Characteristics of a Novel Aerobic Denitrifying Bacterium, Enterobacter cloacae Strain HNR
Characteristics of a Novel Aerobic Denitrifying Bacterium, Enterobacter cloacae Strain HNR
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新型好氧反硝化细菌阴沟肠杆菌 HNR 菌株的特性
DOI：
10.1007/s12010-015-1920-8
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发表时间：
2016-03-01
影响因子：
3
通讯作者：
Tian, Meng
中科院分区：
文献类型：
--
作者：
Guo, Long-Jie;Zhao, Bin;Tian, Meng
从活性污泥中分离到一株新的好氧厌氧微生物HNR，经16SrRNA序列分析，鉴定为阴沟肠杆菌（Enterobacter cloeanitis）。葡萄糖被认为是菌株HNR最有利的碳源。在NO3（-）-N初始浓度为110 mg/L时，细菌的最大生长速率（μ max）为0.283 h（-1）。30 h内，NO3（-）-N几乎全部被好氧去除，平均去除速率为4.58 mg N L（-1）h（-1）。氮平衡分析表明，在该工艺中，约70.8%的NO3（-）-N以气体形式被去除，只有20.7%转化为生物质。GC-MS分析结果表明，N2是好氧反硝化的最终产物。与好氧反硝化过程相关的硝酸还原酶和亚硝酸还原酶活性分别为0.0688和0.0054U/mg蛋白。因此，证明了菌株HNR将NO3（-）还原为N2的好氧反硝化作用。最佳脱氮条件为：C/N = 13，pH = 8，摇床转速127 rpm，温度30 ° C。这些结果表明，E.在好氧条件下，Clobacillus菌株HNR在废水处理中实现硝酸盐的去除具有潜在的应用价值。
A novel aerobic denitrifier strain HNR, isolated from activated sludge, was identified as Enterobacter cloacae by16S rRNA sequencing analysis. Glucose was considered as the most favorable C-source for strain HNR. The logistic equation well described the bacterial growth, yielding a maximum growth rate (μmax) of 0.283 h(-1) with an initial NO3 (-)-N concentration of 110 mg/L. Almost all NO3 (-)-N was removed aerobically within 30 h with an average removal rate of 4.58 mg N L(-1) h(-1). Nitrogen balance analysis revealed that proximately 70.8 % of NO3 (-)-N was removed as gas products and only 20.7 % was transformed into biomass. GC-MS result indicates that N2 was the end product of aerobic denitrification. The enzyme activities of nitrate reductase and nitrite reductase, which are related to the process of aerobic denitrification, were 0.0688 and 0.0054 U/mg protein, respectively. Thus, the aerobic denitrification of reducing NO3 (-) to N2 by strain HNR was demonstrated. The optimal conditions for nitrate removal were C/N ratio 13, pH value 8, shaking speed 127 rpm and temperature 30 °C. These findings show that E. cloacae strain HNR has a potential application on wastewater treatment to achieve nitrate removal under aerobic conditions.