两种碳源条件下好氧颗粒污泥中细菌的群落结构研究

发布时间：2017-12-27 23:13

本文关键词：两种碳源条件下好氧颗粒污泥中细菌的群落结构研究　出处：《武汉理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：好氧颗粒污泥具有沉降性能优异、微生物浓度较高等特点,在污水脱氮除磷方面具有良好的应用潜力。已有研究表明,碳源的组成对颗粒污泥的脱氮除磷性能具有重要影响,但目前关于碳源对颗粒污泥影响的研究主要集中在对污泥理化性质和内部结构的影响方面,缺少对不同碳源条件下颗粒污泥中细菌,尤其是功能菌组成的系统研究。本文通过构建16S rDNA文库,研究了分别以葡萄糖、黄水作为碳源的两个序批式反应器(SBR)中好氧颗粒污泥的菌群结构,并对不同碳源条件下颗粒污泥中细菌的多样性和功能菌进行了比较和分析,主要研究内容及结果如下:(1)分别构建了两种碳源条件下好氧颗粒污泥的16S rDNA文库,均得到155个阳性克隆子。酶切分型结果表明,2个文库可分别划分为53个(葡萄糖文库)和90个(黄水文库)可分类操作单元(OTU)。葡萄糖文库的物种丰富度指数Schao1为89.2,黄水文库的为183.2。黄水培养的颗粒污泥中细菌的多样性远高于葡萄糖培养的颗粒污泥,说明进水基质对颗粒污泥中细菌的多样性有显著影响。(2)对两文库中克隆子数大于1的OTU进行了测序,分别获得26条(葡萄糖文库)和30条(黄水文库)16S rDNA序列。序列分析结果表明,黄水文库中已测序的细菌分别来自Proteobacteria、Acidobacteria、Chloroflexi和Bacteroidetes 4个门,而葡萄糖文库中除了这4个门的菌以外还检测到了Candidatus Saccharibacteria门和Planctomycetes门的菌。(3)从属的水平上讲,2个文库的菌群组成有很大的差异。葡萄糖文库中只有一个能鉴定到属的优势类群(Candidatus Accumulibacter菌),该类群占已测序克隆的23.4%;其它优势类群均与已知菌属同源性较低,它们均占已测序克隆数的5.5%~8.6%。黄水文库的优势菌为Thauera、Dechloromonas、Nitrosomonas和Hydrogenophaga,分别占已测序克隆数的16.8%、8.4%、8.4%和5.3%;此外,还有少量与已知菌属同源性较低的菌(占已测序克隆的5.3%~8.4%)。2个文库优势菌的组成差异显著,说明碳源对颗粒污泥的菌群结构有重要影响。(4)葡萄糖文库和黄水文库中均检测到了与除磷和反硝化有关的细菌。2个文库中的聚磷菌均为Candidatus Accumulibacter菌,但葡萄糖文库中该菌所占的比例(23.4%)高于黄水文库(8.4%)。葡萄糖文库中只检测到一种反硝化菌(Denitratisoma-like菌),而黄水文库中与反硝化有关的菌包括Thauera、Dechloromonas、Zoogloea以及和1个与Sulfuritalea亲缘关系较近的细菌类群。此外,黄水文库中反硝化菌在已测序克隆中所占的比例(29.5%)高于葡萄糖文库(7.0%)。这些差异可能是由于2个反应器N、P负荷不同引起的。(5)黄水文库中检测到了可能具有降解芳香族化合物功能、氨氧化功能或能够分泌胞外多聚物(EPS)的菌,而在葡萄糖文库中没有检测到具有这些功能的菌,说明黄水培养的颗粒污泥细菌的功能多样性更丰富,更适合用来处理成分复杂的有机废水。
[Abstract]:Aerobic granular sludge has the characteristics of excellent settling property and high microbial concentration, and has good application potential in the aspect of nitrogen and phosphorus removal in sewage. Studies have shown that the composition of carbon source has important influence on the performance of nitrogen and phosphorus removal of granular sludge, but the current research on the effects of carbon source on the granular sludge mainly concentrated on the influence of physicochemical properties and internal structure of sludge, lack of bacteria in granular sludge under different carbon source conditions, especially the system of functional bacteria. In this paper, by constructing the 16S rDNA library, was studied by glucose, water was used as carbon source two sequencing batch reactor (SBR) flora in aerobic granular sludge, and the diversity and function of bacteria granular sludge with different carbon source conditions were compared and analyzed. The main research contents and the results are as follows: (1) were constructed with 16S rDNA Library of aerobic granular sludge under the condition of two kinds of carbon sources, obtained 155 positive clones. RFLP results show that 2 libraries can be divided into 53 (glucose Library) and 90 (yellow Library) classification operation unit (OTU). The species richness index of Schao1 glucose was up to 89.2, water was up to 183.2. The water culture of the diversity of bacteria in granular sludge is much higher than that of granular sludge on glucose, and that water matrix on bacterial diversity in granular sludge had significant effect. (2) of two library clones number is greater than 1 OTU were sequenced, respectively (26 glucose Library) and 30 (yellow Library) 16S rDNA sequence. The results of sequence analysis showed that the bacteria in the water have been sequencing library respectively from Proteobacteria, Acidobacteria, Chloroflexi and Bacteroidetes 4, while glucose library besides these 4 door bacteria were detected Candidatus Saccharibacteria and Planctomycetes gates of bacteria. (3) from the level of the subordinate, there is a great difference in the composition of the bacteria in the 2 library. Only one of the glucose libraries can identify the dominant group (Candidatus Accumulibacter), which accounts for 23.4% of the cloned clones, and the other dominant groups are low homology with the known bacteria. They all account for 5.5%~8.6% of the number of sequenced clones. The dominant bacteria yellow library was Thauera and Dechloromonas, Nitrosomonas and Hydrogenophaga, respectively, accounted for 16.8% of the number of sequenced clones, 8.4%, 8.4% and 5.3%; in addition, there are a small number of known bacteria with low homology bacteria (representing sequencing cloned 5.3%~8.4%). There were significant differences in the composition of the dominant bacteria in the 2 libraries, indicating that the carbon source had an important influence on the structure of the bacterial flora of the granular sludge. (4) glucose library and library water were detected with phosphorus removal and denitrification of bacteria. PAOs 2 libraries were Candidatus Accumulibacter bacteria, but bacteria accounted for the proportion of the glucose Library (23.4%) is higher than that of yellow Library (8.4%). Glucose library only detected a denitrifying bacteria (Denitratisoma-like bacteria), and yellow library and denitrifying bacteria including related bacterial taxa near Thauera, Dechloromonas, Zoogloea, and 1 Sulfuritalea and genetic relationship. In addition, denitrifying bacteria yellow library occupied in the sequenced clones in the library (29.5%) is higher than the proportion of glucose (7%). These differences may be caused by the different loads of the 2 reactors, N and P. (5) was detected in the library may have aromatic compound degrading function, ammonia oxidation function or secretion of extracellular polymeric substances (EPS) of the bacteria, but not in the glucose library were detected with these features that water cultured bacteria, granular sludge bacterial functional diversity is more abundant, more suitable for the treatment of organic wastewater by complex components.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703;X172

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