Preparation of immobilized halohydrin dehalogenase and the stability testing of catalytic systhesis ATS-5
LIANG Guobin
ZHAI Liangchuang
WANG Bin
YAO Jia
ZHOU Quanfa
Abstract：The immobilization conditions of halohydrin dehalogenase (HHDH) by the sodium alginate were studied.The optimum conditions of immobilization process were as follows: sodium alginate concentration 3.5% , HHDH enzymatic amount 2.4×10 4 U/mL, glutaraldehyde concentration 1.00%, calcium chloride solution concentration 1.5% and immobilization time 2 h.Under the optimum immobilization conditions, the encapsulation efficiency of HHDH was 52.1%, the activity recovery of HHDH was 75.2%.After five batches of intermittent catalytic synthesis of (R)-4-cyano- 3-hydroxybutyric acid ethyl (ATS-5), the residual activity of immobilized HHDH was 51.2%. After the continuous catalytic synthesis of ATS-5 for 10 d,the substrate conversion efficiency was 90.6%, the distillation purification yield of ATS-5 was 98.2%, the purity and optical purity of ATS-5 were 99.3% and 99.1%, respectively .No obvious activity loss was obtained for immobilized HHDH after 80 d storage at 4 ℃.
Keywords：(R)-4-cyano-3- hydroxybutyric acid ethylimmobilizationhalohydrin dehaloge- nasecatalytic stability
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 26-32 )