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

Abstract:

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-pH12.0, 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.