Improving the flavor, bioactivity, and metabolic characteristics of corn silk by probiotic co-fermentation

Corn silk, an agricultural by-product rich in bioactive compounds, has long remained underutilized. In this study, we systematically examined how probiotic co-fermentation influences the bioactivity, flavor profile, and metabolic landscape of corn silk. The results demonstrated that fermentation significantly enhanced the total phenolic content by 73.31 % and flavonoid content by 80.20 %, along with a substantial improvement in antioxidant capacity. Volatile compound analysis identified 36 key aroma-related substances. Notably, 4-methylguaiacol and 4-ethylguaiacol contributed to both improved flavor and antioxidant function, highlighting a synergistic relationship between sensory quality and bioactivity during fermentation. Non-targeted metabolomics further revealed substantial changes in the metabolic profile post-fermentation, with 110 differential metabolites identified—75 upregulated and 35 downregulated. These metabolites were primarily enriched in the TCA cycle, phenylpropanoid biosynthesis, and amino acid metabolism pathways. Together, these findings uncover the molecular mechanisms by which probiotic fermentation remodels metabolic networks to enhance both the functional and sensory attributes of corn silk. This work offers a theoretical foundation and technical guidance for the high-value utilization of agricultural by-products and the development of functional foods.