Purification and characterization of a natural antioxidant peptide from fertilized eggs

Fertilized hen eggs are traditionally considered as dietary supplements in many Asian countries. This work aimed to obtain information on antioxidant peptides derived from fertilized eggs. Antioxidant activities were evaluated by measuring reducing power, DPPH radical scavenging activity and inhibition of pyrogallol autoxidation. During 15 days of incubation, the antioxidant activity of peptides increased with increasing incubation time. The peptides on day 15 were employed for isolation of antioxidant peptide. An antioxidant peptide, HLFGPPGKKDPV (MW: 1291.51 Da), was purified by consecutive chromatographic methods. The purified peptide was a novel peptide corresponding to the fragment 302-313 of ovotransferrin. The conformational prediction and Fourier transform infrared spectroscopy suggested that the peptide existed in β-sheet. Furthermore, the peptide showed an inhibition ratio of 60.20% on linoleic acid autoxidation and an inhibitory effect on ABTS radicals (IC50: 312 μM). These results suggested that fertilized eggs could be explored as a source of antioxidant peptides.