Abstract:
The effects of different concentrations of biological nitrification inhibitors(methyl p-hydroxyphenylpropionate(MHPP), syringic acid(SA)) and chemical nitrification inhibitors(dicyanediamine(DCD), 3, 4- dimethyl-1H-pyrazole(DMPP)) on nitrifying bacteria were compared by sequential batch experiments. The results showed that these four nitrification inhibitors significantly inhibited the treatment efficiency of nitrite-oxidizing bacteria(NOB) at the optimal concentration, thereby reducing the nitrous nitrogen conversion rate by 71.31%-87.38%. The two chemical inhibitors(DCD and DMPP) had a certain inhibitory effect on the conversion rate of ammonia nitrogen, while the two biological inhibitors(MHPP and SA) did not significantly affect the conversion of NH4 +-N by ammonia-oxidizing microorganisms(AOB). The abundance of AOB(Nitrosomonas), the main functional bacterium in the nitrosation process, was not significantly affected, and the relative abundance of NOB(Nitrospira) was significantly suppressed, which was only 0.17%- 0.47%. Metagenomic analysis revealed that the molecular mechanism studies showed that the four inhibitors significantly inhibited the expression of nxrAB, a key gene closely related to NOB, and MHPP, SA and DCD did not significantly inhibit the key genes of AOB(amoCAB and hao). In addition, inhibitors further weakened the metabolic activity of NOB by reducing the abundance of pathways such as glyoxylate metabolism and amino acid transport(such as ABC transporters). The results showed that the nitrification inhibitor dosing strategy effectively achieved the directional inhibition of NOB,which laid a foundation for the stable operation of the subsequent low ammonia nitrosation process.
Key words:
low ammonia nitrogen,
nitrosation,
nitrification inhibitor
摘要：
通过序批式试验比较了不同投加量的生物硝化抑制剂〔对羟基苯丙酸甲酯（MHPP）、丁香酸（SA）〕与化学硝化抑制剂〔二氰二胺（DCD）、3，4-二甲基-1H-吡唑（DMPP）〕对硝化菌群的影响。结果表明，这4种硝化抑制剂在最适浓度下，显著抑制了亚硝酸盐氧化菌（NOB）的处理效能，从而降低了亚硝态氮转化率，抑制率达71.31%~87.38%。DCD、DMPP对氨氮转化率产生了一定的抑制作用，而MHPP、SA并未显著影响氨氧化菌（AOB）对NH4 +-N的转化。亚硝化过程的主要功能菌AOB（Nitrosomonas属）丰度未受显著影响，NOB（Nitrospira属）相对丰度被显著抑制，仅为0.17%~0.47%。宏基因组分析发现，分子机制研究表明，4种抑制剂显著抑制了与NOB密切相关的关键基因nxrAB的表达，其中MHPP、SA及DCD对AOB关键基因（amoCAB及hao）的抑制效果并不显著。此外，抑制剂还通过降低乙醛酸盐代谢、氨基酸转运（如ABC转运蛋白）等通路丰度，进一步削弱了NOB的代谢活性。结果表明，硝化抑制剂投加策略有效实现了对NOB的定向抑制，为后续低氨氮亚硝化过程的稳定运行打下了基础。
关键词:
低氨氮,
亚硝化,
硝化抑制剂
CLC Number:
Jiahao DENG, Tao XIANG, Xinyu CHENG, Wei LI. Effect and mechanism of nitrification inhibitors on the activity of nitrifying bacteria[J]. Industrial Water Treatment, 2026, 46(4): 131-139.
邓佳豪, 向韬, 程馨雨, 李微. 硝化抑制剂对硝化菌群的影响及作用机制[J]. 工业水处理, 2026, 46(4): 131-139.