文献类型： 外文期刊

作者： Wu, Yuqiu ¹ ; Meng, Fanjin ¹ ; Fu, Jiaolong ¹ ; Zhou, Yuyang ¹ ; Fan, Huan ² ; Ju, Xin ¹ ; Li, Liangzhi ¹ ;

作者机构： 1.Suzhou Univ Sci & Technol, Sch Chem & Life Sci, 99 Xuefu Rd, Suzhou 215009, Jiangsu, Peoples R China

2.Tianjin Acad Agr Sci, Inst Anim Sci & Vet, Tianjin 300381, Peoples R China

关键词： Co-immobilization; D-ribulose isomerase; D-tagatose-3-epimerase

期刊名称：MOLECULAR CATALYSIS （ 影响因子：4.6； 五年影响因子：4.2 ）

ISSN： 2468-8231

年卷期： 2024 年 555 卷

页码：

收录情况： SCI

摘要： D-xylose, a biomass derivative, is used as a substrate to generate D-xylulose and D-ribulose with high-added value through a cascade reaction. During this process, the thermal stability and catalytic efficiency of rate-limiting enzymes during cascade reactions are important issues that must be addressed in industrial applications. In this study, we prepared and validated PDA/SiO2 microspheres as highly loaded immobilization carriers by oxidative self-polymerization of polydopamine (PDA) on silica (SiO2) microspheres. D-xylose was successfully catalyzed by the co-immobilized D-5-phosphate ribose isomerase B (RpiB) and D-tagatose-3-epimerase (DTE), denoted PDA/SiO2-RpiB-DTE, to produce D-ribulose and D-xylulose. After immobilization, the K-m of co-immobilized RpiB and DTE decreased, which suggested increased substrate affinity. The half-life of the co-immobilized enzymes was 3.5-8 fold higher than that of the free enzymes at 50-70 degrees C, and the inactivation rate constant was reduced, demonstrating that immobilization improved significantly the thermal stability. The conversion of D-xylose at 10 mM was 29.98% under optimal conditions, which contained 9.85% D-ribulose and 20.13% D-xylulose. PDA/SiO2-RpiB-DTE showed up to 89.10% initial enzyme activity after 3 recycle runs. The thermal stability and recovery aspects were improved by immobilization, which facilitates the use of biomass to produce high-value-added products and further exploitation.