Unravelling the antifungal mechanism of phytic acid on <i>Aspergillus flavus</i> development and aflatoxin B1 biosynthesis

<i>Aspergillus flavus</i> (<i>A. flavus</i>) is a plant pathogenic fungus that produces toxic and carcinogenic aflatoxins, posing a threat to food safety and human health. As a kind of food additive, phytic acid (PA) exhibits excellent antimicrobial activity. However, the antifungal effects of PA against <i>A. flavus</i> are not well understood. Here, transcriptomic and biochemical analyses were carried out to investigate the inhibitory effects of PA against <i>A. flavus</i> and potential mechanisms. Our findings demonstrated that PA effectively inhibited the vegetative growth, conidiation and aflatoxin B1 (AFB1) production of <i>A. flavus</i>. In addition, we found that PA also suppressed the pathogenicity of <i>A. flavus</i> on peanut and maize seeds. The transcriptomic analysis confirmed that the differentially expressed genes (DEGs) were involved in development, aflatoxin biosynthesis, oxidative stress, ergosterol biosynthesis, and the MAPK signalling pathway in <i>A. flavus</i>. Biochemical experiments further demonstrated that PA could destroy cell membrane integrity and induce reactive oxygen species (ROS) accumulation, eventually resulting in defects of development and AFB1 biosynthesis in <i>A. flavus</i>. Taken together, this research enhances understanding of the antifungal mechanism of PA, and provides novel insights into its potential as a food additive to prevent and control <i>A. flavus</i> contamination.