Green synthesis and characterization of zinc oxide nanoparticles with antibacterial and antifungal activity

The present study involves synthesis of zinc oxide nanoparticles (ZnO-NPs) through a rapid, cost effective and eco-friendly method using four different plant extracts. The plants used in this study were Beta vulgaris, Cinnamomum tamala, Cinnamomum verum, Brassica oleracea var. Italica. Characterizations of ZnO-NPs were done using X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM). Moreover, the antibacterial activities of ZnO-NPs were demonstrated using both gram negative and gram positive bacteria such as Escherichia coli and Staphylococcus aureus, respectively. All samples of ZnO-NPs presented antibacterial activity against both gram negative and positive bacteria, while ZnO-NPs prepared using Beta vulgaris was found to be inactive towards S. aureus. The antifungal activity of ZnO-NPs was also demonstrated using Candida albicans and Aspergillus niger fungal stains. It was found that ZnO-NPs prepared using Beta vulgaris were active against A. niger, while those prepared from Cinnamomum tamala were active against C Albicans. Also, ZnO-NPs prepared from the extract of Brassica oleracea var. italica have shown activity against both the fungal stains. Overall, a rapid, cost-effective, environmentally-friendly method for ZnO-NPs synthesis was demonstrated, which can be used as a potential antimicrobial agent against different microbial species. (C) 2020 Elsevier B.V. All rights reserved.