Efficient biogenesis of ZnO nanoparticles using extracellular extract of Saccharomyces cerevisiae : Evaluation of photocatalytic, cytotoxic and other biological activities.

This research aimed to synthesize zinc oxide nanoparticles (ZnO NPs) using an extracellular extract of Saccharomyces cerevisiae. The physical characteristics of the biosynthesized NPs were studied using XRD, FTIR, FESEM, and EDS. Microscopic study and spectroscopic examination depicted spherical ZnO NPs < 30 nm diameter in size, relatively stable, and bearing a hexagonal phase. Antibacterial study of these NPs against food pathogens showed enhanced higher antibacterial activity on Staphylococcus aureus in a dose-dependent manner. Concentration-dependent antioxidant activity was also observed for ZnO NPs in both DPPH and FRAP assay. Also, the anticancer study of these NPs against MCF-7 cancer cell line demonstrated a considerable cytotoxic effect in a concentration-dependent manner. Evaluation of photocatalytic activity indicated that the highest removal of MB was achieved to be 67% with an initial ZnO NP concentration of 12 mg/mL under UV light. The results suggested the biosynthesis of ZnO NPs in a cost-less approach which can be lead to sustainable development for its use as photocatalyst and anti-cancer therapeutic agents.