卡拉胶固定粘质赛氏菌产碱性蛋白酶的研究

将粘质赛氏菌(Seratia marcescens)包埋于卡拉胶中，发现2．5％的卡拉胶适于固定该菌产碱性蛋白酶。固定化细胞在其较适宜产酶培养基中发酵，酶活力一般可达400u/ml，在卡拉胶中添加3％玉米粉和1%豆饼粉或2％砂子制备固定化细胞，其产酶能力分别提高了25%和23．9％；固定化细胞颗粒越小，其产酶能力越高。采用摇瓶半连续发酵。其产酶半衰期为14次(24小时为一个周期)；而用环流器进行半连续发酵，其产酶半衰期为52次(12小时为一个周期)，产酶效率分别比游离细胞摇瓶发酵的产酶效率高11．8％和45．07％，而环流器半连续发酵的产酶效率比摇瓶半连续发酵高29．7％。

Study on Alkaline Protease Production by Immobilized Serratia marcescens in Carrageenan

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.