Study on Alkaline Protease Production by Immobilized Serratia marcescens in Carrageenan
卡拉胶固定粘质赛氏菌产碱性蛋白酶的研究

The strain Serratia marcescens S3 was immobilized in carrageenan to produce alkaline protease and the optimum concentration of carrageenan was 2. 5%. Under the optimum culture conditions, the protease activity reached about 400u/ml. By adding 1% soybean meal and 3% corn meal or 2% sands to carrageenan, 25% and 23. 9% higher protease activities could be realized. The half life of producing proteasee by immobilized cells was 14 times (24h percycle) in culture flask simicoritinuous fermentation, and 52 times (12h per cycle) in liquid cycling apparatus fermentation, The efficiencies of producing protease in these two processes were 11. 8% and 45. 07% higher than that by free cells in'culture flask batch fermentation. Moreover, the efficiency of producing protease in liquid cyclying appartus fermentation was 29. 7% higher than that in culture flask simicontinuous fermentation.