将胃蛋白酶加至CTAB(十六烷基三甲基溴化铵)/环己烷/正辛醇反胶束体系中得到固定化胃蛋白酶,研究了反胶束含水率、乙醇体积分数对固定化胃蛋白酶活力的影响,并对固定化胃蛋白酶和游离胃蛋白酶的催化性质进行了比较研究.结果表明,反胶束含水率为12％、乙醇体积分数为30％时,固定化胃蛋白酶的活力达到最佳；固定化胃蛋白酶和游离胃蛋白酶的酶促反应最适温度分别为50℃和40℃、最适Ca2+浓度分别为0.02 mol·L-1和0.01mol· L-1;对酪蛋白的米氏常数Km分别为1.22×10-4 mol·L-1和1.29×10-4 mol·L-1.固定化胃蛋白酶较游离胃蛋白酶具有更高的酶活力、更好的热稳定性和储存稳定性.%Pepsin was solubilized in reverse micelles of CTAB(cetyltrimethylammonium bromide) in cyclo-hexane with octanol as co-surfactant. The effects of water content and ethanol volume fraction of reverse micells on immobilized pepsin activity were studied. And the catalytic properties of free and immobilized pepsin were investigated. The results indicated that the enzymatic activity of immobilized pepsin was the best when water content was 12%, ethanol volume fraction was 30%; the optimum temperature of immobilized and free pepsin was 50 ℃ and 40 ℃ ,the optimum Ca2+ concentration was 0. 02 mol · L-1 and 0. 01 mol · L-1 ,the Km was 1. 22× 10-4 mol · L-1 and 1. 29 × 10-4 mol · L-1, respectively. The enzymatic activity, thermal stability and storage stability of immobilized pepsin were superior to those of free pepsin.
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