一株纤维素酶产生菌的筛选鉴定

Screening and Identifying of a Cellulase-Producing Strain

用CMC平板筛选方法,从草丛土样中筛选到一株产纤维素酶的菌株,该菌在20℃～50℃、pH4.0～10.0、NaCl1.0%～10.0%的条件下均能生长,在26℃～39℃、pH6.0～8.0、NaCl4.0%～6.0%条件下生长快速。经采用Biolog进行碳源利用鉴定判定为黄曲霉,命名为AF-1。AF-1的CMCase为19.26U/mL,FPA为6.22U/mL,纤维分解率为20.6%。采用单因素法对AF-1产酶条件进行了初步测定。

A cellulase-producing strain was isolated from a herby soil in Sichuan Zigong by culture medium which have sodium carboxymethyl cellulose. The strain was identified as Aspergillus flavus by Biolog and named AF-1. Strain AF-1 could grow and excreted cellulase at a wide range of pH, from 4.0 to 10.0, and temperature from 20 ℃ to 50 ℃, and NaCl from 1.0% to 10.0%. The cellulase activity （CMCase） of AF-1 was 19.26 U/mL, the cellulase activity （FPA） was 6.22 U/mL, and the resolution ratio of cellulosic fibre was 20.6%. Optimal enzymatic secretion conditions of AF-1 were 26 ℃-39 ℃, pH 6.8%-8.0%, NaCl 4.0%-6.0%.