Study on fermentation technology of marine Bacillus subtils for producing the fibrinolytic enzyme

The marine Bacillus subtils LJ-22 which produces fibrinolytic enzyme was optimized its solid and liquid fermentation conditions, determine the optimal liquid fermentation conditions were as follows:temperature 31℃, initial pH7.0, inoculum 4%, the rotation speed 180r/min for 72h. The optimal solid fermentation conditions were as follows :temperature 34℃ , initial pH7.0 , inoculums 10% , sample loading volume 10g , fermentation cultivate for 72h.Under those conditions, the liquid fermentation produce the activity of fibrinolytic enzyme reached (830±12.5) IU/mL, which was 1.69 folds as high as that of the initial strain , the solid fermentation produce the activity of fibrinolytic enzyme reached (4300±12.8) IU/g, which was 1.56 folds as high as that of the initial strain. Through comparing the solid fermentation conditions and the activity of fibrinolytic enzyme with the liquid fermentation’s, it was found that the marine Bacillus subtils LJ -22 was more suite for liquid fermentation, meanwhile was facilitate large-scale industrial production.