Investigation of physicochemical characteristics and antifungal activity of zinc oxide nanoparticles

Fungal diseases are major causes of deterioration of food and agricultural products. In this study, zinc oxide nanoparticles (ZnONPs) synthesized via a microwave-based method were employed to eradicate fungal pathogens. FESEM of ZnONPs revealed nearly spherical particles with a mean diameter of 46 nm. UV–vis spectroscopy shows a characteristic absorption peak at 365 nm, confirming the formation of ZnONPs. Tauc’s relation analysis found the bandgap energy to be approximately 3.2 eV. XRD analysis shows the crystalline nature of the ZnONPs, confirming a hexagonal wurtzite structure of the synthesized product. FTIR and EDX analyses confirmed the presence of ZnONPs. Intensities of Raman peaks at 438.42 cm −1 correspond to lattice vibrations of the Zn–O bond, confirming the unique characteristic of ZnO. The antifungal efficacy of ZnONPs was tested against Aspergillus niger , Penicillium sp. , and Candida albicans at concentrations ranging from 5 to 80 mg/mL. These results demonstrated significant inhibition of fungal growth, with complete inhibition at a concentration of 80 mg/mL after 48–96 h of incubation. This work not only introduces a fast technique for ZnONP synthesis but also to explore the antifungal efficacy of the synthesized ZnONPs, which leads to different applications as antimicrobial agents.