Mechanistic Insights\ninto Lignin’s Inhibition\nof Gluten Digestibility: Evidence from In Vitro Static Digestion

This study investigates the inhibitory\neffects of lignin\non gluten\ndigestibility and elucidates the underlying mechanism using static\nin vitro digestion protocols involving pepsin and pancreatin. Gluten\ndigestibility was evaluated based on the degree of protein hydrolysis\n(DH), peptides’ profile, and free amino acids (AAs) content.\nThe interactions between lignin and gluten under digestive conditions\nand their impact on proteolytic enzyme activities were examined through\nvarious analytical techniques, including scanning electron microscopy\n(SEM), viscosity measurements, ζ-potential analysis, and enzyme\nkinetics. Results reveal that lignin significantly impairs gluten\ndigestibility by inducing the formation of protein aggregates, leading\nto distinct intermediate peptides and reduced levels of key AAs such\nas aspartic acid, phenylalanine, proline, and histidine. These findings\noffer valuable insights into gluten-lignin interactions and highlight\nlignin’s potential applications in the food industry, particularly\nas a functional additive to modulate nutrient digestibility.