CIESC Journal ›› 2017, Vol. 68 ›› Issue (4): 1550-1557.DOI: 10.11949/j.issn.0438-1157.20161301

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Immobilized glutamate decarboxylase by carboxyl magnetic microspheres

LI Jianan1,2, XIE Tian3, HU Sheng1, XIE Dongfang3, FANG Hui3, MEI Lehe1,4, HUANG Jun3, WANG Jinbo1, YAO Shanjing4   

  1. 1 School of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, Zhejiang, China;
    2 College of Pharmacy, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China;
    3 School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, Zhejiang, China;
    4 College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, China
  • Received:2016-09-18 Revised:2016-11-09 Online:2017-04-05 Published:2017-04-05
  • Supported by:

    supported by the National Natural Science Foundation of China (31240054, 31470793, 31670804), the Natural Science Foundation of Zhejiang Province (LZ13B060002) and the Natural Science Foundation of Ningbo (2013A610087).

羧基化磁性微球固定化谷氨酸脱羧酶

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   

  1. 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
  • 通讯作者: 梅乐和,黄俊
  • 基金资助:

    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)。

Abstract:

Carboxyl Fe3O4 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 compared. The results showed that immobilized GAD had better thermostability and pH resistance and retained more than 90% activity after ten repeated batches.

Key words: carboxyl magnetic microspheres, glutamate decarboxylase, immobilization, stability, preparation

摘要:

通过化学共沉淀法结合高锰酸钾氧化制备羧基化Fe3O4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%。

关键词: 羧基化磁性微球, 谷氨酸脱羧酶, 固定化, 稳定性, 制备

CLC Number: