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Ammonia oxidizing bacteria

Jie Hou, Ling Xia, Tao Ma, Yiqing Zhang, Yiyong Zhou, Xugang He
This study aim to enhance nitrogen removal performance via shifting nitrogen removal pathway from nitrate to nitrite pathway. It was demonstrated that nitrite pathway was successfully and stably achieved in CWs by using modified intermittent aeration control with aeration 20min/non-aeration 100min and reducing DO concentration during aeration, nitrite in the effluent could accumulate to over 70% of the total oxidized nitrogen. Q-PCR analysis showed that nitrifying microbial communities were optimized under the alternating anoxic and aerobic conditions, ammonia oxidizing bacteria increased from 7...
February 10, 2017: Bioresource Technology
Jacynthe Masse, Cindy E Prescott, Sébastien Renaut, Yves Terrat, Sue J Grayston
The Athabasca Oil Sands deposit is one of the largest single oil deposits in the world. Following surface mining, companies are required to restore soil-like profiles that can support the previous land capabilities. The objective of this study was to assess if soil prokaryotic α- and β-diversity in oil-sands soils reconstructed 20-30 years previously, and planted to one of three vegetation types (coniferous or deciduous trees and grassland) were similar to those found in natural boreal-forest soils subject to wildfire disturbance...
February 17, 2017: Applied and Environmental Microbiology
Kai Li, Fang Fang, Han Wang, Chao Wang, Youpeng Chen, Jinsong Guo, Xixi Wang, Fuyang Jiang
To investigate the pathways of nitrogen (N) removal and N2O emission in a one-stage autotrophic N removal process during the non-aeration phase, biofilm from an intermittent aeration sequencing batch biofilm reactor (SBBR) and organic carbon-free synthetic wastewater were applied to two groups of lab-scale batch experiments in anaerobic conditions using a (15)N isotopic tracer and specific inhibitors, respectively. Then, the microbial composition of the biofilm was analysed using high-throughput sequencing...
February 16, 2017: Scientific Reports
Norisuke Ushiki, Masaru Jinno, Hirotsugu Fujitani, Toshikazu Suenaga, Akihiko Terada, Satoshi Tsuneda
Nitrite oxidation is an aerobic process of the nitrogen cycle in natural ecosystems, and is performed by nitrite-oxidizing bacteria (NOB). Also, nitrite oxidation is a rate-limiting step of nitrogen removal in wastewater treatment plants (WWTPs). Although Nitrospira is known as dominant NOB in WWTPs, information on their physiological properties and kinetic parameters is limited. Here, we report the kinetic parameters and inhibition of nitrite oxidation by free ammonia in pure cultures of Nitrospira sp. strain ND1 and Nitrospira japonica strain NJ1, which were previously isolated from activated sludge in a WWTP...
February 12, 2017: Journal of Bioscience and Bioengineering
Fabrizio Sabba, Cristian Picioreanu, Joshua P Boltz, Robert Nerenberg
Wastewater treatment plants can be significant sources of nitrous oxide (N2O), a potent greenhouse gas. While our understanding of N2O emissions from suspended-growth processes has advanced significantly, less is known about emissions from biofilm processes. Biofilms may behave differently due to their substrate gradients and microbial stratification. In this study, we used mathematical modeling to explore the mechanisms of N2O emissions from nitrifying and denitrifying biofilms. Our ammonia-oxidizing bacteria biofilm model suggests that N2O emissions from biofilm can be significantly greater than from suspended-growth systems...
February 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Michael Friedrich, Jose Jimenez, Amy Pruden, Jennifer H Miller, Jacob Metch, Imre Takács
Growth kinetics in activated sludge modelling (ASM) are typically assumed to be the result of intrinsic growth and decay properties and thus process parameters are deemed to be constant. The activity change in a microbial population is expressed in terms of variance of the active biomass fraction and not actual shifts in bacterial cellular activities. This approach is limited, in that it does not recognise the reality that active biomass is highly physiologically adaptive. Here, a strong correlation between maximum specific growth rate (μmax) and decay rate (be) of ordinary heterotrophic organisms was revealed in both low solids retention times (SRT) and high SRT activated sludge systems...
February 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Longqi Lang, Mathieu Pocquet, Bing-Jie Ni, Zhiguo Yuan, Mathieu Spérandio
The aim of this work is to compare the capability of two recently proposed two-pathway models for predicting nitrous oxide (N2O) production by ammonia-oxidizing bacteria (AOB) for varying ranges of dissolved oxygen (DO) and nitrite. The first model includes the electron carriers whereas the second model is based on direct coupling of electron donors and acceptors. Simulations are confronted to extensive sets of experiments (43 batches) from different studies with three different microbial systems. Despite their different mathematical structures, both models could well and similarly describe the combined effect of DO and nitrite on N2O production rate and emission factor...
February 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Rui Du, Shenbin Cao, Baikun Li, Shuying Wang, Yongzhen Peng
A novel DEAMOX system was developed for nitrogen removal from domestic wastewater and nitrate (NO3(-)-N) sewage in sequencing batch reactor (SBR). High nitrite (NO2(-)-N) was produced from NO3(-)-N reduction in partial-denitrification process, which served as electron acceptor for anammox and was removed with ammonia (NH4(+)-N) in domestic wastewater simultaneously. A 500-days operation demonstrated that the efficient and stable nitrogen removal performance could be achieved by DEAMOX. The total nitrogen (TN) removal efficiency was as high as 95...
February 4, 2017: Chemosphere
Bradley Young, Robert Delatolla, Turki Abujamel, Kevin Kennedy, Edith Laflamme, Alain Stintzi
The moving bed biofilm reactor (MBBR), operated as a post carbon removal system, requires long start-up times in comparison to carbon removal systems due to slow growing autotrophic organisms. This study investigates the use of carriers seeded in a carbon rich treatment system prior to inoculation in a nitrifying MBBR system to promote the rapid development of nitrifying biofilm in an MBBR system at temperatures between 6 and 8 °C. Results show that nitrification was initiated by the carbon removal carriers after 22 h of operation...
February 6, 2017: Bioprocess and Biosystems Engineering
Akihiko Terada, Sho Sugawara, Keisuke Hojo, Yuki Takeuchi, Shohei Riya, Willie F Harper, Tomoko Yamamoto, Megumi Kuroiwa, Kazuo Isobe, Chie Katsuyama, Yuichi Suwa, Keisuke Koba, Masaaki Hosomi
The goal of this study was to elucidate the mechanisms of N2O production from a bioreactor for partial nitrification (PN). Ammonia-oxidizing bacteria (AOB) enriched from a sequencing batch reactor (SBR) were subjected to N2O production pathway tests. The N2O pathway test was initiated by supplying an inorganic medium to ensure an initial NH4(+)-N concentration of 160 mg-N/L, followed by (15)NO2(-) (20 mg-N/L) and dual (15)NH2OH (each 17 mg-N/L) spikings to quantify isotopologs of gaseous N2O ((44)N2O, (45)N2O, and (46)N2O)...
February 6, 2017: Environmental Science & Technology
Catiane Pelissari, Miriam Guivernau, Marc Viñas, Samara Silva de Souza, Joan García, Pablo Heleno Sezerino, Cristina Ávila
The dynamics of the active microbial populations involved in nitrogen transformation in a vertical subsurface flow constructed wetland (VF) treating urban wastewater was assessed. The wetland (1.5m(2)) operated under average loads of 130gCODm(-2)d(-1) and 17gTNm(-2)d(-1) in Period I, and 80gCODm(-2)d(-1) and 19gTNm(-2)d(-1) in Period II. The hydraulic loading rate (HLR) was 375mmd(-1) and C/N ratio was 2 in both periods. Samples for microbial characterization were collected from the filter medium (top and bottom layers) of the wetland, water influent and effluent at the end of Periods I (Jun-Oct) and II (Nov-Jan)...
February 1, 2017: Science of the Total Environment
Junhao Qin, Chuxia Lin, Patrick Cheruiyot, Sandra Mkpanam, Nelisiwe Good-Mary Duma
Microcosm experiments were conducted to examine the effects of rainwater-borne H2O2 on inactivation of water-borne coliforms, oxidation of ammonia and nitrite, and degradation of organic pollutants in canal and urban lake water. The results show that the soluble iron in the investigated water samples was sufficiently effective for reaction with H2O2 in the simulated rainwater-affected stagnant water to produce OH (Fenton reaction), which inactivated coliform bacteria even at a H2O2 dose as low as 5 μM within just 1 min of contact time...
January 25, 2017: Chemosphere
Dong Wei, Keyi Zhang, Huu Hao Ngo, Wenshan Guo, Siyu Wang, Jibin Li, Fei Han, Bin Du, Qin Wei
In present study, the feasibility of partial nitrification (PN) process achievement and its greenhouse gas emission were evaluated in a sequencing batch biofilm reactor (SBBR). After 90days' operation, the average effluent NH4(+)-N removal efficiency and nitrite accumulation rate of PN-SBBR were high of 98.2% and 87.6%, respectively. Both polysaccharide and protein contents were reduced in loosely bound extracellular polymeric substances (LB-EPS) and tightly bound EPS (TB-EPS) during the achievement of PN-biofilm...
January 25, 2017: Bioresource Technology
Łukasz Jurczyk, Justyna Koc-Jurczyk
The application of multi-stage systems including biological step, for the treatment of leachate from municipal landfills, is economically and technologically justified. When microbial activity is utilized as 2nd stage of treatment, the task of 1st stage is to increase the bioavailability of organic matter. In this work, the effect of advanced oxidation process by Fenton's reagent for treatment efficiency of landfill leachate in the sequencing batch reactor was assessed. The quantitative dynamics of bacteria taking a part in ammonia removal process was evaluated by determination of number of DNA copies of 16S rRNA and amoA...
January 31, 2017: Waste Management
Marie Simonin, Jean M F Martins, Xavier Le Roux, Gaëlle Uzu, Aude Calas, Agnès Richaume
Titanium-dioxide nanoparticles (TiO2-NPs) are increasingly released in agricultural soils through, e.g. biosolids, irrigation or nanoagrochemicals. Soils are submitted to a wide range of concentrations of TiO2-NPs depending on the type of exposure. However, most studies have assessed the effects of unrealistically high concentrations, and the dose-response relationships are not well characterized for soil microbial communities. Here, using soil microcosms, we assessed the impact of TiO2-NPs at concentrations ranging from 0...
February 2, 2017: Nanotoxicology
Jing Chen, Ji-Dong Gu
In the present work, the diversity, community structures, and abundances of aerobic ammonia-oxidizing archaea (AOA) and bacteria (AOB), anaerobic ammonium-oxidizing (anammox) bacteria, and denitrifying anaerobic methane oxidization (n-damo) bacteria were unraveled in the bioturbated areas of the coastal Mai Po mangrove sediments. Results indicated that the bioturbation by burrowing in mangrove sediments was associated with higher concentration of NH4(+) but lower concentrations of both NO2(-) and NO3(-), and increase in diversity and richness of both AOA and AOB, but relatively lower diversity and richness of n-damo bacteria...
January 28, 2017: Microbial Ecology
Xi Lu, Zhixuan Yin, Dominika Sobotka, Kamil Wisniewski, Krzysztof Czerwionka, Li Xie, Qi Zhou, Jacek Makinia
The aim of the study was to determine the pH effects on nitrogen removal in the anammox-enriched granular sludge. The experimental data were extracted from a 4 L completely-mixed batch reactor with the granular sludge at different initial pH values (6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5) and constant temperature T = 30 °C. Simulations were run in GPS-X 6.4 using a comprehensive mechanistic model Mantis2. Two kinetic parameters, the maximum specific growth rates of ammonia oxidizing bacteria (AOB) and anammox bacteria, were optimized at different pH scenarios...
January 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Yu-Lian Huang, Zhao-Yong Sun, Xiao-Zhong Zhong, Ting-Ting Wang, Li Tan, Yue-Qin Tang, Kenji Kida
Digested residue remained at the end of a process for the production of fuel ethanol and methane from kitchen garbage. To develop a zero-emission process, the compostability of the digested residue was assessed to obtain an added-value fertilizer. Composting of the digested residue by adding matured compost and a bulking agent was performed using a lab-scale composting reactor. The composting process showed that volatile total solid (VTS) degradation mainly occurred during the first 13days, and the highest VTS degradation efficiency was about 27% at the end...
January 12, 2017: Waste Management
Bradley Young, Robert Delatolla, Kevin Kennedy, Edith Laflamme, Alain Stintzi
This study aims to investigate post carbon removal moving bed biofilm reactor (MBBR) nitrification through the transition from 20 °C to 1 °C and during through long term operation at 1 °C. Four pilot nitrifying MBBR reactors were operated at various ammonia loading rates to elucidate the temperature effects on ammonia removal rates, cell viability and bacterial communities. The transition from 20 °C to 1 °C and during long term operation at 1 °C were modeled using Arrhenius temperature correction coefficients...
January 5, 2017: Water Research
Chao Wang, Sitong Liu, Xiaochen Xu, Chuanqi Zhao, Fenglin Yang, Dong Wang
The objective of this study was to investigate the influence of extracellular polymeric substance (EPS) on the coupling effects between ammonia-oxidizing bacteria (AOB) and anaerobic ammonium-oxidizing (anammox) bacteria for the completely autotrophic nitrogen removal over nitrite (CANON) biofilm formation in a moving bed biofilm reactor (MBBR). Analysis of the quantity of EPS and cyclic diguanylate (c-di-GMP) confirmed that the contents of polysaccharides and c-di-GMP were correlated in the AOB sludge, anammox sludge, and CANON biofilm...
January 11, 2017: Applied Microbiology and Biotechnology
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