Bioengineering and optimization of PEGylated zinc nanoparticles by simple green method using Monascus purpureus, and their powerful antifungal activity against the most famous plant pathogenic fungi, causing food spoilage

Abstract This study aimed to develop an innovative polgylated zinc nanoparticles (PEGylated ZnNPs) by polygylation of zinc nanoparticles (ZnNPs), by a safe simple green route using fungal filtrate of Monascus purpureus, and to investigate its antifungal activity against food spoilage fungi. The produced nanoparticles were initially identified by the formation of white precipitate and the appearance of strong peak spectra at 430–450 nm, using UV visible spectroscopic technique. The formation of PEGylated-ZnNPs was characterized by Dynamic Light Scatter (DLS), Transmission Electron microscopy (TEM), and Fourier Transformed Infrared (FTIR). All analyses confirmed the presence of rounded well dispersed nano-zinc with size range of 33.6–78.1 nm. Optimization conditions showed maximum absorbance peaks at pH-9, 40 °C with 3 mM ZnNO3 and 3d of incubation. The nanoparticles showed potent antifungal activity against six species of the most common food spoilage fungi, including Fusarium solani, Fusarium sporotrichioides, Fusarium oxysporum, Rhizocotonia solani, and macrophomina phaseolina. Scanning electron microscopic (SEM) analysis of the most inhibited pathogen, F. sporotrichioides, treated with nanoparticles solution, showed damaged non sporulated hyphae compared to the untreated sample which showed normal sporulated hyphae. The potential activity of PEGylated-ZnNPs against food spoilage fungi encourage their future applications in different vital fields such as biomedical, industrial and food packaging. This study proposes a modern alternate route with a perfect biotechnological technique for the biosynthesis of PEGylated-ZnNPs which will direct the fabrication of nanocomposite to microbial pathway.