Reactivity of Functional Food Substance in terms of Structure Analysis

Hypocholesterolemic peptide isolated from glycimin (11S protein) hydrolyzate by trypsin was purified and identified as LPYP and IAVPGEVA. To investigate the effects of phyiscal properties of side chains of the hypocholesterolemic activity, some of mutant peptides were designed and synthesized chemically. The structure related structures of each peptide were simulated and constructed and their conformations were observed by using spectropolarimeter. The hypocholesterolemic activities were monitored by assaying the inhibition of 3-hydroxy-3-methylglutaryl CoA reductase (HMG-CoA reductase) in vitro and by the determination of cholesterol content in mice serum. For LPYP derivatives, Hypocholesterolemic activity was lost when hydrophobic leucine residue at N-terminus was not so critical for maintaining hypocholesterolemic activity. For idealogical design of hypocholesterolemic peptides, the structure of HMG-CoA reductase are shown and inhibition mechanism of some peptides or inhibitors will be presented. For IAVPGEVA derivative inhibition of HMG-CoA reductase has been studied. For detail study of hypocholesterolemic activity, kinetic study of inhibition of peptides on HMG-CoA reductase and structural view of ligand binding should be investigated.