牦牛乳酪蛋白水解制备DPP-IV抑制肽的蛋白酶发掘及其酶解工艺优化

Proteases for preparation of DPP-IV inhibitory peptide from yak milk casein and process optimization

发掘制备牦牛乳酪蛋白二肽基肽酶-IV(dipeptidyl peptidase-IV,DPP-IV)抑制肽的蛋白酶,并对其酶解工艺进行优化。首先对牦牛乳酪蛋白进行模拟酶切筛选蛋白酶,然后开展单酶和多酶组合水解效果研究。结果表明,制备DPP-IV抑制肽的最佳酶组合为碱性蛋白酶、木瓜蛋白酶和菠萝蛋白酶,最佳酶解工艺为超声温度64℃、超声功率460 W、超声时间82 min,碱性蛋白酶、木瓜蛋白酶和菠萝蛋白酶依次酶解0.5 h,加酶量3000 U/g,酪蛋白水解物DPP-IV抑制率为(67.05±0.79)%,水解度为(30.57±0.72)%。结果表明,将组合酶水解联合超声预处理方法应用于酶解牦牛乳酪蛋白,可获得高活性DPP-IV抑制肽。

The objective of this study was to select proteases for preparation of DPP-IV inhibitory peptide from yak milk casein and optimize the enzymatic process.The hydrolytic proteases were screened by simulated enzymatic digestion of yak milk casein,and then single and multiple enzyme hydrolysis were carried out.The results showed that the best enzyme combination for the preparation of DPP-IV inhibitory peptide was alkaline protease,papain,and bromelain.The optimal enzymatic process for the preparation of DPP-IV inhibitory peptide was 64℃,460 W of ultrasonic power,82 min of ultrasonic,0.5 h hydrolysis of alkaline protease,papain and bromelain with 3000 U/g in turn.DPP-IV inhibition rate and hydrolysis degree of the final hydrolysate were(67.05±0.79)%and(30.57±0.72)%,respectively.The results indicated that the multiple enzyme hydrolysis combined with ultrasonic pretreatment could be applied to the hydrolysis of yak milk casein to obtain the DPP-IV inhibitory peptide with high active.