白蚁肠道纤维素分解菌的筛选鉴定及产酶条件的研究

Screening and Identification of A Strain of Cellulose-degrading Actinomyces from Termite Intestine and Its Optimal Conditions for Enzymatic Production

从白蚁肠道中筛选出1株强降解纤维素的菌，经培养特征及生理生化试验初步鉴定其隶属于放线菌类链霉菌属菌株。液体摇瓶发酵试验显示其最佳的摇瓶发酵培养基配方为：CMC5g、（NH4）2SO46g牛肉膏6g、KH2PO40．50g,MgSO4·7H2O0．50g、CaCl20．10g、FeSO40．10g、水1000mL；产酶最佳条件：发酵时间约120h、起始pH为5．0、装料量为60～80mL。此时分解菌所产酶酶活最高，其CMC酶活、滤纸酶活、脱脂棉酶活分别达到583、1654和28单位。

A strain with strong capability of degradaing cellulose was screened from termite intestines, and identified preliminarily as a Streptomyces. sp. （actinomyces） by its cultured charateristics, physiological and biochemical test. The results from the liquid fermentation in shaking flask showed that the best fermentation medium was composed of CMC 5 g, （ NH4 ） 2 SO4 6 g, beef extract 6 g, KH2 PO4 0.50 g, MgSO4 · 7H2O 0.50 g, CaCl2 0.10 g, FeSO4 0. 10 g, H2O 1 000 mL. The optimal conditions were fermentation time 120 h, initial pH 5.0, filled substrate 60-80 mL,under which the enzymatic activities were the highest with CMCase 583 U, Fpase 1 654 U and C1 28 U respectively.