Effects of Environmental and Nutritional Conditions on Fibrinolytic enzyme Production from Bacillus subtilis BK-17 in Flask Culture

플라스크 배양에서 Bacillus subtilis BK-17의 혈전용해효소 생산에 대한 환경 및 영양 조건의 영향

The production of fibrinolytic enzyme from Bacillus subtilis BK-17 was studied in the shake flask cultures. The important medium components studied include nitrogen source, carbon source and inorganic salts. The environmental conditions include initial pH, temperature, shaking speed and working volume. Among various N-sources, C-sources and inorganic salts tested, soybean flour, D-glucose and Na2HPO4 gave the best results, and their optimal concentrations were 1.5%, 0.5% and 0.05%, respectively. The optimal pH and temperature were 9.0 and 37$^{\circ}C$. With decreasing working volume in the range of 25∼100ml in the 250ml flask or increasing shaking speed in the range of 100∼300rpm, the enzyme production was greatly enhanced. The enzyme activity under the optimal conditions was about 1400I.U./ml with urokinase as a standard.