• 文献标题:   Co-immobilization of cellulase and glucose oxidase on graphene oxide by covalent bonds: a biocatalytic system for one-pot conversion of gluconic acid from carboxymethyl cellulose
  • 文献类型:   Article
  • 作  者:   ZHANG H, HUA SF, ZHANG L
  • 作者关键词:   cellulase, glucose oxidase, coimmobilization, graphene oxide
  • 出版物名称:   JOURNAL OF CHEMICAL TECHNOLOGY BIOTECHNOLOGY
  • ISSN:   0268-2575 EI 1097-4660
  • 通讯作者地址:   Henan Polytech Univ
  • 被引频次:   2
  • DOI:   10.1002/jctb.6296 EA DEC 2019
  • 出版年:   2020

▎ 摘  要

BACKGROUND The objective of this research was to use a step-by-step method to prepare a novel biocatalytic system (GO-CEL-E/N-GA-GOD): -OH and -COOH on the surface of graphene oxide (GO) were used to immobilize cellulase (CEL) and glucose oxidase (GOD), respectively, which may be easier to control the loading of enzymes with different kinds, to achieve the one-pot conversion of gluconic acid from carboxymethyl cellulose (CMC). RESULTS The loadings capability of CEL and GOD on GO-CEL-E/N-GA-GOD were 49.07 +/- 7.47 mg g(-1) and 10.22 +/- 2.03 mg g(-1), respectively. The multi-enzyme systems had shallow temperature and pH optima of 40 degrees C and 5.0. The kinetic constants of GO-CEL-E/N-GA-GOD (of CEL-GOD) were K-m = 0.15 +/- 0.02 (0.43 +/- 0.09) mmol L-1, V-max = 0.18 +/- 0.01 (0.21 +/- 0.07) mu mol L-1 s(-1), and k(cat)/K-m = 24.12 +/- 0.52 (17.74 +/- 0.85) s(-1) mmol(-1) L. Nearly 65% of the initial activity of GO-CEL-E/N-GA-GOD could be retained after seven cycles. Notably the conversion of gluconic acid was able to reach 63.82 +/- 8.03% within 2 h. CONCLUSION Step-by-step immobilization method made full use of different functional groups on GO, avoiding the competition for fixed sites between CEL and GOD in the immobilization processes. The results reflected the feasibility of the strategy to build bio-microsystem as CEL and GOD immobilized on GO by covalent bonds to achieve the conversion from CMC to gluconic acid in one-step. (c) 2019 Society of Chemical Industry