3种大米蛋白肽的制备及其抗氧化活性比较

Preparation of three rice protein peptides and comparison of antioxidant activities

为研究不同品种大米蛋白肽的品质特性,在采用碱式酸沉法提取大米蛋白的基础上,合理酶解制备大米蛋白肽,并以超氧自由基(O_2~—)、羟基自由基(OH~—)、DPPH自由基(DPPH·)清除率为指标,比较不同大米蛋白肽的水解度和抗氧化活性。结果表明,3种大米蛋白肽的水解度差异显著(P<0.05),由高到低依次为籼米>粳米>糯米。3种大米蛋白肽的半数自由基清除率(IC_(50))具有明显差异(P<0.05),其中籼米蛋白肽清除半数DPPH·自由基、O_2~—自由基、OH~—自由基的IC_(50)值最低,抗氧化活性最高,而糯米蛋白肽清除半数自由基的IC_(50)值远大于籼米、粳米蛋白肽,抗氧化活性最低。综合分析,籼米和粳米更适宜进行大米抗氧化肽的开发和利用。

In order to study the quality characteristics of different rice protein peptides, the paper extracted rice protein with alkaline and acid precipitation method fistly, rice protein peptide were prepared by rational enzymatic hydrolysis based on rice protein. Use clearance rate of superoxide radical (O2 ^-), hydroxyl radical (OH^-), DPPH (DPPH·) as the indicators to compare the degree of hydrolysis and antioxidant activity of different rice protein peptides. Results showed that the degree of hydrolysis had a significant difference in three rice protein peptide (P<0.05), from high to low, they were indica rice>japonica rice>glutinous rice. The half free radical clearance (IC50) had a significant difference in three rice protein peptides (P<0.05), Indica rice protein peptides had the lowest IC50 values of half superoxide radical, hydroxyl radical and DPPH radical, it’s antioxidant activity was the highest. But the IC50 value of scavenging free radicals of glutinous rice peptides was far greater than that of indica rice and japonica rice protein peptides, therefore, glutinous rice peptides had the lowest antioxidant activity. Comprehensively, indica rice and japonica rice were more suitable for the development and utilization of rice antioxidant peptides.