Antifungal Activity of ZnO Nanobullets against Schizosaccharomyces pombe

Abstract

In this study, an enhanced antifungal response of ZnO nanobullets (NBs) against Schizosaccharomyces pombe is reported. The ZnO NBs were prepared by alkali precipitation method and confirmed by microscopic, morphological and optical studies using SEM, EDX, TEM, HRTEM and photoluminescence (PL) spectroscopic techniques. Growth kinetics and MIC studies were conducted following the growth inhibition percentage studies. Colony forming assay, well diffusion, disc diffusion, N-acetyl cysteine (NAC) effect on S. pombe growth, trypan blue study, cellular reactive oxygen species (ROS) quantification using H2DCFDA dye, Bradford assay, DNA fragmentation and all other relevant protocols were performed in antifungal studies. ZnO nanobullets (NBs) were shown by SEM and TEM examinations to have an average size of 50 nm. The hexagonal wurtzite structure of ZnO NBs was confirmed by HRTEM’s lattice fringe findings. Defectrelated visible emissions at 412, 436, 457 and 564 nm were confirmed via PL analysis. It was found that ZnO NBs resulted in complete growth inhibition of S. pombe at 200 μg/mL. When S. pombe was treated with ZnO NBs, the Bradford assay revealed enhanced protein leakage, but the TBARS assay revealed lipid peroxidation brought on by reactive oxygen species (ROS). When S. pombe was exposed to ZnO NBs, the H2DCFDA assay revealed increased ROS generation, whilst the trypan blue assay revealed increased cell membrane fusion and lower viability. According to present study, the treatment with ZnO NBs caused S. pombe to develop damaged cell walls, leaky proteins and DNA breakage.