一株木薯纤维素分解菌的发酵条件和产酶特性研究

Study on the fermentation process and the characteristics of enzyme from cellulase-producing bacteria for the cassava

从土壤中筛选出的一株纤维素分解菌为实验菌,以木薯粉为原料发酵,研究此菌的最佳产酶条件及其酶的性质。通过正交实验得到最佳产酶条件为初始pH为4.0,木薯粉添加量为25g/L培养液,接种量为1.5%(V/V),在33℃下恒温振荡发酵56h,此时CMC酶活高达16.982U/mL。菌体在肉汤培养基上培养24h菌体浓度最大。此菌所产酶的最适反应温度为50℃,最适反应pH为5.0,最适反应时间为60min。

The fermentation process and characteristics of the enzyme was studied on a cellulase-producing bacteria isolated from soil. The cellulase-producing process were optimized by orthogonal experiments,the optimal fermentation process was pH4.0,concentration of cassava in the culture solution 25g/L,bacteria inoculation 1.5% （V/V）,shake culture for 56h in 33℃ ,the CMCase activity under these conditions achieved 16.982U/mL. The celt concentration attained the highest when the cellulase-producing bacteria was cultured for 24h in broth medium. The characteristics of the enzyme was confirmed,the optimal reaction temperature was 50℃,the optimal pH was 5.0,the optimal time was 60min.