【摘要】 采用不同蛋白酶（碱性蛋白酶、中性蛋白酶、风味蛋白酶、木瓜蛋白酶和胰蛋白酶）在其最适温度和pH值下，以相同的酶底比（2 000 U/g）和料液比（40 g/L）分别水解米糠蛋白、大豆蛋白、乳清蛋白和酪蛋白。以α-葡萄糖苷酶抑制活性和水解度为评价指标筛选所得蛋白肽，结果表明中性蛋白酶水解酪蛋白所得蛋白肽具有最高的α-葡萄糖苷酶抑制活性(IC₅₀=0.79 mg/mL±0.21 mg/mL)。经超滤分级，分子质量为1～3 ku的酪蛋白肽（FCPs）的α-葡萄糖苷酶抑制活性最高(IC₅₀=0.40 mg/mL±0.10 mg/mL)。通过构建Caco-2单层细胞模型模拟人体小肠肠腔结构，发现未分级和分子质量为1～3 ku的酪蛋白肽可显著抑制小肠上皮细胞内α-葡萄糖苷酶的活性，进一步抑制小肠腔内麦芽糖的代谢和葡萄糖的吸收，且抑制效果好。通过测定正常小鼠餐后血糖的变化，发现1～3 ku酪蛋白肽可显著抑制餐后血糖的升高，对餐后糖代谢具有良好的调节作用。本研究确定了具有α-葡萄糖苷酶抑制活性酪蛋白肽的制备方法，并验证了其调节糖代谢作用，为丰富酪蛋白肽的降血糖生物活性、开发食源性降血糖功能食品提供了科学依据与新方向。更多还原

【Abstract】 In this study, various proteases（alkaline protease, neutral protease, flavored protease, papain, and trypsin）were used to hydrolyze rice bran protein, soy protein, whey protein, and casein at an equivalent enzyme substrate ratio（2 000 U/g） and feed-to-liquid ratio（40 g/L） under their respective optimal temperatures and pH conditions. The obtained peptides were assessed based on α-glucosidase inhibitory activity and degree of hydrolysis, revealing that peptides derived from casein hydrolysis by neutral protease demonstrated the highest α-glucosidase inhibitory activity(IC₅₀=0.79 mg/mL±0.21 mg/mL). Casein peptides with molecular weights of 1-3 ku（FCPs）, isolated through ultrafiltration, exhibited the highest α-glucosidase inhibitory activity(IC₅₀=0.40 mg/mL±0.10 mg/mL). Utilizing a Caco-2 monolayer cell model to simulate the structure of the human small intestinal lumen, both ungraded and 1-3 ku casein peptides significantly inhibited α-glucosidase activity in small intestinal epithelial cells, subsequently inhibiting maltose metabolism and glucose uptake in the small intestinal lumen. The inhibitory effect was more pronounced for 1-3 ku casein peptides. Assessment of postprandial glucose changes in normal mice revealed that 1-3 ku casein peptides significantly inhibited postprandial blood glucose elevation and demonstrated a beneficial regulatory effect on postprandial glucose metabolism. This investigation aimed to elucidate the preparation method for casein peptides exhibiting α-glucosidase inhibitory activity and subsequently validate their role in modulating glucose metabolism, thereby providing a scientific basis and new direction for enriching the hypoglycemic bioactivity of casein peptides and developing food-derived functional foods with hypoglycemic properties.更多还原