Antioxidative activity and protective effect against ethanol-induced gastric mucosal damage of a potato protein hydrolysate.

Antioxidative activity and protective effect against ethanol-induced gastric mucosal damage of potato protein hydrolysate (potato peptides, Po-P) were studied in vitro and in vivo. The Po-P obtained by proteolysis with Amano P and pancreatin inhibited linoleic acid oxidation either by 83%, at its coexistent 0.005% in a ferric thiocyanate assay system or by 32% at its coexistent 0.0002% in a beta-carotene decolorization assay system. Meanwhile Po-P were orally administered to male Wistar rats at doses of 12.5-100 mg/kg of body weight (BW) 30 min prior to ethanol injection. Consequently the ethanol-induced gastric damage was significantly reduced in a dose-dependent manner in the Po-P administered rat. The highest effect was observed in the group dosed with 100 mg Po-P/kg BW; the inhibition ratio was 69.6%. The extent of antioxidation or protection against ethanol-induced gastritis was quite similar to those of the respective peptides from casein, corn protein and ovalbumin, suggesting that the potato protein hydrolysate could serve as a useful food ingredient in practical eating habits.