腐殖酸和产甲烷抑制剂对厌氧污泥发酵产氢效能的影响

为提高厌氧污泥的发酵产氢能力，采用间歇培养方式考察了不同产甲烷抑制剂与腐殖酸联合作用对厌氧污泥发酵葡萄糖产氢效能的影响，并通过Illumina MiSeq测序揭示了微生物群落结构的变化规律.结果表明，在葡萄糖初始浓度为500 mg·L^-1条件下，经过120 h的连续培养后，对照的累计产氢量为1.2 mL，存在明显的耗氢现象.当加入0.02%氯仿（V/V）、0.04%氯仿（V/V）或2-溴乙酸磺酸钠（10 mmol·L^-1）后，耗氢现象得到有效控制，它们的累计产氢量分别为15.7、13.2和9.4 mL.当向发酵系统同时加入产甲烷抑制剂和腐殖酸后，可以显著提高厌氧污泥的产氢效能.其中，0.02%氯仿和腐殖酸联合作用的促进效果最佳，其累计产氢量和最大产氢速率（R_max）分别达到了17.4 mL和0.24 mL·L^-1.相反，当替硝唑作为产甲烷抑制剂时，仍然存在耗氢现象.Illumina MiSeq测序结果表明，发酵系统中优势菌群的相对丰度存在显著差异.在对照系统中，Ottowia、Ignavibacterium、Nitrospira、Saccharibacteria_genera_incertae_sedis和Terrimona为优势菌群，其相对丰度为2.2%~4.2%.当0.02%氯仿和腐殖酸加入发酵系统后，Ottowia和Saccharibacteria_genera_incertae_sedis的相对丰度较对照分别增加了11.9%和31.8%，而Nitrospira的含量显著减少.

Effects of humic acid and methanogenesis inhibitors on hydrogen production performance by anaerobic sludge

To improve the hydrogen production capacity of anaerobic sludge, the effects of humic acid combining with different methanogenesis inhibitors on hydrogen production from glucose were investigated by batch culture. The shift of microbial community structure was also revealed by Illumina MiSeq sequencing. The results showed that the cumulative hydrogen production in control was 1.2 mL after 120 h cultivation under the initial glucose concentration of 500 mg·L^-1 condition. In addition, an obvious hydrogen consumption phenomenon could be observed in control. When chloroform of 0.02% (V/V), 0.04% (V/V) or 2-bromoethanesulphonate (10 mmol·L^-1) were added to the fermentation systems, the hydrogen consumption was effectively inhibited. Their cumulative hydrogen production were 15.7, 13.2, and 9.4 mL, respectively. Both methanogenesis inhibitors and humic acid were added to the fermentation systems led to the hydrogen production significantly enhanced. Among them, the maximum efficiency of hydrogen production was obtained in humic acid combining with 0.02% chloroform fermentation system. The cumulative hydrogen production and maximum hydrogen production rate (R_max) in this system reached 17.4 mL and 0.24 mL·L^-1, respectively. On the contrary, when tinidazole was used as methanogenesis inhibitor, hydrogen consumption could still be observed. Illumina MiSeq sequencing showed that there were significant differences in the relative abundance of dominant microbial groups in different fermentation systems. The dominant microbial community were Ottowia, Ignavibacterium, Saccharibacteria_genera_incertae_sedis and Terrimonas with relative abundance of 2.2%~4.2% in control. When 0.02% chloroform and humic acid were added to fermentation system, the relative abundance of Ottowia and Saccharibacteria_genera_incertae_sedis were increased by 11.9% and 31.8%, respectively. However, the number of Nitrospira was significantly reduced.