In vivo antioxidative ability of enzymatic hydrolysates from zein

The antioxidative ability of protease hydrolysates of a deamidated zein denatured in a solution of 8M urea containing 1% ammonia was studied in vivo. Five-weeks age rats were administered the diets containing each deamidated zein, Proleather hydrolysates of the deamidated zein, the amino acid mixture simulating the enzymatic hydrolysates, and casein (control diet) for 4 weeks. TBARS values and related enzyme activities were assayed. The following results were obtained. The blood and hepatic TBARS level of the hydrolysates group was significantly lower, but those of the deamidated zein group and the amino acid mixture group were significantly higher than that of the control group. The activities of glutathione peroxidase (GSH. Px), catalase (CAT), superoxide dismutase (SOD) were significantly higher, but glutathione S-transferase (GST) was significantly lower in the blood of the hydrolysates group compared with the control group. The activities of GSH. Px, CAT were significantly higher in the liver of the hydrolysates group compared with the control group. There were no significant differences in the SOD and GST activity of the liver between the hydrolysates group and the control group.