In vitro evaluation of the anti-digestion and antioxidant effects of grape seed procyanidins according to their degrees of polymerization

Abstract

Few studies have evaluated the anti-digestion effects of grape seed procyanidins (GSPs) compared to their strong anti-oxidant activities according to different degrees of polymerization (DPs). Additionally, the effects of GSPs with different DPs on the binding sites of digestive enzymes are unexplored. In this work, the anti-digestive and anti-oxidant activity of GSPs with different DPs were verified and compared. Anti-digestive activity assays were conducted on key digestive enzymes. Although all procyanidins fractions possessed antioxidant activity as expected, there was no significant difference in the antioxidant activity among procyanidins with different DPs. In contrast, the anti-digestive activity of the fractions increased significantly as the DP increased. Meanwhile, molecular docking provided a putative mechanism of anti-digestion, and GSPs can block the enzyme sites by hydrogen interactions, hydrophobic interactions and electrostatic interactions. These results indicated that the higher-molecular-weight procyanidins had equal or lower antioxidant activity and a greater anti-digestion effect than lower-molecular-weight procyanidins.