Mediated Synthesis of ZnO Nanoparticles Using Butea monosperma Plant Extract and Their Antibacterial Applications

Plant based nanoparticles (NPs) has become an emerging field in nanotechnology in terms of cost efficiency, less hazardous, biocompatibility and ecologically benignancy. Further, These NPs are being extensively studied for their use as nanomedicines and novel antibacterial agents due to increased growth of hazardous bacteria and their increased resistance to traditional antibiotics. The present studiesfocused on biosynthesis of zinc oxide (ZnO) NPs using the chloride derivative of zinc and aqueous extract of Butea monosperma (BM) plant and its antibacterial applications on food borne pathogens. Scanning electron microscopy (SEM) reveals the formation of mixed shaped (spherical and hexagonal) ZnO NPs with size ranging between 20-90 nm. The elemental composition of various constituents present in the resulting samples was confirmed from energy dispersive X-ray (EDX). XRD pattern suggested crystalline nature with hexagonal wurtzite structure of ZnO NPs. The Scherrer formula is used to evaluate the average crystallite size of the synthesized NPs ranges from 15 to 85 nm. Furthermore, the Tauc plot method was employed to determine the bandgap energies of the biosynthesized ZnO NPs using UV-visible spectra. These NPs were found to be effective against bacterial strains; Staphylococcus aureus (MTCC 96), Bacillus cereus (MTCC 1272), Stenotrophomonas maltophilia (MTCC 4383), Shigella flexneri (MTCC 1457). Overall, this present research describes that synthesized ZnO NPs hold significant importance as potential antibacterial agents against gram positive bacteria.