不同酶类提取米糠蛋白的研究

Extracting Rice Bran Protein with Different Enzymes

我国米糠资源丰富 ,米糠蛋白的营养价值高。本文采用不同酶类提取米糠蛋白 ,比较蛋白收率 ,从中选出最佳水解用酶及确定酶用量。不同的酶水解米糠有不同的作用方式。本文对水解米糠所用的细胞破壁酶类和蛋白酶类进行选择 ,以蛋白收率为指标 ,水解度为参考指标 ,比较各种酶水解米糠制蛋白的效果 ,认为纤维素酶和复合蛋白酶水解效果较好 ,蛋白收率分别达 5 4.75 %和 5 8.93% ,因此选择这两种酶为水解用酶。分别对纤维素酶、复合蛋白酶的水解效果进行分析。在 pH、温度为各酶最适条件 ,水解时间、底物浓度相同的条件下 ,采用酶添加量的单因素试验 ,选择各酶的最适用量并比较在最适添加量的情况下其蛋白收率。结果当纤维素酶添加量为 [E]/[S]=2 %时 ,蛋白收率达最高为 5 6 .12 % ;复合蛋白酶添加量为 [E]/[S]pro =2 %时 ,蛋白收率达最高为 6 2 .0 4 %。

Different enzymes were used for extracting rice bran protein.The optimum enzyme was selected and the optimum enzyme concentration was determined by comparing the nitrogen recovery.The broken kernel enzymes and proteases were compared in the process of preparing rice bran protein.According to the nitrogen recovery and degree of hydrolysis,cellulase and protamax were selected and the nitrogen recovery was 54.75% and 58.93% respectively. Cellulase and protamax were separately used to hydrolysis rice bran under the optimum temperature,pH,and the same reaction time and substrate concentration.Single factor tests were conducted to determine the optimum enzyme concentration of every enzyme.The results showed that while cellulase concentration was [E]/[S]=2%、protamax concentration was [E]/[S] pro =5%,the relevant nitrogen recovery was 56.12% and 62.04%,respectively.