Ziembińska Aleksandra, Raszka Anna, Truu Jaak, Surmacz-Górska Joanna, Miksch Korneliusz
Environmental Biotechnology Department, Faculty of Power and Environmental Engineering, The Silesian University of Technology, Gliwice, Poland.
Pol J Microbiol. 2007;56(2):119-27.
Wastewater treatment based on activated sludge is known to be one of the most effective and popular wastewater purification methods. An estimation of microbial community variability in activated sludge allows us to observe the correlation between a particular bacterial group's appearance and the effectiveness of the removal of chemical substances. This research is focused on microbial community temporal changes in membrane bioreactors treating wastes containing a high level of ammonia nitrogen. Samples for this study were collected from two membrane bioreactors with an activated sludge age of 12 and 32 days, respectively. The activated sludge microbial community was adapted for the removal of ammonia nitrogen up to a level of 0.3 g NH4(+) - N g/VSS/d (VSS - volatile suspended solids). The methods - denaturing gradient gel electrophoresis (DGGE) based on 16S rRNA gene PCR products and fluorescent in situ hybridization (FISH) with 16S rRNA gene probes - revealed significant differences in the microbial community structure in the two bioreactors, caused mainly by a difference in sludge age. According to the results obtained in this study, a bioreactor with a sludge age of 12 days is characterized by a much higher microbial community diversity than a bioreactor with a sludge age of 32 days. Interestingly, the appearance of particular species of nitrifying bacteria was constant throughout the experiment in both bioreactors. Changes occured only in the case of the Nitrosomonas oligotropha lineage bacteria. This study demonstrates that the bacterial community of bioreactors operating with different sludge ages differs in total community structure. Nevertheless, the changeability of the bacterial community structure did not have any influence on the efficiency of nitrification.
基于活性污泥的废水处理是已知最有效且最受欢迎的废水净化方法之一。对活性污泥中微生物群落变异性的评估使我们能够观察特定细菌群体的出现与化学物质去除效果之间的相关性。本研究聚焦于处理含有高浓度氨氮废物的膜生物反应器中微生物群落的时间变化。本研究的样本分别从两个活性污泥龄期为12天和32天的膜生物反应器中采集。活性污泥微生物群落适应了将氨氮去除至0.3 g NH4(+) - N g/VSS/d（VSS - 挥发性悬浮固体）的水平。基于16S rRNA基因PCR产物的变性梯度凝胶电泳（DGGE）方法以及使用16S rRNA基因探针的荧光原位杂交（FISH）方法显示，两个生物反应器中微生物群落结构存在显著差异，主要是由污泥龄期的差异导致的。根据本研究获得的结果，污泥龄期为12天的生物反应器的微生物群落多样性远高于污泥龄期为32天的生物反应器。有趣的是，在整个实验过程中，两个生物反应器中特定种类的硝化细菌的出现情况是恒定的。仅在寡营养亚硝化单胞菌谱系细菌的情况下发生了变化。本研究表明，运行污泥龄期不同的生物反应器的细菌群落在总群落结构上存在差异。然而，细菌群落结构的可变性对硝化效率没有任何影响。
