Soybeans are known as a promising source of bioactive peptides.However,knowledge on the antioxidant behaviors of soybean protein hydrolysate(SPH)in the human intestinal epithelium is limited.In this study,SPH was prep...Soybeans are known as a promising source of bioactive peptides.However,knowledge on the antioxidant behaviors of soybean protein hydrolysate(SPH)in the human intestinal epithelium is limited.In this study,SPH was prepared with Alcalase and subsequently ultrafiltered into four peptide fractions as SPH-I(<3 kDa),SPH-II(3~5 k Da),SPH-III(5~10 k Da)and SPH-IV(>10 kDa).The antioxidant properties of SPH and membrane fractions were investigated using different chemical assays and their protective effects against oxidative stress were evaluated using H2 O2-stressed human intestinal Caco-2 cells.Results showed that SPH-I exhibited the strongest 2,2-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging activity(IC50=2.56 mg/m L)and reducing capacity while SPH-III had the best metal ion-chelating activity(IC50=0.29 mg/m L).Both SPH and the peptide fractions dose-dependently suppressed intracellular reactive oxygen species(ROS)accumulation induced by H2O2 in Caco-2 cells,but the strongest inhibitory effect was observed for SPH-I.Amino acid(AA)results revealed that SPH-I was rich in hydrophobic and antioxidant AAs,which could contribute to its stronger antioxidant properties.Additionally,SPH-I protected Caco-2 cells from H2O2-induced oxidative stress via inhibiting lipid peroxidation and stimulating antioxidant enzyme activities.These results suggest that SPH-I and constitutive peptides can be beneficial ingredients with antioxidant properties and protective effects against ROS-mediated intestinal injury.展开更多
基金financially supported by the National Natural Science Foundation of China(No.31430067,31601475,31571876,and 31671807)the 13th Five-Year Plan(No.2016YFD0401402)
文摘Soybeans are known as a promising source of bioactive peptides.However,knowledge on the antioxidant behaviors of soybean protein hydrolysate(SPH)in the human intestinal epithelium is limited.In this study,SPH was prepared with Alcalase and subsequently ultrafiltered into four peptide fractions as SPH-I(<3 kDa),SPH-II(3~5 k Da),SPH-III(5~10 k Da)and SPH-IV(>10 kDa).The antioxidant properties of SPH and membrane fractions were investigated using different chemical assays and their protective effects against oxidative stress were evaluated using H2 O2-stressed human intestinal Caco-2 cells.Results showed that SPH-I exhibited the strongest 2,2-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging activity(IC50=2.56 mg/m L)and reducing capacity while SPH-III had the best metal ion-chelating activity(IC50=0.29 mg/m L).Both SPH and the peptide fractions dose-dependently suppressed intracellular reactive oxygen species(ROS)accumulation induced by H2O2 in Caco-2 cells,but the strongest inhibitory effect was observed for SPH-I.Amino acid(AA)results revealed that SPH-I was rich in hydrophobic and antioxidant AAs,which could contribute to its stronger antioxidant properties.Additionally,SPH-I protected Caco-2 cells from H2O2-induced oxidative stress via inhibiting lipid peroxidation and stimulating antioxidant enzyme activities.These results suggest that SPH-I and constitutive peptides can be beneficial ingredients with antioxidant properties and protective effects against ROS-mediated intestinal injury.
