固定化酵母细胞生物合成胞苷三磷酸工艺的优化  

Optimization of CTP Biosynthesis by Immobilized Yeast Cells

作　　者：李红梅[1] 马伟[1] 王伟洁[1] 

机构地区：[1]上海理工大学医疗器械与食品学院,上海200093

出　　处：《食品科学》2012年第19期259-263,共5页Food Science

摘　　要：以胞苷一磷酸(CMP)为底物,采用响应面分析法对固定化酵母细胞发酵制备胞苷三磷酸(CTP)的影响因素进行优化,采用HPLC法对CTP定量。结果表明:在CTP生物合成中磷酸根离子和Mg2+浓度存在一个临界浓度低于临界浓度二者将限制CTP产率;在本实验范围内固定化酵母发酵制备CTP的最佳工艺为:20mL底物样液添加20g固定化酵母,CMP浓度100mmol/L、葡萄糖浓度100mmol/L、磷酸盐浓度250mmol/L、Mg2+浓度15mmol/L、pH6.1、反应时间2h,在此条件下CTP的产率可达67.89%。Response surface methodology was employed to optimize the biosynthesis of cytidine triphosphate （CTP） from cytidine monophosphate （CMP） by immobilized yeast cells. CTP was analyzed by HPLC. Critical phosphate ion and Mg^2＋ concentrations for CTP synthesis were found and CTP yield was restricted when phosphate ion and Mg^2＋ were lower than their respective critical concentrations. The optimal CTP synthesis conditions were determined as follows： 20 g of immobilized yeast cells were cultured in 20 mL of 100 mmol/L CMP containing 100 mmol/L glucose, 250 mmol/L phosphate and 15 mrnol/L Mg^2＋ at pH 6.1 for 2 h. Under these conditions, the yield of CTP was up to 67.89%.

关 键 词：胞苷三磷酸 固定化酵母 生物转化 响应面分析法 

分 类 号：TS261.1[轻工技术与工程—发酵工程]