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Ammonia oxidizing bacteria

Depeng Wang, Bo Liu, Xinchun Ding, Xinbo Sun, Zi Liang, Shixiong Sheng, Lingfeng Du
Ammonia is widely distributed in sulfate-reducing bioreactor dealing with sulfate wastewater, which shows potential effect on the metabolic pathway of sulfate and ammonia. This study investigates the sulfate-reducing efficiency and microbial community composition in the sulfate-reducing EGSB reactor with the increasing ammonia loading. Results indicated that, compared with low ammonia loading (166-666 mg/L), the sulfate and organic matter removal efficiencies were improved gradually with the appropriate ammonia loading (1000-2000 mg/L), which increased from 63...
September 19, 2017: Applied Microbiology and Biotechnology
Shi-Peng Wang, Xiao-Zhong Zhong, Ting-Ting Wang, Zhao-Yong Sun, Yue-Qin Tang, Kenji Kida
Aerobic composting of distilled grain waste (DGW) at different initial pH values adjusted by CaO addition was investigated. Three pH-adjusted treatments with initial pH values of 4 (R1), 5 (R2) and 6 (R3) and a control treatment (R0) with a pH value of 3.5 were conducted simultaneously. The results showed that R0 had an unsuccessful start-up of composting. However, the pH-adjusted treatments produced remarkable results, with a relatively high initial pH being beneficial for the start-up. Within 65days of composting, the degradation of volatile solids (VS) and the physicochemical properties of R2 and R3 displayed similar tendencies, and both produced a mature end-product, while R1 exhibited a lower VS degradation rate, and some of its physicochemical properties indicated the end-product was immature...
September 8, 2017: Bioresource Technology
Guangjing Xu, Han Wang, Jun Gu, Nan Shen, Zheng Qiu, Yan Zhou, Yu Liu
This study developed an innovative A-B process for enhanced nutrients removal in municipal wastewater reclamation, in which a micro-aerated moving bed biofilm reactor served as A-stage and a step-feed sequencing batch reactor (SBR) as B-stage. In the A-stage, 55% of COD and 15% of ammonia nitrogen was removed, while more than 88% of the total nitrogen was removed via nitritation and denitritation, together with 93% of phosphorous removal at the B-stage where ammonia oxidizing bacteria activity was significantly higher than nitrite oxidizing bacteria activity...
September 12, 2017: Chemosphere
Haolong Wang, Mingu Kim, Kai Li, Yuanyuan Shao, Jesse Zhu, George Nakhla
A lab-scale fluidized bed bioreactor with high-density polyethylene as biofilm carrier media was operated to study partial nitrification performance with high ammonia concentrations. The system was run at nitrogen loading rates (NLR) from 1.2 to 4.8 kg N/(m(3)·d) with empty bed contact time (EBCT) of 2.0 hrs and 2.7 hrs and four different influent ammonia concentrations of 100, 200, 300 and 400 mg/L. Dissolved oxygen concentration and temperature were maintained around 1.3 mg/L and 35˚C, respectively. Stable partial nitrification was successfully achieved during the whole period with low effluent NO3-N concentration at less than 15 mg/L, due to effective suppression of nitrite-oxidizing bacteria activity (NOB) at high concentrations of free ammonia (5...
September 15, 2017: Environmental Technology
Xiaoliang Jiang, Yujing Wu, Guihua Liu, Wenzhi Liu, Bei Lu
Ammonia-oxidizing archaea (AOA) and bacteria (AOB) play important roles in regulating the nitrification process in lake ecosystems. However, the relative effects of climate, catchment land use and local conditions on the sediment ammonia-oxidizing communities in lakes remain unclear. In this study, the diversity and abundance of AOA and AOB communities were investigated in ten Yangtze lakes by polymerase chain reaction (PCR), clone library and quantitative PCR techniques. The results showed that the abundances of both AOA and AOB in bare sediments were considerably but not significantly higher than those in vegetated sediments...
September 13, 2017: AMB Express
Pamela Y Camejo, Jorge Santo Domingo, Katherine D McMahon, Daniel R Noguera
The recently discovered comammox bacteria have the potential to completely oxidize ammonia to nitrate. These microorganisms are part of the Nitrospira genus and are present in a variety of environments, including biological nutrient removal (BNR) systems. However, the physiological traits within and between comammox and nitrite-oxidizing bacterium (NOB)-like Nitrospira species have not been analyzed in these ecosystems. In this study, we identified Nitrospira strains dominating the nitrifying community of a sequencing batch reactor (SBR) performing BNR under microaerobic conditions...
September 2017: MSystems
Co Thi Kinh, Shohei Riya, Masaaki Hosomi, Akihiko Terada
A membrane-aerated biofilm reactor (MABR) provides a counter-current substrate diffusion geometry in which oxygen is supplied from a gas-permeable membrane on which a biofilm is grown. This study hypothesized that an MABR would mitigate NO and N2O emissions compared with those from a conventional biofilm reactor (CBR). Two laboratory-scale reactors, representing an MABR and CBR, were operated by feeding synthetic industrial wastewater. The surficial nitrogen removal rate for the MABR [4.51±0.52g-N/(m(2)day)] was higher than that for the CBR [3...
August 12, 2017: Bioresource Technology
Bin Ma, Lan Yang, Qilin Wang, Zhiguo Yuan, Yayi Wang, Yongzhen Peng
Inactivation and adaptation of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) to free nitrous acid (FNA) was investigated. Batch test results showed that AOB and NOB were inactivated when treated with FNA. After an 85-day operating period, AOB in a continuous pre-denitrification reactor did not adapt to the FNA that was applied to treat some of the return activated sludge. In contrast, NOB did adapt to FNA. NOB activity in the seed sludge was only 11% of the original activity after FNA batch treatment, at 0...
August 15, 2017: Bioresource Technology
Linda Hink, Pawel Lycus, Cécile Gubry-Rangin, Åsa Frostegård, Graeme W Nicol, James I Prosser, Lars R Bakken
Ammonia oxidising bacteria (AOB) are thought to emit more nitrous oxide (N2 O) than ammonia oxidising archaea (AOA), due to their higher N2 O yield under oxic conditions and denitrification in response to oxygen (O2 ) limitation. We determined the kinetics of growth and turnover of nitric oxide (NO) and N2 O at low cell densities of Nitrosomonas europaea (AOB) and Nitrosopumilus maritimus (AOA) during gradual depletion of TAN (NH3  + NH4(+) ) and O2 . Half-saturation constants for O2 and TAN were similar to those determined by others, except for the half-saturation constant for ammonium in N...
September 11, 2017: Environmental Microbiology
Brett L Mellbye, Eva Spieck, Peter J Bottomley, Luis A Sayavedra-Soto
The genomes of many bacteria that participate in nitrogen cycling through the process of nitrification contain putative genes associated with acyl-homoserine lactone (AHL) quorum sensing (QS). AHL QS or bacterial cell-cell signaling is a method of bacterial communication and gene regulation and may be involved in nitrogen oxide fluxes or other important phenotypes in nitrifying bacteria. Here, we carried out a broad survey of AHL production in nitrifying bacteria in three steps. First, we analyzed the evolutionary history of AHL synthase and AHL receptor homologs in sequenced genomes and metagenomes of nitrifying bacteria to identify AHL synthase homologs in ammonia-oxidizing bacteria (AOB) of the genera Nitrosospira and nitrite-oxidizing bacteria (NOB) of the genera Nitrococcus, Nitrobacter, and Nitrospira Next, we screened cultures of both AOB and NOB cultures with uncharacterized AHL synthase genes and AHL synthase-negative nitrifiers by bioassay...
September 8, 2017: Applied and Environmental Microbiology
Féline L Assémien, Thomas Pommier, Jean T Gonnety, Jonathan Gervaix, Xavier Le Roux
The moist savanna zone covers 0.5 × 10(6) km(2) in West Africa and is characterized by very low soil N levels limiting primary production, but the ecology of nitrifiers in these (agro)ecosystems is largely unknown. We compared the effects of six agricultural practices on nitrifier activity, abundance and diversity at nine sites in central Ivory Coast. Treatments, including repeated fertilization with ammonium and urea, had no effect on nitrification and crop N status after 3 to 5 crop cycles. Nitrification was actually higher at low than medium ammonium level...
August 31, 2017: Scientific Reports
Josh Smeraldi, Rajagopalan Ganesh, Turaj Hosseini, Leila Khatib, Betty H Olson, Diego Rosso
  The production of zinc nanomaterial has increased significantly over the past several years and, as a result, nanoparticles have navigated their way into wastewater streams. The transportation and toxicity of zinc nanomaterial within the wastewater treatment processes is not well known. In this study, the zinc nanomaterial and its fate were characterized in an activated sludge treatment process. The tests performed included batch studies to evaluate abiotic and biotic removal, toxicity studies to evaluate inhibition to coliform and nitrifying bacteria, and bioreactor studies to evaluate impact on operating parameters...
September 1, 2017: Water Environment Research: a Research Publication of the Water Environment Federation
Qiang Kong, Xiao He, Shuai-Shuai Ma, Yu Feng, Ming-Sheng Miao, Yuan-da Du, Fei Xu, Qian Wang
The performance and microbial community changes of an activated sludge sequencing batch reactor were evaluated after exposure to trimethoprim for 51days. The average chemical oxygen demand, ammonia nitrogen, phosphorus efficiencies were 88.6%±0.56%, 90.47%±0.29% and 64.25%±1.12%, respectively. The protein and polysaccharide contents increased with increasing trimethoprim concentration to protect the cells from the unfavorable conditions. The chemical composition of extracellular polymeric substances increased...
November 2017: Bioresource Technology
K Dimitri Kits, Christopher J Sedlacek, Elena V Lebedeva, Ping Han, Alexandr Bulaev, Petra Pjevac, Anne Daebeler, Stefano Romano, Mads Albertsen, Lisa Y Stein, Holger Daims, Michael Wagner
Nitrification, the oxidation of ammonia (NH3) via nitrite (NO2(-)) to nitrate (NO3(-)), is a key process of the biogeochemical nitrogen cycle. For decades, ammonia and nitrite oxidation were thought to be separately catalysed by ammonia-oxidizing bacteria (AOB) and archaea (AOA), and by nitrite-oxidizing bacteria (NOB). The recent discovery of complete ammonia oxidizers (comammox) in the NOB genus Nitrospira, which alone convert ammonia to nitrate, raised questions about the ecological niches in which comammox Nitrospira successfully compete with canonical nitrifiers...
September 14, 2017: Nature
Vojtech Kouba, Dana Vejmelková, Eva Proksova, Helene Wiesinger, Martin Concha, Petr Dolejs, Jakub Hejnic, Pavel Jenicek, Jan Bartacek
Partial nitritation/anammox can provide energy-efficient nitrogen removal from the main stream of municipal wastewater. The main bottleneck is the growth of nitrite oxidizing bacteria (NOB) at low temperatures (<15 °C). To produce effluent suitable for anammox, real municipal wastewater after anaerobic pre-treatment was treated by enriched ammonium oxidizing bacteria (AOB) in suspended sludge SBR at 12 °C. NOB were continually washed out using Aerobic Duration Control Strategy (ADCS). Solids retention time was set to 9-16 days...
August 28, 2017: Environmental Science & Technology
Dhritikshama Roy, John McEvoy, Mark Blonigen, Maria Amundson, Eakalak Khan
The abundance of ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB) was investigated in full-scale two-stage trickling filters (TF) and moving bed bioreactor (MBBR) treating municipal wastewater. Biofilm samples were collected for 17months from nitrifying TF (NTF), biochemical oxygen demand TF (BTF), and MBBR media. The abundance of AOA and AOB was determined using a quantitative PCR approach targeting the ammonia monooxygenase subunit A gene of archaea and bacteria. AOA were dominant in the NTF and MBBR, while AOB dominated in the BTF...
November 2017: Bioresource Technology
Qianwen Sui, Chao Jiang, Dawei Yu, Meixue Chen, Junya Zhang, Yawei Wang, Yuansong Wei
Due to high-strength of organic matters, nutrients and pathogen, swine wastewater is a major source of pollution to rural environment and surface water. A sequencing-batch membrane bioreactor (SMBR) system with an automatic control strategy was developed for high-strength swine wastewater treatment. Short-cut nitrification and denitrification (SND) was achieved at nitrite accumulation rate of 83.6%, with removal rates of COD, NH4(+)-N and TN at 95%, 99% and 93%, respectively, at reduced HRT of 6.0 d and TN loading rate of 0...
May 8, 2017: Journal of Hazardous Materials
Sabrina Copelli, Massimo Raboni, Marco Derudi, Giuseppe Nano, Vincenzo Torretta
Polluted air streams can be purified using biological treatments such as biotrickling filtration, which is one of the most widely accepted techniques successfully tuned to treat a wide variety of exhausted gaseous streams coming from a series of industrial sectors such as food processing, flavor manufacturers, rendering, and composting. Since the degradation of a pollutant occurs at standard pressure and temperature, biotrickling filtration, whether compared with other more energy-demanding chemical-physical processes of abatement (such as scrubbing, catalytic oxidation, regenerative adsorption, incineration, advanced oxidation processes, etc...
August 22, 2017: Environmental Science and Pollution Research International
Zhongwei Wang, Mark C M van Loosdrecht, Pascal E Saikaly
Salinity can affect the performance of biological wastewater treatment in terms of nutrient removal. The effect of salt on aerobic granular sludge (AGS) process in terms of granulation and nutrient removal was examined in this study. Experiments were conducted to evaluate the effect of salt (15 g/L NaCl) on granule formation and nutrient removal in AGS system started with flocculent sludge and operated at DO of 2.5 mg/L (phase I). In addition, experiments were conducted to evaluate the effect of gradually increasing the salt concentration (2...
August 13, 2017: Water Research
Yoshiaki Tanabe, Kazuya Arashiba, Kazunari Nakajima, Yoshiaki Nishibayashi
Molybdenum-catalyzed conversion of molecular dinitrogen into ammonia under ambient reaction conditions has been achieved by using a proton source generated in situ from the ruthenium-catalyzed oxidation of water in combination with visible light and a photosensitizer. The preset reaction system is considered as a new model for the nitrogen fixation by photosynthetic bacteria.
August 17, 2017: Chemistry, An Asian Journal
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