Transcriptomic and Metabolomic Analyses of the Mechanisms Underlying Zearalenone Removal by Lactobacillus paracasei

Zearalenone (ZEN) is a mycotoxin produced by Fusarium species that is harmful to agricultural crops. Therefore, the prevention and control of ZEN contamination is an important concern for food safety. Lactobacillus paracasei 85 is a well-recognized probiotic with considerable potential for mycotoxin biocontrol owing to its diverse probiotic properties and antimicrobial activity. Based on its reported potential, we aimed to evaluate its ability to degrade ZEN using degradation assays under optimal conditions. Transcriptome sequencing, untargeted metabolomics, and integrated bioinformatics analyses were conducted to explore the molecular mechanisms underlying ZEN removal. Transcriptomic analysis showed that the strain activated central carbon and secondary metabolism during ZEN removal, and all seven differentially expressed genes closely related to carbohydrate metabolism were downregulated. Metabolomic analysis revealed that lipid and amino acid metabolism, in addition to carbohydrate metabolism, played important roles in ZEN removal. Correlation analysis between carbohydrate metabolism-related genes and their metabolites revealed that these genes were significantly associated with four metabolites: myo-inositol, guanosine, glycolic acid, and trehalose. As key nodes in the carbohydrate metabolism pathway, changes in the expression of these four metabolites and their interactions with genes may represent key regulatory factors responsible for the overall downregulation of carbohydrate metabolism.