Chapter 10 - Evaluation of antimicrobial, antioxidant, and photocatalytic activity of zinc oxide nanoparticles synthesized from Parmotrema perlatum

Abstract

The aim of the present study was evaluation of antimicrobial, antioxidant, and photocatalytic potential of zinc oxide nanoparticles (ZnONPs) synthesized by using Parmotrema perlatum. The characterization of nanoparticles was done by UV-vis spectrophotometer, Fourier transform infrared (FTIR) spectroscopy analysis, and transmission electron microscopy. The results of various techniques confirmed the presence and formation of ZnONPs. UV-visible spectrum of ZnONPs showed maximum peak at 368nm. FTIR spectrum determines the various organic and inorganic functional groups, which are responsible for reduction and stabilization of ZnONPs. Size of ZnONPs was in rang of 40–70nm and spherical in shape. The antimicrobial activity was evaluated against pathogenic microorganisms by minimum inhibitory concentration and time kill study. ZnONPs showed broad spectrum of antimicrobial activity and time kill study revealed that synthesized ZnONPs effectively inhibit growth of microorganisms. ZnONPs combination with antibiotics shows enhanced synergistic antimicrobial activity against microorganisms. ZnONPs shows good antioxidant 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical activity. ZnONPs were evaluated for photocatalytic degradation of methylene blue, Malachite green and Congo red dyes under UV and solar irradiation at different time interval. ZnONPs showed good the photocatalytic degradation of dye under the irradiation of UV light as compared to sun light. The synthesized ZnONPs have shown good effective like antimicrobial, antioxidant, and photocatalytic property, and hence, it may be used for different applications.