Metabolite profiling and enhanced antimicrobial and nematicidal activities of zinc oxide nanoparticle-biofortified Pleurotus mushrooms

In the present investigation, the second most widely consumed edible mushrooms of Pleurotus species, namely P. djamor, P. florida and P. sajor-caju, were biofortified with zinc oxide nanoparticles (ZnONPs) and screened for bioactives with Gas Chromatography- Mass Spectrometer (GC-MS), governing potent biological activities (antioxidant, antibacterial, anti-fungal and nematicidal), checked subsequently. The fruiting body extracts of Pleurotus spp. control (0 ppm) and ZnONPs treated (20 ppm) were found to have distinct chemical compositions in GC-MS analysis, but certain compounds were also found common to both extracts. All three fortified ZnONP extracts exhibited significantly greater biological activity than controls, including antibacterial activity against Erwinia amylovora, Bacillus subtilis, Escherichia coli and Xanthomonas oryzae, anti-fungal against Fusarium oxysporium and Sclerotinia sclerotiorum and nematicidal activity against Meloidogyne incognitia. ZnONP biofortification generally increases the relative abundance of shared bioactive metabolites, such as squalene, methyl palmitate, methyl linoleate, and ergosterol derivatives, in a species-specific manner, which plausibly explains the enhanced biological activities observed in treated extracts. GC-MS analysis revealed distinct but partially overlapping chemical profiles between control and 20 ppm ZnONP-treated extracts of all three Pleurotus species. These findings demonstrate that ZnONP biofortification enhances the nutritional and health promoting value of Pleurotus spp. and augmetns their potential as a plant protectant, establishing dual benfits for the valorization of edible oyster mushrooms.