Interaction between dietary polyphenol and proteins including digestive enzymes may result in reduced digestibility of food macronutrients, thus lowering absorption of nutrients that contributing to high energy accumu...Interaction between dietary polyphenol and proteins including digestive enzymes may result in reduced digestibility of food macronutrients, thus lowering absorption of nutrients that contributing to high energy accumulation in human body. The objective of this study was to investigate the effect of grape seed polyphenol extract （GSPE） on the digestibility of starch, food lipid and food protein by digestive enzymes such as u-amylase, lipase, pepsin and trypsin. The digestion of each substrate was conducted at the optimal pH and temperature of specific enzyme. Bread containing different amount of grape pomace was used as a real food model and its digestion was conducted under simulated digestion condition. Concentrations of reducing sugar, fatty acid and amino acids in enzyme digested mixtures were determined as indicators of starch, lipid and protein digestions, respectively. Results indicate that GSPE significantly inhibited the digestion of starch, cooking oil and casein, but did not inhibit digestion of whey protein and egg white protein. Instead, the digestion of egg white and whey protein by trypsin was moderately enhanced in the presence of GSPE. However, under simulated human digestion condition, the grape pomace in the bread significantly reduced the digestibility of bread starch and protein.展开更多
文摘Interaction between dietary polyphenol and proteins including digestive enzymes may result in reduced digestibility of food macronutrients, thus lowering absorption of nutrients that contributing to high energy accumulation in human body. The objective of this study was to investigate the effect of grape seed polyphenol extract （GSPE） on the digestibility of starch, food lipid and food protein by digestive enzymes such as u-amylase, lipase, pepsin and trypsin. The digestion of each substrate was conducted at the optimal pH and temperature of specific enzyme. Bread containing different amount of grape pomace was used as a real food model and its digestion was conducted under simulated digestion condition. Concentrations of reducing sugar, fatty acid and amino acids in enzyme digested mixtures were determined as indicators of starch, lipid and protein digestions, respectively. Results indicate that GSPE significantly inhibited the digestion of starch, cooking oil and casein, but did not inhibit digestion of whey protein and egg white protein. Instead, the digestion of egg white and whey protein by trypsin was moderately enhanced in the presence of GSPE. However, under simulated human digestion condition, the grape pomace in the bread significantly reduced the digestibility of bread starch and protein.
