Characteristic Structures of Different Stilbenes Distinguish the Impact on Ochratoxin A Biosynthesis Intermediate Pathway and Metabolites of Aspergillus carbonarius

In this paper, we accurately pinpointed the inhibitionsites ofochratoxin A (OTA) synthesis pathway in Aspergilluscarbonarius acted by stilbenes from the perspectiveof oxidative stress and comprehensively explored the relationshipbetween the physical and chemical properties of natural polyphenolicsubstances and their biochemical properties of antitoxin. To facilitatethe application of ultra-high-performance liquid chromatography andtriple quadrupole mass spectrometry for real-time tracking of pathwayintermediate metabolite content, the synergistic effect of Cu2+-stilbenes self-assembled carriers was utilized. Cu2+ increased the generation of reactive oxygen species to accumulatemycotoxin content, while stilbenes had the inhibitory effect. Theimpact of the m-methoxy structure of pterostilbeneon A. carbonarius was found to be superiorto that of resorcinol and catechol. The m-methoxystructure of pterostilbene acted on the key regulator Yap1, downregulated the expression of antioxidant enzymes, and accuratelyinhibited the halogenation step of the OTA synthesis pathway, thusaccumulating the content of OTA precursors. This provided a theoreticalbasis for the extensive and efficient application of a wide rangeof natural polyphenolic substances for postharvest disease controland quality assurance of grape products.