Purification and characterisation of an antioxidative peptide from enzymatic hydrolysates of duck processing by-products

Duck processing by-products were hydrolysed using eight proteases to produce an antioxidative peptide. Of the various hydrolysates produced, the pepsin extract exhibited the highest hydroxyl radical scavenging activity. The derived peptide was purified using high-performance liquid chromatography (HPLC) to identify any potent radical scavenging activity. The sequence of the antioxidative peptide obtained was identified as Asp-Val-Cys-Gly-Arg-Asp-Val-Asn-Gly-Tyr, with a molecular weight of 1096 Da. The IC₅₀ value of purified peptide for hydroxyl radical scavenging activity was 75 μg/ml as the measurement by an electron spin resonance (ESR) spectrometer. In addition, the purified peptide exhibited a protective effect on H₂O₂-induced DNA damage. These results indicate that the purified peptide possesses a potent antioxidative activity and protective effect of DNA against H₂O₂-induced oxidative damage.