Green synthesized ZnO nanoparticles by Saccharomyces cerevisiae and their antibacterial activity and photocatalytic degradation

Abstract

Many research papers are currently being written about various methodologies for the green synthesis of ZnO nanoparticles. In this study, ZnO nanoparticles were prepared by green synthesis method using baker’s yeast (Saccharomyces cerevisiae). The characterization of the produced ZnO nanoparticles involved the utilization of XRD, FTIR, SEM, and TEM. The investigation involved the assessment of the antimicrobial potential and photocatalytic degradation efficacy of the synthesized materials through the utilization of Eriochrome Black T (EBT). The results indicate that the ZnO nanoparticles exhibit a spherical morphology, exhibiting diameters ranging from 13.0 to 20.0nm, with an average particle size of 15.0nm. The antimicrobial efficacy against (S. aureus) gram-positive and (E. coli) gram-negative bacteria was tested through the conduction of zone of inhibition (ZOI) and minimum inhibitory concentration (MIC) tests. This research focused on the study of the photocatalytic-degradation of EBT in the presence of ultraviolet light. The experiments focused on the impact of various factors, such as pH levels, initial EBT concentration, and nanocatalyst dosage, on the observed photocatalytic efficiency. In the in vitro ZOI and MIC results assay, it was observed that ZnO nanoparticles (NPs) exhibited greater efficacy against gram-positive S. aureus, with a ZOI measuring 23.1 mm and a MIC of 0.625 μg/ml. In contrast, the effectiveness of ZnO-NPs against gram-negative E. coli was comparatively lower, as indicated by a ZOI of 17.0 mm and a MIC of 1.250μg/ml. The greatest EBT elimination, which achieved 83.0% in equilibrium, was found employing 20.0mg of ZnO NPs at pH 3.0, according to the photocatalytic activity results. The synthetic ZnO NPs are powerful antibacterial agents that are effective against tested bacteria and may be used in the treatment of wastewater.