环氧基载体固定化K．fragilisβ-D-半乳糖苷酶催化合成低聚半乳糖  

Catalytic synthesis of galactooligosaccharides by K.fragilis β-D-galactosidase immobilized on epoxy carrier

作　　者：路艳丽[1] 秦艳[1] 刘建福[1] 

机构地区：[1]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：《食品工业科技》2013年第9期168-171,共4页Science and Technology of Food Industry

基　　金：国家高技术研究发展计划(863计划)(2008AA10Z301)

摘　　要：采用悬浮聚合法制备了表面含有活性环氧基的载体,研究了初始酶浓度及反应时间对该载体固定化K.fragilis-β-D-半乳糖苷酶效率的影响,应用环氧基载体固定化酶催化合成低聚半乳糖,探讨影响低聚半乳糖合成量的因素。结果表明:制备的环氧基载体为单一分散、近似球形、粒径约为150～200μm的球体。初始酶浓度为4.0mg/mL,环氧基载体对K.fragilis-β-D-半乳糖苷酶的固定化量达到最大值,为69.8mg/g载体,初始酶浓度为3.0mg/mL时,固定化酶的活力回收率最大,约为70%。固定化的酶量随着固定化的时间增加而增加,固定化10h时酶量达到最大值。固定化K.fragilis-β-D-半乳糖苷酶催化合成低聚半乳糖的最适底物浓度为150g/L,反应4hGOS的产率达到最大,为40g/L。The carrier with active epoxy group was prepared by suspension polymerization. Effect of initial enzyme concentration and reaction time on the K.fragilisβ-D-galactosidase immobilization efficeiency was evaluated ,and the factors which influenced the synthetic amout of galactooligosaccharides by immobilizedK.fragilisβ-D- galactosidase were researched.The results showed that the prepared epoxy group carrier was single scattered and approximate spherical spheres with particle size about 150-200μm.When initial enzyme concentration was 3.0mg/mL,the quantity of immobilized K.fragilis 13-D-galactosidase,which has the higher recovery of immobilized enzyme activity 70%, achieved the maximum （69.8mg/g）. With immobilized time increased, The amount of immobilized enzyme increased and reached the maximum at 10h . Under the optimum condition （substrate concentration：150g/L, reaction time： 4h）, the yield of GOS synthetized by immobilized K.fragilis-f5- D- galactosidase enzyme was the best.

关 键 词：环氧基载体 半乳糖甘酶 固定化 低聚半乳糖 

分 类 号：TS201.3[轻工技术与工程—食品科学]