Interactions of digestive enzymes and milk proteins with tea catechins at gastric and intestinal pH

摘要: Summary The interactions of digestive enzymes (pepsin, pancreatin) and milk proteins (β-casein, β-lactoglobulin (β-Lg)) with (−)-epigallocatechin gallate (EGCG), (EGC) (−)-epicatechin (EC) at gastric intestinal pH were investigated by fluorescence spectroscopy. The results indicated that in the environment, all three tea catechins showed binding affinities descending order strength β-casein first, followed β-Lg then pepsin. highest affinity was observed for EGCG–β-casein, a constant (KA) 2.502(±0.201) × 105 m−1. In strengths EGCG EGC β-Lg > pancreatin > β-casein; EC, > β-Lg > pancreatin. combination EGCG–β-Lg had strongest affinity, KA 14.300(±0.997) × 105 m−1. Thermodynamic analysis revealed complexed via different hydrophilic hydrophobic depending on digestion environments types catechins, enzymes.