碱性过氧化氢酶高产菌的筛选、鉴定及发酵条件优化

Screening, Identification and Fermentation Optimization of a Alkaline Catalase-Producing Strain

从纺织厂的车间污水分离获得菌株WSHDZ-01,其产过氧化氢酶酶活为600U/mL,酶活的pH范围为5.0-12.0。根据对该过氧化氢酶生产菌的形态和生理生化特征的分析和16SrDNA序列分析,鉴定该菌为枯草芽孢杆菌。通过对该菌株发酵培养基中碳氮源的优化,其最佳碳源为10g/L的葡萄糖,氮源为5g/L的NaNO3,在此条件下产酶达3258U/mL。此外,该菌株所产过氧化氢酶的最适反应pH为11.0,最适温度为55℃,在pH11.0和50℃下保持15min后,剩余酶活仍达98%以上。

A strain named as WSHDZ-01 with high capability of producing alkaline catalase（CAT） was isolated from the wastewater discharged from a textile factory. The catalase from this strain was active in the range of pH 5.0-pHI2,0, and the highest enzyme activity was observed as 600 U/mL at pH 7.0. According to the physiological and biochemical characteristics and 16S rDNA sequence of WSHDZ-01, the strain was identified as Bacillus subtilis. The optimal carbon source and nitrogen source were also determined as 10 g/L glucose and 5 g/L NaNO3, respectively. The highest enzyme activity of 3258 U/mL was achieved after the optimization. The resultant catalase reacted best at 55 ℃ and pH 11.0, and had activities 〉 98% after 15 min maintenance under 50℃ and pH 11.0.