Low-dose Ultraviolet-A irradiation selectively eliminates nitrite oxidizing bacteria for mainstream nitritation
Low-dose Ultraviolet-A irradiation selectively eliminates nitrite oxidizing bacteria for mainstream nitritation
复制标题
低剂量紫外线A照射选择性消除亚硝酸氧化细菌，实现主流亚硝化
DOI：
10.1016/j.chemosphere.2020.128172
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发表时间：
2020-12-01
期刊：
影响因子：
8.8
通讯作者：
Zhang, Liqiu
中科院分区：
文献类型：
--
作者：
Chu, Zhaorui;Huang, Xiaoyu;Zhang, Liqiu
亚硝化是目前公认的主流亚硝酸盐分流或部分亚硝化/厌氧氨氧化（PN/A）的瓶颈。在这里，我们提出了一种新的方法来选择性地消除亚硝酸盐氧化细菌（NOB）的主流亚硝化低剂量紫外线（UVA）照射。结果表明，在0.87 μ E·L ~（-1）·s ~（-1）的UVA照射下，10 d内可迅速达到主流亚硝酸化，亚硝酸盐积累率（NO_2 ~--N/（NO_2 ~--N + NOT-N）× 100%）稳定在80%以上。微生物群落分析表明，两个典型的NOB种群（Nitrospira和Ca.在UVA辐照反应器中，对照反应器中检测到的亚硝化菌（Nitrotoga）被有效地抑制，而氨氧化细菌（AOB）的亚硝化单胞菌属保持在类似的水平。细胞内活性氧（ROS）分析表明，在UVA照射下，NOB优势污泥比AOB优势污泥更容易产生细胞内活性氧，从而导致NOB的失活和清除。此外，在UVA照射反应器中发现的微藻的量可以通过在光合作用期间产生ROS来帮助抑制NOB。简而言之，在这项研究中提出的UVA照射方法被证明是有前途的NOB抑制可靠的主流亚硝化。(C)2020爱思唯尔有限公司保留所有权利。
Nitritation is currently known as a bottleneck for mainstream nitrite shunt or partial nitritation/anammox (PN/A). Here we propose a new approach to selectively eliminate nitrite oxidizing bacteria (NOB) for mainstream nitritation by low-dose ultraviolet-A (UVA) irradiation. The results showed that mainstream nitritation was rapidly achieved within 10 days with UVA irradiation at the dose of 0.87 mu E L-1 s(-1), and nitrite accumulation ratio (NO2--N/(NO2--N + NOT-N) x100%) stabilized over 80%. Microbial community analysis revealed that two typical NOB populations (Nitrospira and Ca. Nitrotoga) detected in the control reactor were suppressed efficiently in UVA irradiation reactor, whereas the Nitrosomonas genus of ammonium oxidizing bacteria (AOB) remained at similar level. Intracellular reactive oxygen species (ROS) analysis indicated that NOB-dominant sludge tends to generate more intracellular ROS compared with AOB-dominant sludge in the presence of UVA, leading to the inactivation and elimination of NOB. Additionally, amounts of microalgae found in UVA irradiation reactor could help to suppress NOB by generating ROS during photosynthesis. Briefly, the UVA irradiation approach proposed in this study was shown to be promising in NOB suppression for reliable mainstream nitritation. (C) 2020 Elsevier Ltd. All rights reserved.