不同富集和分离培养条件下的含酚废水处理生物膜微生物群落结构与活性比较分析

Comparative Analysis of Community Structure and Activity of Wastewater Treatment Biofilm Cultivated Under Different Conditions

采用Biolog和变性梯度凝胶电泳(DGGE)技术研究了不同苯酚浓度培养对焦化废水处理厂反硝化池生物膜样品中微生物群落结构和代谢类型的影响。DGGE结果表明,不同浓度苯酚和不同培养方式富集培养后,细菌16SrDNA的部分条带分布谱形发生改变,还有部分条带只受到了苯酚浓度变化的影响;富集培养过程中由于碳源组成相对焦化废水简单,DGGE条带所代表的优势微生物多样性有所降低。Biolog试验结果表明,生物膜样本的细菌群落代谢能力最强;低浓度苯酚富集后的样品能利用的底物碳源类型最丰富。对Biolog试验结果的主成分分析显示,相同浓度苯酚富集培养后的细菌群落代谢功能多样性相似,但从DGGE结果看出其结构组成产生了变化。富集培养使样品微生物群落的代谢功能发生改变,低浓度的苯酚富集增加了群落中微生物的代谢类型。而不同条件获得的分离物其苯酚降解能力的初步分析也表明,富集与分离条件对苯酚降解菌的分离能力和得到的菌株特性具有差别。

The effect of phenol concentration on the structure and function of microbial communities, which were cultured in different conditions using coking wastewater biofilm as seeding, was investigated by Biolog and denaturing gradient gel electrophoresis （DGGE） methods. The less number of bands of cultivated sam- ples on the denaturing gradient gel electrophoresis fingerprint of 16S rRNA gene indicated reduction of diversity after enrichment and cultivation. Some bands on the DGGE gel were significantly influenced by the phenol concentration in medium. The results of Biolog showed that the original biofilm sample had the highest substrate utility capacity as measured by average well color development （AWCD）. But low concentration of phenol enriched sample S7 showed more diverse activity on the utility of Carboxylic acids. The principal component analysis （PCA） of Biolog data revealed that the metabolic patterns were similar when using the same phenol concentration, although the sample S7 much less similar to other cultivated samples. These results suggested that the enrichment and cultivation with phenol supplemented decreased the diversity and also changed the metabolic function of the microbial community. Lower phenol concentration increased the microbial community metabolic activity. The phenol degrading capacity of isolates from each samples indicated that the enrichment and cultivation condition had changed the type and property of cultruable bacteria. Based on these results, we concluded that the different microorganisms will be isolated under different cultivation condition.