厌氧氨氧化启动过程Anammox菌富集规律和差异分析

Enrichment regulation of anammox bacteria in the anammox start-up process

摘要:

为明确厌氧氨氧化反应器启动过程中Anammox菌的富集规律，采用荧光原位杂交 (FISH) 和实时荧光定量PCR (q-PCR) 分析技术，对未添加填料、添加多面空心球以及添加竹炭的3个UASB反应器厌氧氨氧化启动过程中Anammox菌的增长规律进行分析。研究表明，Anammox菌的相对数量和绝对数量均随着启动时间呈逐渐递增趋势，在稳定运行阶段的第123天，无填料、多面空心球和竹炭反应器中Anammox菌分别占总细菌的23.3%、32.6%和43.7%，单位VSS污泥中Anammox菌16S rRNA基因拷贝数分别为(25.64±2.76)×107、(47.12±2.76)×107和(577.99±27.25)×107 拷贝数g–1 VSS。竹炭反应器中Anammox菌最大生长率和最短倍增时间分别为0.064 d-1和10.8 d，最大生长率分别是无填料和多面空心球反应器的1.78倍和1.88倍。因此，填料添加特别是竹炭的添加可极大地促进Anammox菌的选择性生长和繁殖。FISH和q-PCR 分析技术均适用于Anammox菌的富集规律研究，但因其检测目标存在差异，造成两者表征结果有所不同。

Abstract:

To study the enrichment regulation of anammox bacteria during the whole start-up process of anammox reaction, two reactors with addition of carries of Spherical Plastic (SP) and Bamboo Charcoal (BC) and one without carrier (CK) were used to start anammox reaction. Then FISH and q-PCR analyses for the growth of all anammox bacteria were conducted during the operational process. The results indicate that the number of anammox bacteria in all reactors increased with time during the whole start-up process, which was consistent with the removal rate of ammonium and nitrite. On day 123 of stable phase, the percent of anammox cells in the sludge of CK, SP and BC accounted for 23.3%, 32.6% and 43.7%, respectively. The number of anammox bacteria 16S rRNA gene copies was (25.64±2.76)×107, (47.12±2.76)×107 and (577.99±27.25)×107 copies g–1 VSS in the sludge of CK, SP and BC, respectively. Carrier addition could dramatically increase enrichment of anammox bacteria. BC addition significantly increased the anammox bacteria number in the UASB reactor which resulted in the acceleration of the anammox start-up process. In addition, the max specific growth rate and the minimum doubling time were 0.064 d–1 and 10.8 d in BC reactor. The max specific growth rate of anammox bacteria in BC reactor was 1.78 times and 1.88 times greater than that in CK and SP reactor, respectively. Therefore, the FISH and q-PCR analyses were suitable for determining the enrichment regulation of anammox bacteria during the start-up time, while a bit of differences in results existed between the two analytical methods due to the difference in analysis targets.