欢迎访问《环境科学学报》编辑部网站！

快速检索			高级检索

研究报告

Enrichment of a N-DAMO flora and the ecological factors for growth and metabolism

摘要：亚硝酸盐型甲烷厌氧氧化（N-DAMO）是某些微生物在厌氧条件下以甲烷为电子供体和唯一碳源还原亚硝酸盐（NO₂^-）为氮气（N₂）的过程，为解决废水生物脱氮碳源不足问题提供了新思路.然而，N-DAMO菌群生长缓慢，对环境要求严苛，富集培养难度大，工程应用困难.本文以湿地土壤为菌源，通过强化富集获得一个N-DAMO菌群，并研究了主要环境因子和生长因子对其生长代谢的影响.结果表明，该N-DAMO菌群的NO₂^-还原速率可达0.27 mmol·g^-1·d^-1，其最佳培养条件为35℃、pH 7.5、NO₂^-浓度为2.0 mmol·L^-1和甲烷分压为（P（CH₄））98 kPa等.少量添加维生素液、血红素和甜菜碱等生长因子，均能刺激菌群的代谢活性，使其NO₂^-还原速率分别提高1.32、1.22和1.96倍.本研究有助于进一步了解N-DAMO菌群的生理生态特性，为其工程应用提供参考.

Abstract：Nitrite-dependent anaerobic methane oxidation (N-DAMO) is a process in which anaerobic bacteria reduce nitrite (NO₂^-) to nitrogen (N₂) with the sole carbon source of methane as electron donors, providing a new idea for the nitrogen removal while cutting methane emission in biological wastewater treatment processes. However, N-DAMO bacteria are hard to be enriched in practical application, due to the slow growth and exacting environment. In the presented research, wetland soil as inoculum was enriched to get a N-DAMO flora which was further evaluated by various environment and growth factors to understand the ecophysiological characteristics of N-DAMO bacteria. The results showed that N-DAMO activity of the obtained flora was excellent with a specific nitrite reduction rate as high as 0.27 mmol·g^-1·d^-1. The feasible temperature, pH, NO₂^- density and methane partial pressure (P(CH₄)) for the N-DAMO flora were 35 ℃, 7.5, 2.0 mmol·L^-1 and 98 kPa, respectively. A trace of vitamins solution, hemachrome or betaine all could stimulate the metabolic activity of the N-DAMO flora with the specific nitrite reduction rate being enhanced by 1.32, 1.22 and 1.96 times, respectively.

Key words：nitrite-dependent anaerobic methane oxidation (N-DAMO) biological nitrogen removal microbial enrichment environmental factors growth factors