Title:Isolation and Structural Elucidation of Antioxidant Peptides from Oyster (Saccostrea cucullata) Protein Hydrolysate
Volume: 21
Issue: 10
Author(s): Shanmugam Umayaparvathi, Selvaraju Meenakshi, Vinayagam Vimalraj, Muthuvel Arumugam and Thangavel Balasubramanian
Affiliation:
Keywords:
Antioxidant peptide, DPPH, electrospray ionization mass spectrometry, enzymatic hydrolysis, 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.
