离子交换树脂DOEX~ 50WX8固定化K.fragilis β-D-半乳糖苷酶  

K.fragilis β-D-galactosidase immobilization by adsorption in ionic exchange resin DOEX~ 50WX8 for milk lactose hydrolysis

作　　者：孟宪昉[1] 刘建福[2] 白正晨[1] 

机构地区：[1]天津商业大学理学院,天津300134 [2]天津商业大学生物技术与食品科学学院,天津市食品生物技术重点实验室,天津300134

出　　处：《食品科技》2014年第4期2-5,共4页Food Science and Technology

摘　　要：K.fragilisβ-D-半乳糖苷酶通过离子吸附固定在离子交换树脂DOEX50WX8上,用于催化牛乳中的乳糖水解。研究了pH、酶的初始浓度、时间等因素对酶固定化效率的影响,探讨了固定化酶的操作稳定性及其水解乳糖的效率。结果表明:在pH7.0、初始酶浓度10.0 mg/mL、吸附时间2.0 h的条件下,吸附在DOEX50WX8 UPW上的K.fragilisβ-D-半乳糖苷酶的酶量与酶活回收率均达到最大值,分别为45.7 mg/g和83.2%。该固定化酶连续使用5次,其活力保留82.6%,固定化酶对乳糖的水解率为87.2%。K.fragilis β-D-galactosidase was immobilized on ionic exchange resin DOEX~ 50WX8 to catalyze the hydrolysis of milk lactose in a batch system. The effects of the pH, initial enzyme concentration and adsorption time were investigated, and the operational stability of the immobilized enzyme and its catalytic efficiency were assayed. The results indicated that the amount of the immobilized enzyme and enzyme recovery reached maximum value at pH value of 7.0, initial enzyme concentration 10.0 mg/mL and 2.0 h. The immobilized enzyme retained 82.6% activity and the degree of lactose hydrolysis was 87.2% after 5 times use.

关 键 词：K fragilis Β-D-半乳糖苷酶 固定化 离子吸附 乳糖水解 

分 类 号：TS201.25[轻工技术与工程—食品科学]