Formation of bioactive peptides during simulated gastrointestinal digestion is affected by αs1-casein polymorphism in buffalo milk

Abstract

The polymorphism of buffalo αs1-casein has been reported, but little is known about their effect on the biological properties. The objective of this study was to investigate the effect of αs1-casein polymorphism on the digestive properties and bioactivities of buffalo milk protein in simulated gastrointestinal digestion. In this study, two variants of αs1-casein, with one amino acid substitution of Leu193 (AA) → Ser193 (BB), were used. Under acidic gastric conditions, the particle size of αs1-casein variant BB was smaller and showed higher digestibility compared to variant AA. A total of 154 and 149 peptides were identified, respectively, from simulated gastrointestinal digestion of variants AA and BB; of three peptides have been previously reported to exert ACE-inhibition, anticancer, antioxidant, and anxiolytic activities. Our study demonstrated that αs1-casein polymorphism affects the digestive properties and the formation of bioactive peptides.