乳清蛋白降胆固醇肽的制备及活性研究

Preparation and activity of whey protein cholesterol-lowering peptide

为了得到高效降解胆固醇的乳清蛋白肽,对乳清蛋白(WPC80)进行蛋白酶水解,利用超滤浓缩,阴阳离子交换树脂纯化,探究活性肽对小鼠血液中胆固醇水平、甘油三酯水平、低密度脂蛋白胆固醇以及高密度脂蛋白胆固醇含量的影响。结果表明:采用胰蛋白酶+中性蛋白酶(酶量比4:1)双酶水解乳清蛋白获取的降胆固醇肽抑制率最大,为19.83%;经过超滤浓缩及阴阳离子交换树脂法纯化后活性肽抑制率提高到47.82%,肽总含量可达80.24%。同时该活性肽显著降低了小鼠血清总胆固醇水平(P<0.05),降低率达36.3%,具有显著降胆固醇的生理功效。

In order to obtain whey protein peptide which efficiently degrades cholesterol, this study carried out protease hydrolysis of whey protein(WPC80), concentrated by ultrafiltration, purified by anion-cation exchange resin, and explored the effect of the active peptide on cholesterol level in mice blood, glycerol trilaurate levels, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels. The results showed that the inhibition rate of cholesterol-lowering peptide obtained by hydrolysis of whey protein by trypsin+neutral protease(4:1 enzyme ratio) was 19.83%;it was purified by ultrafiltration and purification by anion-cation exchange resin. The peptide inhibition rate increased to 47.82%, and the total peptide content reached 80.24%. At the same time, the active peptide significantly reduced serum total cholesterol levels in mice(P<0.05), the reduction rate was 36.3%, with a significant cholesterol-lowering physiological effect.