Protective effects of antioxidant egg-chalaza hydrolysates against chronic alcohol consumption-induced liver steatosis in mice

Reactive oxygen species (ROS) overproduction is highly related to some human chronic diseases. There are approximately 400 metric tons of chalazae produced yearly after the processing of the liquid-egg production, which are disposed of as waste. The objectives of this study were to look for the optimal production condition of antioxidant crude chalaza hydrolysates and evaluate the in vivo antioxidant capacity via a chronic alcohol consumption mouse model.Antioxidant crude chalaza hydrolysates (CCH-As) could be produced by protease A at 1:100 ratio (w/w) and 0.5 h hydrolytic period. After our analyses, CCH-As were rich in leucine, arginine, phenylalanine, valine, lysine and antioxidant dipeptides (anserine and carnosine), and the major molecular masses were lower than 15 kDa. Regarding protective effects of CCH-As against oxidative damage in alcoholic-liquid-diet-fed mice, alcohol-fed mice had lower (P0.05) liver antioxidant capacities, and higher (P0.05) liver lipid contents, serum lipid/liver damage indices and IL-1β/IL-6 values. CCH-A supplementation reversed (P0.05) liver antioxidant capacities and reduced (P0.05) serum/liver lipids in alcohol-fed mice, which may result from increased (P0.05) fecal lipid output, upregulated (P0.05) fatty acid β-oxidation and downregulated (P0.05) lipogenesis in the liver.Taken together, this CCH-A should benefit the liquid-egg industry, while also offering consumers a choice of healthy ingredients from animal sources. © 2018 Society of Chemical Industry.