羧基化磁性微球固定化谷氨酸脱羧酶  

Immobilized glutamate decarboxylase by carboxyl magnetic microspheres

作　　者：李佳男[1,2] 谢湉[3] 胡升[1] 谢东芳[3] 方卉[3] 梅乐和[1,4] 黄俊[3] 王进波[1] 姚善泾[4] LI Jianan XIE Tian HU Sheng XIE Dongfang FANG Hui MEI Lehe HUANG Jun WANG Jinbo YAO Shanjing(School of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, Zhejiang, China College of Pharmacy, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, Zhejiang, China College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, China)

机构地区：[1]浙江大学宁波理工学院生物与化学工程学院,浙江宁波315100 [2]浙江工业大学药学院,浙江杭州310014 [3]浙江科技学院省农产品化学与生物加工技术重点实验室,浙江杭州310023 [4]浙江大学化学工程与生物工程学院,浙江杭州310027

出　　处：《化工学报》2017年第4期1550-1557,共8页CIESC Journal

基　　金：国家自然科学基金项目(31240054;31470793;31670804);浙江省自然科学基金重点项目(LZ13B060002);宁波市自然科学基金项目(2013A610087)~~

摘　　要：通过化学共沉淀法结合高锰酸钾氧化制备羧基化Fe_3O_4磁性微球,以该磁性微球作为载体,固定化谷氨酸脱羧酶。利用热重分析(TGA)、透射电镜(TEM)及振动样品磁强计(VSM)对羧基化磁性微球进行表征,结果表明该磁性微球磁含量约为95.1%,粒径均一,呈近似球形且具有超顺磁性。通过对固定化酶进行傅里叶红外光谱(FT-IR)、VSM和X射线衍射(XRD)分析,确定磁性微球载体与谷氨酸脱羧酶分子间形成酰胺键,实现共价结合且固定化酶前后粒子晶形完整,均具有良好的磁响应能力和超顺磁性。与游离谷氨酸脱羧酶相比,固定化酶的热稳定性和酸碱耐受性均有不同程度的提高,且制备的固定化酶重复使用10批后相对酶活力仍大于90%。Carboxyl Fe304 magnetic microspheres were prepared by a chemical co-precipitation method with potassium permanganate oxidation, and glutamate decarboxylase （GAD） was immobilized by the carboxyl magnetic microspheres as a carrier. The magnetic microspheres were characterized by methods of thermogravimetry （TGA）, transmission electron microscopy （TEM） and vibrating sample magnetometer （VSM）. The results indicated that the magnetic microspheres had 95.1% contents of magnetite, homogeneous size and superparamagnetic behavior. GAD was well wrapped up in the magnetic microspheres by Fourier transform infrared （FT-IR） analysis, VSM and X-ray diffraction （XRD）. The magnetic microspheres had complete crystal structure, good magnetic response and strong superparamagnetic behaviors before and after GAD immobilization. The enzymatic properties of immobilized and free GAD were analyzed and comoared. The results showed that immobilized GAD had better thermostability and pH resistance and retained more than 90% activity after ten repeated batches.

关 键 词：羧基化磁性微球 谷氨酸脱羧酶 固定化 稳定性 制备 

分 类 号：TQ028.8[化学工程]