Read by QxMD icon Read

Denitrifying bacteria

Laura Mancini, Stefania Marcheggiani, Cinzia Grasso, Cristina Romanelli, Antonio Mistretta, Marina Marranzano
Bacterial regrowth in water distribution systems results in deterioration of bacteriological quality of drinking water, as well as accelerated corrosion of the pipelines. The aim of the present study was to analyze the phenomena of colonization and bacterial regrowth in source water and in the water distribution systems of three distribution networks in the province of Catania (Sicily, Italy). The BART™ (Biological Activity Reaction Test) method was used, which is also capable of determining the potential aggressiveness of microbial species in water...
November 2016: Igiene e Sanità Pubblica
Romy Chakraborty, Hannah Woo, Paramvir Dehal, Robert Walker, Marcin Zemla, Manfred Auer, Lynne A Goodwin, Alexey Kazakov, Pavel Novichkov, Adam P Arkin, Terry C Hazen
Hexavalent Chromium [Cr(VI)] is a widespread contaminant found in soil, sediment, and ground water in several DOE sites, including Hanford 100 H area. In order to stimulate microbially mediated reduction of Cr(VI) at this site, a poly-lactate hydrogen release compound was injected into the chromium contaminated aquifer. Targeted enrichment of dominant nitrate-reducing bacteria post injection resulted in the isolation of Pseudomonas stutzeri strain RCH2. P. stutzeri strain RCH2 was isolated using acetate as the electron donor and is a complete denitrifier...
2017: Standards in Genomic Sciences
Yuanyuan Miao, Liang Zhang, Baikun Li, Qian Zhang, Simeng Wang, Yongzhen Peng
Intermittent aeration and bio-augmentation were integrated to enhance single-stage partial nitrification-anammox (SPN/A) stability over 235-day operational period treating low-strength sewage. The effect of bio-augmentation sludge (with different abundances of ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB)) was determined. Partial nitrification sludge based bio-augmentation increased the total nitrogen (TN) removal efficiency from 29.1% to 70%, followed by the nitrification sludge (from 38...
January 27, 2017: Bioresource Technology
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
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
Junwen Zhang, Teng Ma, Liang Feng, Yani Yan, Olusegun K Abass, Zhiqiang Wang, Huawei Cai
Studies have shown that arsenic is desorbed/released into groundwater as a result of bacterial reduction of As(V) and Fe(III). However, bacterial activities like sulfate reduction process can also reduce the content of arsenic in groundwater. In this study, we examined the effects of different biogeochemical processes (e.g. NO3(-) and SO4(2-) reduction) on arsenic, by investigating the chemical characteristics and bacterial community structure of groundwater in the Datong Basin, northern China. Along the groundwater flow path, arsenic concentration increased from <1 to 947...
February 6, 2017: Science of the Total Environment
Liang Fu, Jing Ding, Yong-Ze Lu, Zhao-Wei Ding, Raymond J Zeng
The co-culture system of denitrifying anaerobic methane oxidation (DAMO) and anaerobic ammonium oxidation (Anammox) has a potential application in wastewater treatment plant. This study explored the effects of permutation and combination of nitrate, nitrite, and ammonium on the culture enrichment from freshwater sediments. The co-existence of NO3(-), NO2(-), and NH4(+) shortened the enrichment time from 75 to 30 days and achieved a total nitrogen removal rate of 106.5 mg/L/day on day 132. Even though ammonium addition led to Anammox bacteria increase and a higher nitrogen removal rate, DAMO bacteria still dominated in different reactors with the highest proportion of 64...
February 6, 2017: Applied Microbiology and Biotechnology
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
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
Zhifei Li, Jianfeng Che, Jun Xie, Guangjun Wang, Ermeng Yu, Yun Xia, Deguang Yu, Kai Zhang
Biofilms can be used to improve the water quality in aquaculture ponds, and elucidating the process of microbial succession in biofilms would allow characterization of metabolic processes and permit optimization. In the present study, microbial succession of a biofilm growing on artificial substrata in a subtropical freshwater pond was investigated by high-throughput sequencing. Providing artificial substrata effectively reduced the concentrations of total nitrogen (TN) and total phosphorus (TP) in the pond...
January 26, 2017: FEMS Microbiology Letters
Lee P Hutt, Marcel Huntemann, Alicia Clum, Manoj Pillay, Krishnaveni Palaniappan, Neha Varghese, Natalia Mikhailova, Dimitrios Stamatis, Tatiparthi Reddy, Chris Daum, Nicole Shapiro, Natalia Ivanova, Nikos Kyrpides, Tanja Woyke, Rich Boden
Thiobacillus thioparus DSM 505(T) is one of first two isolated strains of inorganic sulfur-oxidising Bacteria. The original strain of T. thioparus was lost almost 100 years ago and the working type strain is Culture C(T) (=DSM 505(T) = ATCC 8158(T)) isolated by Starkey in 1934 from agricultural soil at Rutgers University, New Jersey, USA. It is an obligate chemolithoautotroph that conserves energy from the oxidation of reduced inorganic sulfur compounds using the Kelly-Trudinger pathway and uses it to fix carbon dioxide It is not capable of heterotrophic or mixotrophic growth...
2017: Standards in Genomic Sciences
Hexin Fei Jing Pan Deli Tong Linli Huang Long Yu Yafei Sun Shiyue Qi Yaoyao Huang
Dissolved oxygen (DO), removal of COD, TP and nitrogen in subsurface wastewater infiltration systems (SWISs)with/without intermittent aeration under different influent COD/N ratios were investigated. Aerobic conditions were effectively developed in 50 cm depth of the matrix and anoxic or anaerobic conditions were not changed in 80 and 110 cm depth by intermittent aeration, which encouraged nitrification. Increased influent COD/N ratio led to lower COD and nitrogen removal in conventional SWISs. Sufficient carbon source in high COD/N ratio influent promoted denitrification with intermittent aeration...
January 24, 2017: Water Environment Research: a Research Publication of the Water Environment Federation
Wei Xing, Jinlong Li, Yuan Cong, Wei Gao, Zhongjun Jia, Desheng Li
Autotrophic denitrification has attracted increasing attention for wastewater with insufficient organic carbon sources. Nevertheless, in situ identification of autotrophic denitrifying communities in reactors remains challenging. Here, a process combining micro-electrolysis and autotrophic denitrification with high nitrate removal efficiency was presented. Two batch reactors were fed organic-free nitrate influent, with H(13)CO3(-) and H(12)CO3(-) as inorganic carbon sources. DNA-based stable-isotope probing (DNA-SIP) was used to obtain molecular evidence for autotrophic denitrifying communities...
April 2017: Bioresource Technology
A Anisa Cokro, Yingyu Law, Rohan B H Williams, Yeshi Cao, Per H Nielsen, Stefan Wuertz
Enhanced biological phosphorus removal (EBPR) is a widely used process in wastewater treatment that requires anaerobic/aerobic or anaerobic/anoxic cycling. Surprisingly, phosphorus (P) release was observed in the presence of nitrate in the anoxic compartment of the activated sludge tank in a full-scale treatment plant with the Modified Ludzack Ettinger configuration. We therefore studied the potential of this full-scale activated sludge community to perform EBPR under anoxic/aerobic cycling. The polyphosphate accumulating organism (PAO) Candidatus Accumulibacter represented 3...
January 3, 2017: Water Research
Takahiro Watari, Trung Cuong Mai, Daisuke Tanikawa, Yuga Hirakata, Masashi Hatamoto, Kazuaki Syutsubo, Masao Fukuda, Ngoc Bich Nguyen, Takashi Yamaguchi
Conventional aerated tank technology is widely applied for post treatment of natural rubber processing wastewater in Southeast Asia; however, a long hydraulic retention time (HRT) is required and the effluent standards are exceeded. In this study, a downflow hanging sponge (DHS) reactor was installed as post treatment of anaerobic tank effluent in a natural rubber factory in South Vietnam and the process performance was evaluated. The DHS reactor demonstrated removal efficiencies of 64.2 ± 7.5% and 55.3 ± 19...
January 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Jamal Alikhani, Ahmed Al-Omari, Haydee De Clippeleir, Sudhir Murthy, Imre Takacs, Arash Massoudieh
In this study, the endogenous respiration rate and the observed biomass yield of denitrifying methylotrophic biomass were estimated through measuring changes in denitrification rates (DNR) as a result of maintaining the biomass under methanol deprived conditions. For this purpose, activated sludge biomass from a full-scale wastewater treatment plant was kept in 10-L batch reactors for 8 days under fully aerobic and anoxic conditions at 20 °C without methanol addition. To investigate temperature effects, another biomass sample was placed under starvation conditions over a period of 10 days under aerobic conditions at 25 °C...
January 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Ning Wang, Zhi-Zhou Chang, Xi-Mei Xue, Jian-Guang Yu, Xiao-Xia Shi, Lena Q Ma, Hong-Bo Li
Biochar application to agricultural soil is an appealing approach to mitigate nitrous oxide (N2O) and methane (CH4) emissions. However, the underlying microbial mechanisms are unclear. In this study, a paddy soil slurry was incubated anaerobically for 14d with biochar amendments produced from rice straw at 300, 500, or 700°C (B300, B500, and B700) to study their influences on greenhouse gas emissions. Illumina sequencing was used to characterize shift of soil bacterial and archaeal community composition. After peaking at day 1, N2O emission then sharply decreased to low levels while CH4 started to emit at day 3 then continually increased with incubation...
January 4, 2017: Science of the Total Environment
Hongliang Dai, Xiwu Lu, Lihong Peng, Xiang Li, Zheqin Dai
An efficient one-step domestication method with mixed electron acceptors and short time post-aeration was developed for the enrichment culture of denitrifying phosphorus removal sludge. The acclimation time, performance of nitrogen and phosphorus simultaneous removal and microbial community structure were investigated to reveal the difference among the obtained phosphorus removal sludge using different acclimation ways. Results showed that the proposed method with optimal proportion of nitrite and nitrate could significantly shorten domestication time (28 d) compared with the traditional two-step method (60 d), but exerted nearly no influence on the removal efficiency of nitrogen and phosphorus...
January 2, 2017: Environmental Technology
Artur Mielcarek, Joanna Rodziewicz, Wojciech Janczukowicz, Dorota Dabrowska, Slawomir Ciesielski, Arthur Thornton, Joanna Struk-Sokołowska
The study demonstrated that citric acid, as an organic carbon source, can improve denitrification in Anaerobic Sequencing Batch Biofilm Reactor (AnSBBR). The consumption rate of the organic substrate and the denitrification rate were lower during the period of the reactor's acclimatization (cycles 1-60; 71.5 mgCOD L(-1) h(-1) and 17.81 mgN L(-1) h(-1), respectively) than under the steady state conditions (cycles 61-180; 143.8 mgCOD L(-1) h(-1) and 24.38 mgN L(-1) h(-1)). The biomass yield coefficient reached 0...
December 22, 2016: Chemosphere
Junfeng Wang, Yuhui Wang, Junhong Bai, Zhaowei Liu, Xinshan Song, Dengming Yan, Asaminew Abiyu, Zhimiao Zhao, Denghua Yan
The constructed wetland coupled with biofilm-electrode reactor (CW-BER) is a novel technology to treat wastewater with a relatively high level of total inorganic nitrogen (TIN) concentration. The main objective of this study is to investigate the effects of C/Ns, TIN concentrations, current intensities, and pH on the removal of nitrogen in CW-BER; a control system (CW) was also constructed and operated with similar influent conditions. Results indicated that the current, inorganic carbon source and hydrogen generated by the micro-electric field could significantly improve the inorganic nitrogen removal with in CW-BER, and the enhancement of average removal rate on NH3-N, NO3-N, and TIN was approximately maintained at 5-28%, 5-26%, and 3-24%, respectively...
March 2017: Bioresource Technology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"