普鲁兰酶产生菌的筛选鉴定与发酵条件的研究

Screening,Identification of Pullulanase-Producing Strain and Optimization of its Fermentation Conditions

从海洋中分离出了一株产普鲁兰酶活性较高的菌株BCT-1,初步鉴定为不动杆菌(Acinetobacter sp.)。通过对发酵培养基以及发酵条件的优化,使普鲁兰酶的酶活力达到2.347 U/mL。优化后的发酵培养基成分如下:0.02 g/mL玉米淀粉,0.01 g/mL^0.012 5 g/mL酵母膏,0.001 g/mL KH2PO4,0.000 5 g/mL MgSO.47H2O及0.000 01 g/mL FeSO4.7H2O。最佳培养条件为:发酵初始pH 6.0,接种量为8%,培养温度30℃,500 mL摇瓶装液量为150 mL,摇瓶转速为200 r/min,发酵周期72 h。

A stain BCT-1 having pullulanase activity was isolated from Hainan marine.The isolated was identified as a strain of Acinetobacter sp.Maximal enzyme activity was achieved 72 h of shaking cultivation at 30 ℃ and at initial pH of 6.0,on a medium composed of 0.02 g/mL corn starch,0.01 g/mL-0.012 5 g/mL yeast extract,0.001g/mL KH2PO4,0.000 5 g/mL MgSO4·7H2O and 0.000 01g/mL FeSO4·7H2O.The optimum culture condition were as follows： amount of inoculation 18 mL/100 mL,500 mL flask containing medium 150 mL,shaking at 200 r/min.