期刊
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
卷 105, 期 -, 页码 894-904出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.ijbiomac.2017.07.102
关键词
Porous chitosan; Mechanical properties; Sodium carbonate; Glutaraldehyde; Covalent immobilization
资金
- National Research Center, Egypt
Porous chitosan beads of superior mechanical properties were produced via a two stepped treatment process. First, the chitosan ionotropic gelation solution was supplemented with Na2CO3, which acted as a porogen. Afterwards, the beads were chemically cross-linked with glutaraldehyde. This treatment also caused the produced porous chitosan beads to acquire higher observed activities of immobilized beta-D-galactosidase (beta-gal). The observed activities of the beta-gal immobilized onto the 0.2 M and the 0.35 M Na2CO3 treated beads were 1.63 and 1.91 fold respectively, higher than the activity offered by the control beads. Nevertheless, both the control beads and the 0.2 M Na2CO3 beads caused the optimum pH range of beta-gal to shift from 4.6-5.1 to similar to 2.7-5. The enzyme's optimum temperature shifted from 55 to 60 degrees C after its immobilization onto the control chitosan beads whereas the beta-gal immobilized onto the 0.2 M Na2CO3 chitosan beads exhibited a temperature optimum of 55-60 degrees C. The reusability study revealed the superiority of the 0.2 M Na2CO3 treated beads which retained 59.1% of their initial activity during the 13th enzymatic cycle. On the other hand, the control chitosan beads were fragmented and lost their activity after only four enzymatic cycles. (C) 2017 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据