半纤维素降解菌J-16的筛选及产酶特性研究

Screening,Identification and Enzymatic Analysis of Hemicellulose Degrading Bacteria J-16

从腐烂竹子表面采集样品经初筛、复筛获得1株半纤维素高效降解菌。采用半纤维素平板水解圈法和胞外酶测定法进行菌株筛选,利用培养特征形态学生理生化特征和分子生物学方法进行菌株鉴定,并对产酶特性和酶学性质进行了研究。结果表明,该菌株初步鉴定为类芽胞杆菌属细菌,命名为Paenibacillus sp.J-16,最适碳源和氮源分别为麸皮(20 g/L)和豆粕(15 g/L),在初始pH值为6.5,装液量为50 mL,32℃条件下180 r/min培养60 h,酶活性达到192.6 U/mL。该菌株的获得为采用生物法降解半纤维素的研究与应用提供了实践依据。

A hemicellulose degrading bacteria was isolated from the surface of the rotting bamboo. The methods used to screen the effective strains included hydrolysis spot diameter measurement of hemieellulose plate and extracellular enzyme activity. Culture characteristics, morphological, physiological-biochemical characteristics and molecular biological methods were used to identify the strain, and characteristics of enzyme production and enzymatic properties were studied. Results indicated that the strain obtained with efficient hemicellulose degrading ability, was identified as Paenibacillus sp. J-16. With optimization of fermentation conditions as optimum carbon source of bran 20 g/L, nitrogen source of soybean meal 15 g/L, enzymatic temperature 32℃, initial pH 6.5 and liquid volume 50 mL, the enzyme activity reached 192.6 U/mL after it was cultured for 60 hours in incubator. The study will provide a practical basis for research and application of biological degradation of the hemicellulose.