Characterization of xylose reductase from Candida tropicalis immobilized on chitosan bead

• DOI: 10.5897/ajb09.1845
• Publication Date: 2010-08-31
• Authors: Yan‐Qiu Su; Li Wei; Weihua Zhu; Rongqing Yu; Baojing Fei; Tao Wen; Yi Cao; Dairong Qiao
• Keywords: Thermal Stability

A xylose reductase (XR) with high activity and dual coenzyme from Candida tropical was purified to homogeneity by Ni2+-chelating column, immobilized on chitosan bead. Studies free XR systems for determination of optimum temperature, pH, thermal stability, pH operational kinetic parameters were carried out. Free showed higher at 45 50°C, respectively. The 4.5, but had a broader range 4.0-6.0. Thermal stability than that XR. residual was about 40% after 7 cycles batch operation. Km value 30.3 mM, 20.1 which indicated the affinity increased stimulated MnSO4, inhibited NaCl, βME,Glu. In addition, catalytic efficiency NADH as cofactor better enhanced It is first report immobilizing chitosan, relative activity.

Key words: Xylose reductase, crosslinked bead, immobilization, property, NADH, NADPH.