Abstract:

Defatted zein was hydrolyzed by proteolysis with protease. The hydrolysate was refined and freezedried into powder. The resulting hydrolysate was further purified by means of gel filtration, ion exchange chromatography and HPLC. With α-tocopherol as the positive control, the antioxidant abilities of corn peptide and its separated fractions were examined for their effects of scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, dosedependent manner was included. The data reveal that corn peptide and its separated fractions exhibited a potent effect of scavenging DPPH. The most active fraction from the active peptide was fraction 2 separated by CM cation exchange chromatography. Its scavenging effect is positively related to its concentration and the reaction time. The molecularmass distributions of the fraction 2 are mostly in a range from 400~700.

Key words: corn active peptide, separation and purification, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, scavenging effect