产纤维素酶细菌菌株的分离鉴定及产酶条件优化

Isolation and identification of cellulase-producing bacteria and optimization of their enzyme-producing conditions

该实验分离鉴定了高产纤维素酶细菌菌株并探究其产酶条件。采用3种培养基进行分离筛选。经菌落形态观察、16SrRNA基因序列分析菌株在系统分类地位。通过单因素试验确定最适产酶条件。结果表明,从西岭山原始森林保护区土壤中筛选到1株高产纤维素酶细菌菌株,鉴定为伯克霍尔德氏菌(Burkholderia cepacia)。其最适产酶条件:碳源为麦麸,最佳氮源为酵母粉,接种量为2%(V/V),初始pH值为7,产酶时间为48h。在此条件下,酶活最高可达2.76U/mL。酶学特性研究显示,在pH5.0、温度60℃条件下CMCase酶活力最高。

In order to isolate and identify the high-yield cellulase-producing bacteria and explore their enzyme-producing conditions,the strains were separated and screened by 3 kinds of culture media.The system classification status of strain was analyzed by the colony morphology observation and 16S rRNA gene sequence.The optimum enzyme-producing conditions were determined by single factor experiments.The results showed that the bacteria with high-yield cellulase was screened^om the soil of the original forest reserve in Xiling mountain and identified as Burkholderia cepacia.The optimum enzyme-producing conditions of the strain were wheat bran as carbon source,yeast extract powder as nitrogen source,inoculum 2%(V/V),initial pH 7 and enzyme-producing time 48 h.Under the conditions,the maximum cellulase activity was 2.76 U/ml.The research of enzymatic characteristics showed CMCase activity was the highest under the conditions of pH 5.0 and temperature 60℃,.