毕赤酵母表面展示棘孢曲霉β-葡萄糖苷酶催化合成APG的工艺条件优化  

Optimization of the Synthesis of Alkyl Glucoside Catalyzed by Aspergillus aculeatus β-glucosidase-displaying Pichia pastoris Whole-cells

作　　者：胡霞艳 刘端玉[1] 郑穗平[1] 

机构地区：[1]华南理工大学生物科学与工程学院,广州510006

出　　处：《生物技术通报》2014年第6期205-210,共6页Biotechnology Bulletin

基　　金：国家自然科学基金项目(31171633);广东省工业科技攻关项目(2010B011000004)

摘　　要：使用毕赤酵母细胞表面展示棘孢曲霉的β-葡萄糖苷酶作为全细胞催化剂,以葡萄糖为底物,在水-醇双相体系中逆水解合成C6-C10烷基糖苷。讨论了含水量、葡萄糖添加量、全细胞催化剂添加量、乙酸-乙酸钠缓冲液pH值和温度等主要因素对反应的影响,并与商品酶苦杏仁β-葡萄糖苷酶、Novozym188进行比较。结果表明,Novozym188不适合逆水解合成APG,苦杏仁β-葡萄糖苷酶反应所需时间短,但最终转化率不如全细胞催化剂。在5 mL反应体系中,合成HG的最优条件:葡萄糖0.1 g,全细胞催化剂0.05 g,10%pH 3.0 buffer;合成OG的最优条件:葡萄糖0.2 g,全细胞催化剂0.05 g,15%pH3.0 buffer;合成DG的最优条件:葡萄糖0.2 g,全细胞催化剂0.2 g,20%pH 3.0 buffer;放置55℃200 r/min恒温振荡器中,反应时间为72 h,HG和DG的最大产率分别为11.69%和3.58%,而OG的产率则在96 h到达最大值6.34%。Aspergillus aculeatus β-glucosidase displayed Pichia pastoris cell surface was used as whole-cell biocatalyst, glucose as substrate, catalyzed synthesis alkyl glucosides of C6-C10 with reverse hydrolysis in water-alcohol two-phase system. The effects of various reaction factors, including water content, whole-cell biocatalyst dose, glucose concentration, pH and temperature were optimized. The catalytic effect of whole-cell biocatalyst were compared with commercial enzyme almond β-glucosidase and Novozym188 . The results showed that Novozym188 was not suitable for synthesis of APG, almondβ-glucosidase need shorter time than whole-cell biocatalyst, but the final conversion of whole-cell biocatalyst was higher. In 5 mL total reaction volume, the optimal reaction conditions of HG：0.1 g glucose, 0.05 g whole-cells biocatalyst, 10%pH3.0 buffer;the optimal reaction conditions of OG：0.2 g glucose, 0.05 g whole-cells biocatalyst, 15%pH3.0 buffer;the optimal reaction conditions of DG：0.2 g glucose, 0.2 g whole-cells biocatalyst, 20%pH3.0 buffer, temperature 55℃, 200 r/min. After 72 h the maximum HG and DG yield could be 11.69%and 3.58%. The highest yield of OG was 6.34%after 96 h.

关 键 词：细胞表面展示 Β-葡萄糖苷酶 全细胞催化剂 烷基糖苷 

分 类 号：Q936[生物学—微生物学]