【摘要】 系统研究了α-胰凝乳蛋白酶、木瓜蛋白酶、枯草杆菌蛋白酶和嗜热杆菌蛋白酶4种蛋白水解酶在一系列分子筛上的吸附固定.所用分子筛载体包括微孔分子筛:HY、NaY、NH4Y、MCM-22、Hβ沸石,改性Y沸石:HDAY、HNH4DAY以及介孔分子筛MCM-41.结果表明,不仅分子筛的结构与酶的性质对酶的固定化量与固定化酶的活性有重要影响,而且吸附固定化条件如缓冲液的pH值和酶的浓度等对酶的吸附固定化也有显著影响.在多数情况下,pH值为6时蛋白水解酶在分子筛上的吸附固定化的量较高,随着pH值进一步升高吸附量降低.探讨了蛋白水解酶与不同分子筛之间的相互作用,例如α-胰凝乳蛋白酶在Hβ沸石上吸附固定化量最高,而固定在MCM-22上的α-胰凝乳蛋白酶的活性最高,这显然与其吸附状态有关.更多还原

【Abstract】 The immobilization of four different proteases on a series of molecular sieves,including microporous HY,NaY,NH4Y,MCM-22,Hβ zeolites,modified Y zeolites HDAY,HNH4DAY,and mesoporous MCM-41,by adsorption was systematically investigated.The four proteases were α-chymotrypsin,papain,subtilisin,and thermoase (or its pure form thermolysin).The results showed that the enzyme loading amount and the activity of immobilized enzyme were significantly affected not only by the structures and textures of molecular sieves and the enzyme properties,but also by the adsorptive conditions such as buffer pH values and enzyme concentration.In most cases,the amount of protease loading on molecular sieves was relatively higher at pH 6.0,but declined with further increasing of pH values.The nature of the interaction between protease and molecular sieves is discussed.As for α-chymotrypsin,its loading amount on Hβ zeolites was found to be the highest,whereas the activity of α-chymotrypsin immobilized on MCM-22 was the highest,which is probably due to different adsorption states.更多还原