黑豆多肽的制备及其对乙醇脱氢酶活性的影响研究

Research on the preparation of black beans polypeptide and its effect on the activity of alcohol dehydrogenase

目的制备黑豆多肽,研究其对乙醇脱氢酶（alcohol dehydrogenase,ADH）活性的影响。方法采用碱性蛋白酶与胰蛋白酶分步水解法制备黑豆多肽。用截留分子量分别为5000、3500、2000、1000 Da的透析袋将黑豆多肽分离成4个相对分子量的肽段,对不同相对分子量的黑豆多肽进行抗氧化能力以及体外醒酒活性实验。结果黑豆多肽在碱性蛋白酶与胰蛋白酶分步水解后的水解度达35.64%。不同分子量的黑豆多肽均具有对乙醇脱氢酶的激活作用和对羟自由基（·OH）的清除能力,且都随着黑豆多肽相对分子质量的减小而增强。相对分子质量在1000 Da以下的黑豆多肽对乙醇脱氢酶的激活率和羟自由基（·OH）的清除能力最强,分别达22.43%和24.39%。结论黑豆多肽具有较强的乙醇脱氢酶激活率,并且与黑豆蛋白质和其他来源的多肽相比,相对分子质量在500~2000 Da的黑豆多肽中亮氨酸和丙氨酸的含量较多,因此推测黑豆多肽具有较好的醒酒效果。

Objective To prepare black beans polypeptide and study its effect on the activity of alcohol dehydrogenase （ADH）.Methods The black beans polypeptide was prepared by step-by-step hydrolysis method of alkaline protease and trypsin. The black beans polypeptide was separated into 4 molecular segments with the dialysis bags of different intercept molecular weights which were 5000, 3500, 2000 and 1000 Da. The antioxidant activity and in vitro experiment of antialcoholism activity of the black beans polypeptides with different molecular weights were studied.ResultsThe degree of hydrolysis reached 35.64% after the hydrolysis of peptides with alkaline protease and trypsin. All the peptides of different molecular weights had the effect on the activation for alcohol dehydrogenase and the scavenging ability for hydroxyl radicals, and the above abilities increased with the decrease of relative molecular mass of black beans polypeptide. When the molecular weight was less than 1000 Da, the scavenging ability to hydroxy radical and the activation ability to ADH were the strongest, which reached 24.39% and 22.43%, respectively.Conclusion Black beans polypeptide has strong activity of ADH, and the content of leucine and alanine in black bean polypeptide with relative molecular weight between 500~2000 Da is higher than that of other peptides and black bean protein. Therefore, we can speculate that the black bean peptides have a good sobering effect.