An antioxidant peptide produced by autolysis reactions from wheat germ
Wheat germ was incubated in a buffer solution of sodium citrate and dibasic sodium phosphate and its proteins were hydrolyzed by endogenous proteases to produce peptides. A peptide with high antioxidant activity was purified using ultrafiltration, Sephadex G-25 gel filtration column and consecutive chromatographic methods. The purified peptide was identified as Val-His-His-His (520.66 m/z) using reversed-phase high performance liquid chromatography (RP-HPLC) connected online to an electrospray ionization mass spectrometry. This antioxidant peptide showed high reducing power per unit, hydroxyl radical scavenging ratio and Cu2+ chelating ability. This study provides an economical and convenient method to isolate bioactive peptides from wheat germ.
Key words: Antioxidant peptide, wheat germ, autolysis.