蠡河底泥中反硝化复合菌群富集及菌群结构研究

从无锡市滨湖区蠡河底泥中富集培养反硝化复合菌群,研究其在不同富集培养阶段TN、NO-3-N、NO-2-N、NH+4-N和COD动态变化,分析反硝化过程中气体释放总量、释放速率和成分,通过构建全长16S r DNA克隆文库研究其菌落结构.结果表明,反硝化复合菌群富集在阶段4时脱氮效果最佳,仅在9 h内,330 mg·L-1的TN负荷下,TN去除率达90.9%,NO-3-N去除率达100%,中间产物NO-2-N和NH+4-N积累量最少,分别为3.39 mg·L-1和16.64 mg·L-1,COD去除率达85%;释放气体260m L,气体主要成分为N2,同时还有少量的CH4和CO2等.富集培养反硝化复合菌群细菌属于Pseudomonadaceae科和Rhodocyclaceae科,为Proteobacteria门,OUT丰度分别为57.8%和31.6%,Pseudomonadaceae科是优势类群.

Enrichment and Characterization of A Denitrifying Bacteria Consortium from Lihe River's Sediment

A denitrifying bacteria consortium was enriched from LiHe River's sediment, the dynamics of total nitrogen (TN), nitrate (NO₃^--N), nitrite (NO₂^--N), ammonium (NH₄⁺-N) and COD at different enrichment cultivation stages were studied, and the total volume, the releasing rates and the composition of gas released during the denitrification process were analyzed. The full-length 16S rDNA clone library was constructed, enclosing the diversity of the denitrifying bacteria consortium. The results showed, in the enrichment phase 4, under the load of TN 330mg·L^-1, the best nitrogen removal effect was obtained, which the TN and NO₃^--N removal rates reached 90.9% and 100% within 9 hours, respectively. The accumulation amounts of NO₂^--N and NH₄⁺-N were merely 3.39 mg·L^-1 and 16.64 mg·L^-1. And the COD removal rate was 85%. The process released 260 mL of the compound gas, in which the main ingredient was N₂ associated with a small quantity of CH₄ and CO₂.The denitrifying bacteria consortium consisted of the family Pseudomonadaceae and the family Rhodocyclaceae, belonging to Proteobacteria phylum, in which the OUT abundances were 57.8% and 31.6%, respectively. The family Pseudomonadaceae was the predominant group.