Interaction between Lentinula edodes protein and cereal polysaccharide under precision nutrition strategies: insights...

Despite the burgeoning research on protein-polysaccharide systems, a unified consensus on the functional significance of their interactions remains elusive, particularly concerning how protein-intrinsic characteristics dictate the structural specificity and subsequent gut-modulatory effects of the complexes. This study explored the interactions between two Lentinula edodes protein varieties (LEP: Hubei 1513 and Zhejiang 1513) and three β-glucans (βG: barley, oat, yeast). LEP-βG complexes were prepared by wet glycosylation, and their physicochemical, in vitro digestive and fermentative properties were characterized. βG binding modified the protein conformation, enhanced the structural stability, and reduced digestive dissociation. Compared with the control group, the total release of free amino acids decreased by 22.0%-34.4%, significantly reducing the digestive dissociation. Especially at the gastric stage, hydrolysis was inhibited by as much as 26.7%. During fecal fermentation, the complexes significantly promoted the production of short-chain fatty acids (SCFAs). Specifically, the ZLEP-YBG complex increased total SCFA and BCFA production by 55.6% and 32.7%, respectively, compared to the LEP. Microbiota and metabolomic analyses revealed Bacillota as a key regulator and activated pathways of purine, lipid, bile acid, and amino acid metabolism. Overall, this study deciphers the fundamental significance of protein-polysaccharide interactions, demonstrating that LEP-βG complexes exhibit robust prebiotic potential. These findings provide a compelling rationale for their application as high-value ingredients in the functional food industry.