Abstract:

On the basis of cis-epoxysuccinate hydrolase (ESH) producing cell ultrasonication, orthogonal experiments were conducted to analyze the effect of substrate concentration, the enzyme concentration and the time of biotransformation on the activity of ESH in the process of L(+)-tartaric acid production with cis-epoxysuecinate as the substrate for fermentation. An extraordinarily faster method for measuring ESH activity was constructed, which was to put 1 g wet cells into 30 mL 0.2 mol/L ES aqueous solution under the condition of 37℃ for 10 min to biotransform and then to measure the concentration of L(+)-tartaric acid with HPLC. This method possesses the advantages of fast speed, high accuracy and small quantities of cells which were suitable for strain selection, inspection of fermentation parameter, optimization of fermentation conditions and industrial production.

Key words: cis-epoxysuccinate hydrolase, ultrasonication, L(+)-tartaric acid, biotransformation

摘要：

在对产顺式环氧琥珀酸水解酶（ESH）的细胞超声破碎的基础上，通过正交实验对细胞中ESH生物转化生产L(+)-酒石酸过程中的底物浓度、酶浓度、转化时间进行了分析，建立了一种快速测定ESH酶活的方法，即1 g湿细胞，30 mL 0.2 mol/L的顺式环氧琥珀酸二钠（ES），置于37℃保温转化10 min后，利用 HPLC测定酒石酸含量。此方法具有快速、准确和细胞用量少的特点，可用于菌种选育、发酵过程检测、发酵条件优化及工业生产。

关键词: 顺式环氧琥珀酸水解酶;超声破碎;L-酒石酸;生物转化