Shenzhen Engineering Laboratory of Microalgal Bioenergy, Harbin Institute of Technology (Shenzhen), 518055, Shenzhen, China.
Shenzhen Engineering Laboratory of Microalgal Bioenergy, Harbin Institute of Technology (Shenzhen), 518055, Shenzhen, China.
Environ Pollut. 2019 Dec;255(Pt 2):113258. doi: 10.1016/j.envpol.2019.113258. Epub 2019 Sep 18.
Ammonia oxidation is the rate-limiting step in nitrification process and dominated by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). In the present study, a highly enriched culture of AOA was obtained from urban polluted water in Shahe River, Shenzhen, China. The optimum growth conditions were identified by orthogonal analysis as 37 °C, with pH 7.0 and initial ammonia concentration of 1.0 mM. Under these conditions, the highest abundance of AOA was obtained as 4.6 × 10 copies/ng DNA. Growth of AOA in polluted river water showed significant reduction in ammonia concentration in AOA-enriched cultures without antibiotics after 10 days of incubation, while synchronous increase in nitrate concentration was up to 12.7 mg/L. However, AOA-enriched by antibiotic showed insignificant changes in ammonia or nitrite concentration. This study showed that AOB play an important role in ammonia oxidation of polluted river water, and AOA alone showed insignificant changes in ammonia or nitrite concentrations. Therefore, the ammonia oxidation performance of natural water could not be improved by adding high concentration AOA bacterial liquid.
氨氧化是硝化过程的限速步骤，主要由氨氧化细菌（AOB）和氨氧化古菌（AOA）主导。本研究从中国深圳沙河受污染的城市水中获得了高度富集的 AOA 培养物。通过正交分析确定了最佳生长条件为 37°C，pH 值为 7.0，初始氨浓度为 1.0 mM。在这些条件下，AOA 的丰度最高可达 4.6×10 拷贝/ng DNA。在没有抗生素的情况下，AOA 在受污染河水培养物中的生长在 10 天的孵育后显著降低了氨浓度，同时硝酸盐浓度同步增加到 12.7 mg/L。然而，用抗生素富集的 AOA 对氨或亚硝酸盐浓度没有明显变化。本研究表明，AOB 在受污染河水的氨氧化中发挥重要作用，而单独的 AOA 对氨或亚硝酸盐浓度没有明显变化。因此，向天然水中添加高浓度 AOA 细菌液并不能提高氨氧化性能。
