Simulated in vitro gastrointestinal digestion of β-lactoglobulin treated by ultrasound: Detection of peptides profile and the antioxidant activity.

The influence of ultrasonic pretreatment on the release and antioxidant activity of potential antioxidant peptides after in-vitro simulated gastrointestinal digestion of β-lactoglobulin (BLG) were measured by HPLC-MS/MS, chemical and cellular-based assays. The gastrointestinal digest was fractionated into four fractions by Sephadex G-25 gel filtration column, and fractions showed a considerable ABTS· scavenging ability. The fraction with the strongest antioxidant activity was produced by ultrasonicated BLG after gastrointestinal digestion, which relies on ultrasonic-promoted proteolysis to produce many small-molecule antioxidant peptides.