title: Rice Bran Protein as a Potent Source of Antimelanogenic Peptides with Tyrosinase Inhibitory Activity.
abstract: Rice (Oryza sativa) is consumed as a staple food globally, and rice bran, the byproduct, is an unused biomass that is ultimately discarded as waste. Thus, in the present study, a technique for producing tyrosinase inhibitory peptides from rice bran protein (RBP) was developed. Simultaneous treatment of RBP with chymotrypsin and trypsin produced numerous peptides. Subsequently, six tyrosinase inhibitory peptides were isolated from the hydrolysate fractions in a multistep purification protocol, and their amino acid sequences were determined. Three of these peptides had a C-terminal tyrosine residue and exhibited significant inhibitory effects against tyrosinase-mediated monophenolase reactions. Furthermore, peptide CT-2 (Leu-Gln-Pro-Ser-His-Tyr) potently inhibited melanogenesis in mouse B16 melanoma cells without causing cytotoxicity, suggesting the potential of CT-2 as an agent for melanin-related skin disorder treatment. The present data indicate that RBP is a potent source of tyrosinase inhibitory peptides and that simultaneous treatment of RBP with chymotrypsin and trypsin efficiently produces these peptides.
authors.affiliation: Department of Materials Science and Technology, Faculty of Engineering, and ‡Graduate School of Science and Technology, Niigata University , Niigata 950-2181, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Ochiai
authors.affiliation: Department of Materials Science and Technology, Faculty of Engineering, and ‡Graduate School of Science and Technology, Niigata University , Niigata 950-2181, Japan.
authors.forename: Seiya
authors.initials: S
authors.lastname: Tanaka
authors.affiliation: Department of Materials Science and Technology, Faculty of Engineering, and ‡Graduate School of Science and Technology, Niigata University , Niigata 950-2181, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Department of Materials Science and Technology, Faculty of Engineering, and ‡Graduate School of Science and Technology, Niigata University , Niigata 950-2181, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Taniguchi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002918:Chymotrypsin / Q000378:metabolism; D004151:Dipeptides; D008543:Melanins / Q000032:analysis; D008546:Melanoma, Experimental / Q000188:drug therapy*; D051379:Mice; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D012275:Oryza / Q000737:chemistry*; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry; D014357:Trypsin / Q000378:metabolism
chemical_list: D004151:Dipeptides; D008543:Melanins; D010455:Peptides; C465982:prolyl-serine; D014442:Monophenol Monooxygenase; D002918:Chymotrypsin; D014357:Trypsin