Structure-activity studies of protease activating, lipase inhibiting, bile acid binding and cholesterol-lowering effects of pre-screened cumin seed bioactive peptides

The objective of this study was to evaluate the in vitro physiological properties of prescreened cumin seed peptides (CSPs) based on in vitro and in silico studies. Results showed that CSPs were capable of increasing the protein digestibility up to 400%. Apart from that, CSP1 and CSP2 showed >50% inhibition of pancreatic lipase activity. These peptides also exerted a similar or greater affinity to bind bile acid than cholestyramine, in addition to giving inhibitory effect (up to 80%) in the formation of cholesterol micelle. Based on the structure activity relationship studies, the results have postulated that the interaction of peptides at non-catalytic region induced allosteric effects to enhance the pepsin proteolytic activity; the direct contact of the peptide with lipase active sites rendered inhibitory action; and the binding between peptide and bile acids was relied on the hydrophilic and hydrophobic interactions. (C) 2016 Elsevier Ltd. All rights reserved.