Identification of antioxidant peptides from protein hydrolysates of scallop (Patinopecten yessoensis) female gonads

Abstract

Scallop (Patinopecten yessoensis) female gonad hydrolysates (SFGHs) were obtained by using neutrase. The resulting hydrolysates possessed DPPH radical scavenging activity, ferrous ion-chelating ability, and reducing power with IC50 or AC0.5 values of 9.44, 0.94, and 5.88 mg/mL, respectively. SFGHs contained nearly 80 % of fractions with molecular weight around 250–5000 Da, and antioxidant-related amino acid residues in SFGHs reached to more than 30 %. Six fractions were separated from SFGHs on a Sephadex G-25 column, and one of the fractions with the highest DPPH radical scavenging activity was further analyzed by ESI-MS/MS, and a tetrapeptide His-Met-Ser-Tyr (536 Da) and a pentapeptide Pro-Glu-Ala-Ser-Tyr (565 Da) were identified. Both peptides showed hydroxyl radical scavenging activities with IC50 values of 3.6 and 16.8 mM, respectively, by electron spin resonance method. These results imply that peptides derived from scallop female gonads are potent antioxidants and may be utilized as functional ingredients in food systems.