不同蛋白酶水解小米分离蛋白工艺

The Hydrolysis of Millet Protein by Different Proteases

以小米蛋白粉为原料,使用胃蛋白酶和碱性蛋白酶进行水解反应,用邻苯二甲醛法(OPA法)测定水解度,得到小米蛋白水解最佳时间,在此时间范围内进行单因素试验优化小米蛋白粉在不同底物浓度、温度和pH下胃蛋白酶和碱性蛋白酶的水解条件,通过聚丙烯酰胺凝胶电泳法观察水解过程中肽段变化,制备高水解度小米蛋白。结果表明,采用胃蛋白酶水解浓度1%蛋白时,底物浓度[E]/[S]=10%, pH 2,温度35℃水解1 h水解度最大;采用碱性蛋白酶水解浓度1%蛋白时,底物浓度[E]/[S]=10%, pH 9,温度45℃水解1 h水解度最大;由聚丙烯酰胺凝胶电泳图谱可以看出肽段逐渐水解的过程。

Using millet protein powder as raw material, using pepsin and alkaline protease to carry out hydrolysis reaction, the degree of hydrolysis was determined by o-phthalaldehyde method(OPA method), and the optimal time for protein hydrolysis of millet was obtained. The single factor experiment was optimized in this time range to optimize the hydrolysis condition of pepsin and alkaline protease in millet protein powder at different substrate concentrations, temperatures and pH. Polyacrylamide gel electrophoresis was used to observe the changes of peptides during hydrolysis reaction, so as to prepare millet protein with high hydrolysis degree. The results showed that using pepsin hydrolyze the protein at a concentration of 1%, the substrate concentration [E]/[S]=10%, pH2, and the hydrolysis was the highest at 35 ℃ for 1 h;Using the alkaline protease hydrolyze the protein at a concentration of 1%, the substrate concentration [E]/[S]=10%, pH 9, the temperature 45 ℃ hydrolysis 1 h, and the largest hydrolysis degree was arrived. The process of peptide hydrolysis could be observed by polyacrylamide gel electrophoresis.