Chemical profile changes in Peanut seeds infected with aspergillus flavus via widely targeted metabolomics

Peanut seeds are enriched with protein and fatty acids, making them susceptible to infection by Aspergillus flavus (A. flavus). The infected seeds are harmful to human health due to the aflatoxin contamination. Despite ongoing research, a comprehensive understanding of the metabolite variations in peanut seeds during A. flavus infection remains elusive. In this study, we established a detailed endogenous chemical profile consisting of 1462 metabolites in shelled peanut seeds, identified 895 and 671 differentially expressed metabolites (DEMs) on the 3rd and 6th days post-infection by A. flavus, respectively. Among these, 425 DEMs were common to both profiles, with the majority of co-expressed DEMs displaying an up-regulated expression pattern in response to A. flavus infection. Further metabolites interaction analysis indicated that phenolic acids significantly correlated with A. flavus infection. Specifically, five metabolites classified as phenolic acids demonstrated the ability to repress A. flavus growth in vitro. The anti-infection properties of peanut phenolic acids were confirmed by their higher content in resistant peanut varieties. Overall, our study elucidates the chemical profile of endogenous metabolite variations in A. flavus infected peanut seeds, demonstrating that elevated phenolic acid content can be employed as a biomarker for identifying peanut varieties resistant to A. flavus infection.