a b s t r a c t
Corn gluten meal is a major co-product of corn wet milling. Corn gluten meal was hydrolyzed with
Alcalase, Flavourzyme, Alcalase + Flavourzyme and Flavourzyme + Alcalase. At the substrate concentration of 10%, corn protein hydrolysate catalyzed by Alcalase had a degree of hydrolysis of 17.83%, which
was higher than that by Flavourzyme (3.65%). The hydrolysate catalyzed by Alcalase + Flavourzyme
exhibited better antioxidant activities and was further purified. Three novel antioxidant peptides were
purified by a series of chromatographic techniques. Sequences of the three peptides were identified as
Cys-Ser-Gln-Ala-Pro-Leu-Ala, Tyr-Pro-Lys-Leu-Ala-Pro-Asn-Glu and Tyr-Pro-Gln-Leu-Leu-Pro-Asn-Glu,
respectively. Among the three peptides, Cys-Ser-Gln-Ala-Pro-Leu-Ala exhibited good reducing power
and excellent scavenging capacities for DPPH radical and superoxide anion radical, with IC50 values of
0.116 and 0.39 mg/ml, respectively. The results from our study indicate antioxidant potency of corn
protein hydrolysates and peptides separated from corn gluten meal and can provide basic understanding
for the application of corn protein hydrolysates as natural antioxidants.