Purification of antioxidative peptide from peptic hydrolysates of Mideodeok (Styela clava) flesh tissue

In this study, an antioxidative peptide was obtained by hydrolyzation of mideodeok (Styela clava ) flesh tissue with various proteases and purified through gel filtration chromatography and reverse phage-HPLC (RPHPLC), and then antioxidant activity was investigated using electron spin resonance (ESR) spectrometer. Among the enzymatic hydrolysates, the peptic hydrolysate exhibited the highest antioxidant activity, and a strong antioxidant peptide was purified from the hydrolysate. The peptide sequence, Leu-Trp-His-Thr-His (692.2 Da), was identified by quardruple time-of-flight electrospray ionization (QTOF ESI)-MS. This antioxidative peptide strongly scavenged peroxyl radical with the IC 50 value of 39.4 μM.