磁性聚合物微球固定化发酵液中脂肪酶  

Immobilization of lipase in fermentation broth by magnetic polymer microspheres

作　　者：郭俊宏 王添誉 孙西同 李佥[1] 陈晓艺[1] 李苗 曾祥冰 黄帆 李宪臻[1] GUO Junhong;WANG Tianyu;SUN Xitong;LI Qian;CHEN Xiaoyi;LI Miao;ZENG Xiangbing;HUANG Fan;LI Xianzhen(School of Biological Engineering,Dalian Polytechnic University,Dalian 116034,China;School of Light Industry&Chemical Engineering,Dalian Polytechnic University,Dalian 116034,China)

机构地区：[1]大连工业大学生物工程学院,辽宁大连116034 [2]大连工业大学轻工与化学工程学院,辽宁大连116034

出　　处：《食品与发酵工业》2023年第23期141-148,共8页Food and Fermentation Industries

基　　金：国家自然科学基金青年基金项目(31601411,21804129,22108024);辽宁省教育厅科学研究项目(JYTMS20230423)。

摘　　要：脂肪酶是一类功能多样且应用广泛的酶,但是由于游离酶活性易损失且难以分离回收,通常不适合实际应用。为了解决实际应用中游离脂肪酶的稳定性和重复使用性较差的问题,首先使用近平滑假丝酵母发酵生产脂肪酶,然后合成了聚酰胺-胺树枝状大分子接枝的聚甲基丙烯酸甲酯磁性微球[Fe_(3)O_(4)@poly(methyl methacrylate)/polyamidoamine,Fe_(3)O_(4)@PMMA/PAMAM],并用多种方法对其进行表征。进一步将Fe_(3)O_(4)@PMMA/PAMAM作为载体用于固定化脂肪酶,最优固定化条件为戊二醛用量0.6 mL、固定化时间5 h、固定化pH 8.0、固定化温度35℃,所得的固定化脂肪酶活性为864 U/g,酶活力回收率为74.29%。与发酵液中的游离脂肪酶相比,固定化脂肪酶的热稳定性和pH稳定性均明显增强。在连续循环使用10次后,固定化脂肪酶仍能维持72.23%的酶活性。4℃下贮存30 d后,固定化脂肪酶仍能保留71.44%的酶活性。Lipase is an enzyme with diverse functions and broad applications.However,due to the easy loss of enzyme activity and difficulty of being separated and recovered,free lipase is usually not suitable for practical application.In order to improve the poor stability and reusability of free lipase in application,in this study,Candida parapsilosis was first used to produce lipase.Then,polyamidoamine dendrimers grafted magnetic poly(methyl methacrylate)microspheres[Fe_(3)O_(4)@poly(methyl methacrylate)/polyamidoamine,Fe_(3)O_(4)@PMMA/PAMAM]were synthesized and characterized in various ways.Subsequently,Fe_(3)O_(4)@PMMA/PAMAM was used as the support for lipase immobilization.The optimal immobilization conditions were determined as follows:0.6 mL glutaraldehyde,5 h,pH 8.0,and 35℃.Under these conditions,the immobilized lipase exhibited an activity of 864 U/g and the activity recovery of immobilized lipase was 74.29%.Compared with the free lipase in fermentation broth,the thermal stability and pH stability of immobilized lipase were enhanced significantly.After repeated use for 10 times,immobilized lipase still maintained 72.23%of its initial activity.After 30 d of storage at 4℃,the immobilized lipase still retained 71.44%of its initial activity.It was indicated that Fe_(3)O_(4)@PMMA/PAMAM immobilized lipase had good enzyme activity,stability and reusability.

关 键 词：磁性材料 树枝状接枝 固定化脂肪酶 酶学性质 近平滑假丝酵母 

分 类 号：TQ925.6[轻工技术与工程—发酵工程]