title: Towards rice bran protein utilization: In silico insight on the role of oryzacystatins in biologically-active peptide production.
abstract: Rice bran proteins (RBP) have been demonstrated to harbour biologically active peptides, which can be released by proteases and applied in human health promotion. In this study, the roles of rice bran cysteine protease inhibitors, oryzacystatins, were considered for efficient production of bioactive peptides from RBP. In silico evidence demonstrates that aspartate protease (pepsin at pH>2) and metalloproteinase (thermolysin) have strong prospects for use in simultaneously cleaving the QXVXGX motif of oryzacystatins, which can lead to their inactivation, and in releasing bioactive sequences from the protease inhibitors. The cleaved bioactive peptides are known to possess activities that can be applied in the management of hypertension, oxidative stress, type 2 diabetes mellitus and other aberrant cellular processes. Moreover, several potentially bioactive di- and tripeptides were identified in oryzacystatin peptide pools. This study provides an important consideration and a direction that can lead to efficient release of bioactive peptides from rice bran proteins for functional food applications.
authors.affiliation: Health and Bioproducts Research Laboratory, Department of Environmental Sciences, Faculty of Agriculture, Dalhousie University, Truro, Nova Scotia B2N 5E3, Canada. Electronic address: cudenigwe@dal.ca.
authors.forename: Chibuike C
authors.initials: CC
authors.lastname: Udenigwe
mesh_terms: D000595:Amino Acid Sequence; D003198:Computer Simulation; D015891:Cystatins / Q000737:chemistry / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D012275:Oryza / Q000737:chemistry / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D015891:Cystatins; D015853:Cysteine Proteinase Inhibitors; D010455:Peptides; D010940:Plant Proteins
keywords: Bioactive peptides; In silico analysis; Oryzacystatin; Protease inhibitors; Rice bran proteins; Value addition