玛咖多肽的制备及抗氧化活性研究

Study on preparation and antioxidant activity of Maca peptide

以水解度为考察指标,在单因素实验基础上,利用正交实验优化酶解玛咖粗蛋白制备玛咖多肽的工艺,同时通过·OH、DPPH·及O_2^-·清除实验研究提取过程中产生的玛咖醇提液以及在最适条件下制得的玛咖多肽的抗氧化活性,并对玛咖多肽进行氨基酸组成分析。结果表明,酶解玛咖粗蛋白的最适酶是碱性蛋白酶,酶解制备玛咖多肽的最适条件是酶解时间4 h、酶解p H为10.5、酶解温度55℃、加酶量1.6×10~4U/g,在此条件下,玛咖粗蛋白的水解度为(31.55%±0.74%)。稀释一倍的玛咖醇提液对各自由基清除率为最大,对DPPH自由基的清除率为94.44%,对·OH的清除率为85.05%,对O_2^-·清除率为53.85%。玛咖多肽对·OH、DPPH·及O_2^-·的IC_(50)值分别为0.85、0.44、0.86 mg/m L,且表现出一定的量效关系。另外,玛咖多肽中Tyr、His、Lys、Pro四种氨基酸含量为16.98%,其氨基酸组成与抗氧化活性存在一定关系。该结果说明玛咖醇提液及玛咖蛋白均具有一定的抗氧化活性。

The degree of hydrolysis used as response value, the enzymatic hydrolysis condition of Maca protein which prepare for Maea peptide was optimized with orthogonal test experiment, and · OH, DPPH and O2-· scavenging activities were tested for antioxidant activity evaluationThe results showed that the most suitable enzyme was alkaline protease, alkaline protease optimal preparation conditions of Maca peptide were as follow：time 4 h, pill0.5, temperature 55℃, the amount of enzyme 1.6 × 104 U/g. Under this condition, the preparation of Maca polypeptide hydrolysis was （31.55% ± 0.74% ）.Scavenging radicals ability of double dilution of maca alcohol was maxinmm, the scavenging rate of DPPH was 94.44% , the scavenging rate of ·OH was 85.05% ,the scavenging rate of O2-· was 53.85%.IC50 values of Maca peptide scavenged DPPH, ·OH and O2-· were 0.85, 0.44,0.86 mg/mL, and its antioxidant capacity increased with the concentration.In addition, the four amino acid compositions of Maca peptide：Tyr, his, Lys, Pro, their contents were 16.98%, the amino acid composition have a certain relationship with antioxidant activity.The results showed that both of Maea alcohol and Maca peptide have antioxidant activity.