产纤维素酶细菌的筛选鉴定与特性分析

Screening, Identification and Characteristic Analysis of Cellulase-Producing Bacteria

为了筛选获得产纤维素酶细菌,为新型饲料添加剂的开发提供材料基础。本研究以玉米田土壤为样品,使用刚果红平板法筛选产纤维素酶细菌并分析其所产酶的特性。通过试验,筛选获得产纤维素酶菌株,经形态学和分子生物学法将其鉴定为巨大芽孢杆菌(Bacillus megaterium)。对巨大芽孢杆菌XT2所产纤维素酶进行酶学特性分析,发现其最适反应条件为50℃,pH 6.0,具有一定的热稳定性,K+对纤维素酶具有激活作用,Mg^(2+)、Ca^(2+)和Mn^(2+)对酶活具有抑制作用。该菌生长至20 h时,所产纤维素酶活力最高,达到0.774 U/mL。该产纤维素酶芽孢杆菌的成功分离获取为饲料新资源的开发以及新型饲料添加剂的研制提供了菌种材料。

To screen cellulase-producing bacteria and provide a material basis for the development of new feed additives, in this study, soil samples from corn fields were used to screen cellulase-producing bacteria by congo red plate method, and the characteristics of cellulase produced by it were analyzed. Through the test,the cellulase-producing strain was screened and identified as Bacillus megaterium by morphological and molecular biological methods. The enzymatic characteristics of cellulase produced by Bacillus megaterium XT2 was analyzed and the optimal reaction condition was found to be 50℃ and pH 6.0, and the cellulase showed certain thermal stability, K+could activate the cellulase activity, and Mg^(2+), Ca^(2+) and Mn^(2+) had an inhibitory effect on enzyme activity. When the strain grew to 20 h, the cellulase activity reached the highest(0.774 U/mL).The successful isolation of cellulase-producing Bacillus could provide a strain material for the development of new feed resources and new feed additives.