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Ammonia oxidizing bacteria

Vincent Poot, Maaike Hoekstra, Mitchell A A Geleijnse, Mark C M van Loosdrecht, Julio Pérez
Partial nitritation was stably achieved in a bench-scale airlift reactor (1.5L) containing granular sludge. Continuous operation at 20 °C treating low-strength synthetic wastewater (50 mg N-NH4(+)/L and no COD) achieved nitrogen loading rates of 0.8 g N-NH4(+)/(L·d) during partial nitritation. The switch between nitrite-oxidizing bacteria (NOB) repression and NOB proliferation was observed when ammonium concentrations in the reactor were below 2-5 mg N-NH4(+)/L for DO concentrations lower than 4 mg O2/L at 20 °C...
October 11, 2016: Water Research
Wenjing Chen, Xiaohu Dai, Dawen Cao, Sha Wang, Xiaona Hu, Wenru Liu, Dianhai Yang
The partial nitrification (PN) performance and the microbial community variations were evaluated in a sequencing batch reactor (SBR) for 172 days, with the stepwise elevation of ammonium concentration. Free ammonia (FA) and low dissolved oxygen inhibition of nitrite-oxidized bacteria (NOB) were used to achieve nitritation in the SBR. During the 172 days operation, the nitrogen loading rate of the SBR was finally raised to 3.6 kg N/m(3)/d corresponding the influent ammonium of 1500 mg/L, with the ammonium removal efficiency and nitrite accumulation rate were 94...
October 20, 2016: Scientific Reports
Cristian Picioreanu, Julio Pérez, Mark C M van Loosdrecht
A three-dimensional (3-D) diffusion-reaction model was used to assess the effects of nitrifiers growing in cell clusters on the apparent oxygen half-saturation coefficients in activated sludge flocs. The model allows conciliation of seemingly contradictory reports by several research groups. Although intrinsic half-saturation coefficients (i.e., not affected by diffusion) show a better affinity for oxygen for ammonia oxidizing (AOB) than for nitrite oxidizing bacteria (NOB) (KO,AOB < KO,NOB), measurements in flocs often produced reversed apparent values (KO,AOB,app > KO,NOB,app), which can now be explained by the 3-D model with AOB and NOB microcolonies...
October 8, 2016: Water Research
Yun-Feng Duan, Xian-Wang Kong, Andreas Schramm, Rodrigo Labouriau, Jørgen Eriksen, Søren O Petersen
: Grassland cultivation can mobilize large pools of N in the soil, with a potential for N leaching and N2O emissions. Spraying with the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) before cultivation was simulated with soil columns where residue distribution corresponded to ploughing or rotovation, to study effects of soil-residue contact on N transformations. DMPP was sprayed on above-ground parts of ryegrass and white clover before incorporation. During a 42-day incubation, soil mineral N dynamics, potential ammonia oxidation (PAO) and denitrifying enzyme activity (DEA), nitrifier and denitrifier populations, and N2O emissions were investigated...
October 14, 2016: Applied and Environmental Microbiology
Xi Sun, Lusheng Zhu, Jinhua Wang, Jun Wang, Benying Su, Tong Liu, Cheng Zhang, Chong Gao, Yuting Shao
Ionic liquids (ILs) were considered as "green" solvents and have been used widely because of their excellent properties. But ILs are not as "green" as has been suggested, and the toxic effects of ILs on organisms have been shown in recent years. In the present study, the toxic effects of the IL 1-octyl-3-methylimidazolium tetrafluoroborate ([Omim]BF4) on soil enzyme activity and soil microbial communities at three different concentrations (1.0, 5.0 and 10.0mg/kg) and a control treatment over 40 days of incubation time (sampled on days 10, 20, 30 and 40) were examined under laboratory conditions...
October 11, 2016: Ecotoxicology and Environmental Safety
Cong-Cong Tang, Wei Zuo, Yu Tian, Ni Sun, Zhen-Wei Wang, Jun Zhang
This study investigated aeration rate (0, 0.2, 0.4 and 1.0L/min) effects on algal-bacterial symbiosis (ABS) and conventional activated sludge (CAS) systems while treating domestic wastewater in sequencing batch reactors. Experiment results showed that ABS system performed better on NH4(+)-N, total nitrogen and total phosphorus removal than CAS system, especially under lower aeration rate condition (0.2Lair/min), with removal efficiencies improvements of 18.90%, 12.45% and 46.66%, respectively. The mechanism study demonstrated that a favorable aeration rate reduction (half of traditional value in CAS system) could enhance algae growth but weaken hydraulic shear force, which contributed to the interactions between algae and sludge flocs and further stability of ABS system...
October 1, 2016: Bioresource Technology
Lan Wang, Ping Zheng, Ghulam Abbas, Yajuan Xing, Wei Li, Ru Wang, Liangwei Deng, Yunhui Lei, Dan Zheng, Yunhong Zhang
Nitrification is an acidifying process that requires the addition of external alkalinity because of the alkaliphilic nature of the most ammonia-oxidizing bacteria. In this study, aerobic activated sludge was used as inoculum in an internal loop air-lift reactor, which resulted in successful enrichment of acid-tolerant nitrifying (ACIN) sludge at pH 6.0 by sequential addition of tea orchard soil suspension. The results showed that ACIN sludge had a remarkable acid tolerant capability with a volumetric ammonia conversion rate of 1...
October 3, 2016: Journal of Environmental Management
Haryun Kim, Hee-Sung Bae, K Ramesh Reddy, Andrew Ogram
River tributaries are ecologically important environments that function as sinks of inorganic nitrogen. To gain greater insight into the nitrogen cycle (N-cycle) in these environments, the distributions and activities of microbial populations involved in the N-cycle were studied in riparian and stream sediments of the Santa Fe River (SFR) tributaries located in northern Florida, USA. Riparian sediments were characterized by much higher organic matter content, and extracellular enzyme activities, including cellobiohydrolase, β-d-glucosidase, and phenol oxidase than stream sediments...
September 30, 2016: Water Research
Bin Dong, Jie Tan, Yang Yang, Zishan Pang, Zhongtian Li, Xiaohu Dai
The primary goal of this study is to investigate ammonia removal, abundance of nitrifying bacteria and microbial community structures in a laboratory-scale integrated fixed film activated sludge (IFAS) reactor. The results of Illumina MiSeq sequencing based on 16S rRNA genes showed Proteobacteria and Bacteroidetes were the dominant phyla in both biofilm and suspended sludge samples in the IFAS reactor. The dominant ammonia-oxidizing bacteria (AOB) species was Nitrosomonas and the dominant nitrite-oxidizing bacteria species was Nitrospira...
September 2016: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Johannes F Imhoff
During the past decades, tremendous advances have been made in the possibilities to study the diversity of microbial communities in the environment. The development of methods to study these communities on the basis of 16S rRNA gene sequences analysis was a first step into the molecular analysis of environmental communities and the study of biodiversity in natural habitats. A new dimension in this field was reached with the introduction of functional genes of ecological importance and the establishment of genetic tools to study the diversity of functional microbial groups and their responses to environmental factors...
May 24, 2016: Microorganisms
Qingqing Feng, Lu Han, Xu Tan, Yali Zhang, Tianyi Meng, Jun Lu, Jie Lv
The Chishui River is the last undammed tributary of the upper Yangtze River, extends cross Sichuan, Yunnan and Guizhou provinces, and it is the significant water source of Maotai liquor, Southwest of China. We investigated microbial community of the Chishui River in the Maotai town section, because of deep relationship between the water and the most famous Chinese liquor, Maotai liquor. In this study, diversities of bacteria and archaea of four seasons were analyzed in two different sampling sites using a barcoded 16S rRNA gene-pyrosequencing approach...
December 2016: Current Microbiology
Rui Liu, Hangwei Hu, Helen Suter, Helen L Hayden, Jizheng He, Pauline Mele, Deli Chen
Most studies on soil N2O emissions have focused either on the quantifying of agricultural N2O fluxes or on the effect of environmental factors on N2O emissions. However, very limited information is available on how land-use will affect N2O production, and nitrifiers involved in N2O emissions in agricultural soil ecosystems. Therefore, this study aimed at evaluating the relative importance of nitrification and denitrification to N2O emissions from different land-use soils and identifying the potential underlying microbial mechanisms...
2016: Frontiers in Microbiology
Agnieszka Cydzik-Kwiatkowska, Paulina Rusanowska, Magdalena Zielińska, Katarzyna Bernat, Irena Wojnowska-Baryła
A technological system was developed for efficient nitrogen removal from real digester supernatant in a single reactor with shortened aeration to increase the economical aspects of wastewater treatment. The supernatant (600 mg TKN/L, low COD/N ratio of 2.2) was treated in batch reactors with aerobic granules (GSBRs) to test how one, two, or three non-aeration phases and acetate pulse feeding in the cycle affect the morphological and microbial properties of biomass. Introduction of one non-aeration phase in the cycle increased nitrogen removal efficiency by 11 % in comparison with constantly aerated GSBR...
September 23, 2016: Environmental Science and Pollution Research International
Marie Simonin, Agnès Richaume, Julien P Guyonnet, Audrey Dubost, Jean M F Martins, Thomas Pommier
Soils are facing new environmental stressors, such as titanium dioxide nanoparticles (TiO2-NPs). While these emerging pollutants are increasingly released into most ecosystems, including agricultural fields, their potential impacts on soil and its function remain to be investigated. Here we report the response of the microbial community of an agricultural soil exposed over 90 days to TiO2-NPs (1 and 500 mg kg(-1) dry soil). To assess their impact on soil function, we focused on the nitrogen cycle and measured nitrification and denitrification enzymatic activities and by quantifying specific representative genes (amoA for ammonia-oxidizers, nirK and nirS for denitrifiers)...
2016: Scientific Reports
Yun Zhang, Yue Zhao, Yanni Chen, Qian Lu, Mingxiao Li, Xueqin Wang, Yuquan Wei, Xinyu Xie, Zimin Wei
In this study, enriched ammonia-oxidizing bacteria (AOB) were acquired by domesticated cultivation, followed by inoculation into the co-composting of rice straw and chicken manure. The effect of inoculation on nitrogen loss, the succession of bacterial community and the correlation between the key bacteria and environmental factors were investigated. The results showed that inoculation could reduce ammonia emission and nitrogen loss by transforming ammonium into nitrite. Inoculation also increased the amount and abundance of bacterial community...
December 2016: Bioresource Technology
Catiane Pelissari, Cristina Ávila, Camila Maria Trein, Joan García, Rafael Dultra de Armas, Pablo Heleno Sezerino
The aim of this study was to characterize the nitrogen transforming bacterial communities within a partially saturated vertical subsurface flow constructed wetland (VF) treating urban wastewater in southern Brazil. The VF had a surface area of 3144m(2), and was divided into four wetland cells, out of which two were operated while the other two rested, alternating cycles of 30days. The nitrifying and denitrifying bacterial communities were characterized in wetland cell 3 (764m(2) surface area) over a period of 12months by using the FISH technique...
September 15, 2016: Science of the Total Environment
Yanan Yin, Wen Song, Jie Gu, Kaiyu Zhang, Xun Qian, Xin Zhang, Yajun Zhang, Yang Li, Xiaojuan Wang
This study investigated the effects of adding Cu(II) at two exposure levels (50 and 500mgkg(-1), i.e., Cu50 and Cu500 treatments, respectively) on the activity of ammonia-oxidizing microorganisms during dairy cattle manure composting. The results showed that the pH, NH4(+)-N, NO3(-)-N, and potential ammonia oxidation values were inhibited significantly by the addition of Cu(II). Furthermore, the abundances of the ammonia-oxidizing archaea (AOA) amoA gene and ammonia-oxidizing bacteria (AOB) amoA gene were determined by quantitative PCR, and their compositions were evaluated by denaturing gradient gel electrophoresis (DGGE)...
December 2016: Bioresource Technology
Moomen Soliman, Ahmed Eldyasti
Shortcut biological nitrogen removal is a non-conventional way of removing nitrogen from wastewater using two processes either nitrite shunt or deammonification. In the nitrite shunt process, the ammonia oxidation step stops at the nitrite stage, which is known as partial nitrification, then nitrite is directly reduced to nitrogen gas. Effective partial nitrification could be achieved by accumulating Ammonia Oxidizing Bacteria (AOB) and inhibiting Nitrite Oxidizing Bacteria (NOB). In this research, a novel control strategy has been developed to control the DO using the variable mixing regime in a suspended growth system using a Sequential Batch Reactor (SBR) in order to achieve a stable ammonia removal efficiency (ARE) and nitrite accumulation rate (NAR) at a high nitrogen loading rate (NLR)...
December 2016: Bioresource Technology
Wei-Li Du, Qiang Huang, Li-Li Miao, Ying Liu, Zhi-Pei Liu
Optimization of running parameters in a bioreactor requires detailed understanding of microbial community dynamics during the startup and running periods. Using a novel piggery wastewater treatment system termed "UASB + SHARON + ANAMMOX" constructed in our laboratory, we investigated microbial community dynamics using the Illumina MiSeq method, taking activated sludge samples at ~2-week intervals during a ~300-day period. Ammonia-oxidizing bacteria (AOB) were further investigated by quantification of AOB amoA genes and construction of gene clone libraries...
December 2016: AMB Express
Jun Zeng, Kai Lou, Cui-Jing Zhang, Jun-Tao Wang, Hang-Wei Hu, Ju-Pei Shen, Li-Mei Zhang, Li-Li Han, Tao Zhang, Qin Lin, Phillip M Chalk, Ji-Zheng He
Structural succession and its driving factors for nitrogen (N) cycling microbial communities during the early stages of soil development (0-44 years) were studied along a chronosequence in the glacial forelands of the Tianshan Mountain No.1 glacier in the arid and semi-arid region of central Asia. We assessed the abundance and population of functional genes affiliated with N-fixation (nifH), nitrification (bacterial and archaeal amoA), and denitrification (nirK/S and nosZ) in a glacier foreland using molecular methods...
2016: Frontiers in Microbiology
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