羟基乙腈水解酶菌株的筛选及其催化特性

Isolation and catalytic characteristics of a glycolonitrile-hydrolyzing strain

摘要:

以羟基乙腈为唯一氮源, 从土壤中筛选到一株腈水解酶产生菌CCZU-12, 经形态观察、生理生化实验和16S rDNA序列分析, 鉴定该菌为假单胞菌属(Pseudomonas sp.)。对菌株CCZU-12产腈水解酶的培养条件及催化反应条件进行优化, 最适产酶培养条件为: 碳源为10 g/L乙酸钠, 氮源为5 g/L酵母粉, 金属离子为1.0 mmol/L Mg2+, 培养温度30 °C, pH值7.0, 接种量4%, 装液量50 mL/250 mL; 最适催化反应温度35 °C, pH值7.0, 反应120 h, 羟基乙腈转化率达到98.9%。

Abstract:

A strain CCZU-12 with high glycolonitrile-hydrolyzing activity has been isolated using glycolonitrile as sole nitrogen source. It was identified as Pseudomonas sp. by its morphological, physiological properties and 16S rDNA sequence analysis. The preferred carbon/nitrogen sources and metal ions were sodium acetate (10 g/L), yeast extract (5 g/L), and Mg2+ (1.0 mmol/L), respectively. The optimum culture conditions were the filling volume 50 mL in 250 mL shaking flask, inoculum 4%, temperature 30 °C, and initial pH 7.0. After hydrolysis of glycolonitrile for 120 h, glycolic acid was obtained in a yield of 98.9% at the optimum reaction temperature 35 °C and pH 7.0.