绿豆抗氧化肽的酶法制备及其抗氧化活性

Enzymatic Preparation of Mung Bean Antioxidant Peptides and Antioxidant Activity Investigation

为提高绿豆淀粉生产过程中产生的废弃物绿豆蛋白的资源利用率,研究了酶法制备绿豆抗氧化肽的最佳条件,并探究其抗氧化活性。通过选用不同蛋白酶及其复合酶,对绿豆蛋白进行水解,综合考虑反应时间、加酶量等因素,对酶解反应进行优化。通过体外抗氧化实验对水解制得的多肽溶液进行抗氧化能力检测,最终确立了最佳的反应条件,具体如下:选用中性蛋白酶进行酶解,底物质量分数3%,酶解时间3 h,加酶量质量分数2%,pH 7,温度50℃。按照该条件所制得的绿豆多肽溶液,质量浓度为5 mg/mL时,DPPH自由基清除率可达(91.58±2.44)%,同时还具有较强的还原能力。经凝胶层析柱分离纯化后得到5个分离组分,其中小分子肽段组分5的抗氧化能力最强,高于其他大分子肽段以及未分离多肽。

In order to improve the resource utilization of mung bean protein,the waste produced in the mung bean starch production,the optimal conditions for preparing mung bean antioxidant peptides by enzymatic method were studied,and their antioxidant activity was also investigated.The enzymatic hydrolysis of mung bean protein was optimized by different proteases or their complex enzymes,with other factors examined including the reaction time and the enzyme amount.The antioxidant capacity of the hydrolyzed polypeptide was tested by in vitro antioxidant experiment.The optimal reaction conditions were finally established as follows:2%of neutral protease and 3%of substrate were used for 3 h hydrolysis at pH 7 and 50℃.The resulted mung bean peptide solution had a DPPH free radical scavenging rate of(91.58±2.44)%with a mass concentration of 5 mg/mL,showing strong reducing ability.Five separated fractions were obtained by purification using gel chromatography column. The small molecule peptide component 5 had the strongest antioxidant capacity, which was higher than other large molecule peptides and unseparated peptides.