Breeding of high-yield Douchi fibrinolytic enzyme strain by ultraviolet mutagenesis and optimization of enzyme-producing conditions
Using Douchi fibrinolytic enzyme-producing strain Bacillus subtilis DC-1 isolated from Douchi samples as the original strain,the high-yield Douchi fibrinolytic enzyme strain with stable inheritance was bred by ultraviolet mutagenesis,and the fermentation conditions were optimized by sin-gle factor tests and orthogonal tests using Douchi fibrinolytic enzyme activity as evaluation index.The results showed that a mutagenic strain DC-V5 with high Douchi fibrinolytic enzyme activity and genetic stability was obtained,and the optimal fermentation conditions were as follows:inoculum 3％,liquid loading volume 70 ml/250 ml,fermentation temperature 34 ℃ and initial pH 6.5.Under the optimal fermentation conditions,the Douchi fibrinolytic enzyme activity of strain DC-V5 reached(451.26±11.09)IU/ml,which was 1.74 times that of the original strain DC-1.
万方数据
维普
