Isolation and identification of antioxidative peptides from pilot‐scale black‐bone silky fowl (Gallus gallus domesticus Brisson) muscle oligopeptides

BACKGROUND: A pilot-scale production was developed to produce oligopeptide powder from black-bone silky fowl (Gallus gallus domesticus Brisson) muscle (BSFP) by two-step enzymatic hydrolysis and multistage separation. The resultant BSFP was assessed for antioxidant activities against four free radicals (hydroxyl, 1,1-dipheny-2-picrylhydrazyl (DPPH), superoxide and peroxyl) and against the peroxidation of linoleic acid in a lipid peroxidation model system. After separation by reversed-phase high-performance liquid chromatography (RP-HPLC), five major fractions of BSFP were tested for DPPH radical scavenging activity and subjected to mass spectrometry to identify the active peptides. RESULTS: BSFP showed potential antioxidant activity in four assay systems. Three RP-HPLC fractions produced higher antioxidant effect than BSFP, with Fraction 4 showing the strongest activity. A total of 18 peptides were identified, and two peptides - Leu-Trp-Arg and Asn-Met - had strong scavenging activity, with IC50 values of 2.28 ± 0.05 and 4.65 ± 0.09 mg mL(-1) , respectively. Asn-Met is a novel antioxidative peptide that has not been previously reported. CONCLUSIONS: The results showed that the pilot-scale production of BSFP was a practical way to produce peptides with high value and potential antioxidant activity. BSFP and its antioxidative peptides can be a source of natural antioxidant and used as a food additive.