一组小麦秸秆好氧分解菌系的构建及组成多样性  

Characteristics and Diversity of a Microbial Community Decomposing Wheat Straw Under Aerobic Conditions

作　　者：董玉玲[1,2] 朱万斌[1,3] 郭鹏[1] 王小芬[1,3] 张利莉[2] 崔宗均[1,3] 

机构地区：[1]中国农业大学农学与生物技术学院,北京100193 [2]塔里木大学新疆生产建设兵团塔里木盆地生物资源保护利用重点实验室,阿拉尔843300 [3]中国农业大学生物质工程中心,北京100193

出　　处：《环境科学》2010年第1期249-254,共6页Environmental Science

基　　金："十一五"国家科技支撑计划重大项目(2006BAD07A01);教育部高校博士点新教师基金项目(20070019055);国家自然科学基金青年基金项目(30800672)

摘　　要：采用"外淘汰法"在常温、好氧条件下构建了一组稳定、有效降解小麦秸秆的复合系.复合系分解能力的研究表明,在100mL改良CMC培养基(液面深度2 cm和直径9 cm)中,分解的前6 d复合系保持较高分解能力,减重率达到66.1%,6 d后复合系分解能力逐渐减弱,到第10 d时减重率达到77.0%.1.86 g秸秆各成分中,纤维素分解0.78 g,半纤维素分解0.16 g,木质素分解0.24 g.复合系组成多样性的研究表明,通过克隆文库构建和单菌株分离共确定出13个菌属的微生物,优势菌属有Hydrogenophaga、Pseudomonas、Bacteroides和Clostridium,占100个阳性克隆子的78%.系统发育关系表明,克隆文库和单菌分离技术分别所确定的微生物种类及亲缘关系存在一定的差异;Isolated 7(FJ439527)和Clone 86(EU834839)与假单胞菌属中的厦门藻(Pseudomonas xiamenensis)亲缘关系较近.A microbial community with the stable ability of effectively decomposing wheat stalks was constructed at room temperature under aerobic conditions by the method of restricted cultivation.The degradation ability of the microbial community shows that when performed in 100 mL improved CMC liquid medium,the depth and diamerer of the fluid level were 2 cm and 9 cm,it kept higher degradation efficiency with capability of decomposing straws of 66.1% during the initial six days.By the tenth day of decomposition,the degradation ratio was slowly up to 77.0%.Analysis of the components of wheat stalk（1.86 g） showed that the cellulose lost 0.78 g,hemicellulose lost 0.16 g and lignin lost 0.24 g.The composition diversity of the microbial community shows that 13 genera of microorganisms were identified by the technologies of clone library and isolation of pure strain.The results indicated that the dominate genera were Hydrogenophaga,Pseudomonas,Bacteroides and Clostridium taking up 78% in one hundred. of positive clones.Phylogenetic dendrogram indicates that the relations among clones and isolated strains and their closest relatives presented certain distances;both Isolated 7（FJ439527） and Clone 86（EU834839） were closely related to Pseudomonas xiamenensis.

关 键 词：小麦秸秆 木质纤维素 好氧分解 复合系 多样性 

分 类 号：X172[环境科学与工程—环境科学]