title: Isolation and structural elucidation of antioxidant peptides from oyster (Saccostrea cucullata) protein hydrolysate.
abstract: Protein derived from the oyster (Saccostrea cucullata) was hydrolyzed using protease from Bacillus cereus SU12 for isolation of antioxidant peptides. The oyster hydrolysate exhibited a strong antioxidant potential in DPPH (85.7±0.37%) followed by Hydrogen peroxide radical scavenging activity (81.6±0.3%), Hydroxyl radical-scavenging activity (79.32±0.6%), Reducing power assay (2.63±0.2 OD at 700nm). Due to the high antioxidant potential, hydrolysate was fractionated in Sephadex G-25 gel filtration chromatography. The active peptide fraction was further purified by UPLC-MS. Totally 7 antioxidant peptides were collected. Among 7 peptides (SCAP 1-7), 3 peptides (SCAP 1, 3 and 7) had highest scavenging ability on DPPH radicals. The amino acid sequence and molecular mass of purified antioxidant peptides (SCAP1, SCAP3 and SCAP7) were determined by Q-TOF ESI mass spectroscopy and structures of the peptides were Leu-Ala-Asn-Ala-Lys (MW=515.29Da), Pro-Ser-Leu-Val-Gly-Arg-Pro-Pro-Val-Gly-Lys-Leu-Thr-Leu (MW=1432.89Da) and Val-Lys-Val-Leu-Leu-Glu-His-Pro-Val-Leu (MW=1145.75Da), respectively. The unique amino acid composition and sequence in the peptides might play an important role in expression of their antioxidant activity. The results of this study suggest that oyster protein hydrolysate is good source of natural antioxidants.
authors.forename: S
authors.initials: S
authors.lastname: Umayaparvathi
authors.forename: S
authors.initials: S
authors.lastname: Meenakshi
authors.forename: V
authors.initials: V
authors.lastname: Vimalraj
authors.forename: M
authors.initials: M
authors.lastname: Arumugam
authors.affiliation: Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai - 608 502, Tamil Nadu, India. shanuma1987@gmail.com.
authors.forename: T
authors.initials: T
authors.lastname: Balasubramanian
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification; D001409:Bacillus cereus / Q000737:chemistry / Q000201:enzymology; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors*; D006861:Hydrogen Peroxide / Q000037:antagonists & inhibitors*; D006868:Hydrolysis; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry* / Q000302:isolation & purification; D010125:Ostreidae / Q000737:chemistry*; D010447:Peptide Hydrolases / Q000737:chemistry / Q000302:isolation & purification; D010851:Picrates / Q000037:antagonists & inhibitors*; D011506:Proteins / Q000737:chemistry* / Q000302:isolation & purification; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D009842:Oligopeptides; D010851:Picrates; D011506:Proteins; D006861:Hydrogen Peroxide; C004931:1,1-diphenyl-2-picrylhydrazyl; D010447:Peptide Hydrolases