大米蛋白的酶水解机制研究——Ⅰ酶反应进程及酶在反应体系中的分配

Mechanism of Enzymetic Hydrolysis of Rice Protein (Ⅰ):Hydrolysis Process and Distribution of Enzyme in System

通过不同酶浓度和底物浓度下可溶出蛋白的分析表明,大米蛋白浓度约为8%、加酶量30AU/kg以下、反应时间150min以内是研究大米蛋白水解规律较合适的条件。水解过程中加酶量为30AU/kg的酶解物DH/蛋白质溶解度比值高于12AU/kg时的比值,且大分子组分(分子量为26100ku)的相对含量较低,而小分子组分(分子量为1350ku和220～660ku)的含量较高,说明反应体系中加入较多的蛋白酶时分配于水解已溶蛋白的酶比例增高。

According to the yield of soluble rice protein in rice protein enzymetic hydrolysis, the suitable condi- tion for studying the enzymolysis mechanism is as follows： concentration of rice protein 8%, enzyme/protein ratio （E/S） 30 AU/kg, and reaction time 150 rain. Comparing the enzymolysis results at E/S 30 AU/kg with those at E/ S 12 AU/kg, the degree of hydrolysis is high, the content of big relative molecular mass is lower （ Molecular weight. 26 100ku） and the content of small relative molecular mass （Molecular weight. 1 350ku and 220 - 660ku） is higher. It is indicated that with increase of E/S in the enzymolysis system, the proportion of enzyme distributed in the supernatant is increased.