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Ammonia oxidizing bacteria

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https://www.readbyqxmd.com/read/28628989/pollutant-removal-and-microorganism-evolution-of-activated-sludge-under-ofloxacin-selection-pressure
#1
Qiang Kong, Xiao He, Yu Feng, Ming-Sheng Miao, Qian Wang, Yuan-da Du, Fei Xu
An activated sludge sequencing batch reactor (SBR) was fed with synthetic wastewater containing ofloxacin (OFL) for 52days to study the overall performance of the SBR, the characteristics of extracellular polymeric substances (EPS) and the bacterial community shift. Removal efficiencies of chemical oxygen demand, ammonia nitrogen, phosphorus and OFL were maintained at 90%, 96%, 80% and 65%, respectively. The EPS contents increased with increasing OFL concentration because more EPS was secreted to protect cells from OFL damage...
June 14, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28624728/nitrite-production-from-urine-for-sulfide-control-in-sewers
#2
Min Zheng, Zhiqiang Zuo, Yizhen Zhang, Yujia Cui, Qian Dong, Yanchen Liu, Xia Huang, Zhiguo Yuan
Most commonly used methods for sewer sulfide control involves dosing chemical agents to wastewater, which incurs high operational costs. Here, we propose and demonstrate a cost-effective and environmentally attractive approach to sewer sulfide control through urine separation and its subsequent conversion to nitrite prior to intermittent dosage to sewers. Urine collected from a male toilet urinal was fed to laboratory-scale sequencing batch reactors. The reactors stably converted roughly 50% of the nitrogen in urine to nitrite, with high abundance (at 17...
May 23, 2017: Water Research
https://www.readbyqxmd.com/read/28622648/long-term-sustainability-of-microbial-induced-caco3-precipitation-in-aqueous-media
#3
Daniella Gat, Zeev Ronen, Michael Tsesarsky
Microbially induced CaCO3 precipitation (MICP) via urea hydrolysis is an emerging technique for soil amelioration, building materials rehabilitation and pollutants sequestration amongst other various environmental applications. The successful application of MICP requires the sustainability of the precipitated CaCO3; to which the fate of ammonia, the main by-product of ureolysis, is potentially significante. Ammonia volatilization and biological ammonia oxidation both induce a pH decrease, which, in turn, might cause CaCO3 dissolution...
June 7, 2017: Chemosphere
https://www.readbyqxmd.com/read/28619110/effect-of-aspartic-acid-and-glutamate-on-metabolism-and-acid-stress-resistance-of-acetobacter-pasteurianus
#4
Haisong Yin, Renkuan Zhang, Menglei Xia, Xiaolei Bai, Jun Mou, Yu Zheng, Min Wang
BACKGROUND: Acetic acid bacteria (AAB) are widely applied in food, bioengineering and medicine fields. However, the acid stress at low pH conditions limits acetic acid fermentation efficiency and high concentration of vinegar production with AAB. Therefore, how to enhance resistance ability of the AAB remains as the major challenge. Amino acids play an important role in cell growth and cell survival under severe environment. However, until now the effects of amino acids on acetic fermentation and acid stress resistance of AAB have not been fully studied...
June 15, 2017: Microbial Cell Factories
https://www.readbyqxmd.com/read/28606550/chitosan-mediated-synthesis-of-flowery-cuo-and-its-antibacterial-and-catalytic-properties
#5
Gownolla Malegowd Raghavendra, Jeyoung Jung, Dowan Kim, Jongchul Seo
In the current investigation, CuO with a flower-like morphology has been successfully synthesized in situ in a chitosan medium (0.0015gmL(-1)) from copper nitrate (Cu(NO3)2·3H2O) and ammonia solution via a facile microwave-induced method. The as-prepared CuO was characterized by SEM, TEM, EDX, XRD, FTIR and TGA. The antibacterial activity of the flower-CuO against Escherichia coli was examined by analyzing colony forming units, and it was proved that the flower-CuO was able to kill >99% bacteria. Further, the flower-CuO exhibited excellent catalytic activity towards the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4...
September 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28599226/partial-nitrification-performance-and-mechanism-of-zeolite-biological-aerated-filter-for-ammonium-wastewater-treatment
#6
Yongyuan Yang, Zhenguo Chen, Xiaojun Wang, Lei Zheng, Xiaoyang Gu
A zeolite biological aerated filter (ZBAF) with continuous feeding was successfully applied for achieving stable partial nitrification. Excellent nitrite accumulation (higher than 98.0%) and high nitrite/nitrate production rate (NPR) (approximately 0.760kg/m(3)/d) were obtained with increase influent ammonium concentration from 250 to 550mg/L within a nitrogen loading rate (NLR) of 0.854-1.200kg/m(3)/d. Owning to the adsorption of zeolite to ammonium, free ammonia (FA) concentration could remain at an appropriate range for inhibition of nitrite oxidizing bacteria (NOB) and dominance of ammonia-oxidizing bacteria (AOB), which should be responsible for the excellent partial nitrification realized in ZBAF...
May 29, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28593806/a-nitrogen-removal-system-to-limit-water-exchange-for-recirculating-freshwater-aquarium-using-dhs-usb-reactor
#7
Nur Adlin, Norihisa Matsuura, Yuki Ohta, Yuga Hirakata, Shinya Maki, Masashi Hatamoto, Takashi Yamaguchi
This study proposes a biological nitrogen removal system for freshwater aquaria consisting of a down-flow hanging sponge (DHS) and an up-flow sludge blanket (USB). DHS-USB systems can perform nitrification and denitrification simultaneously, reducing ammonia (NH3) and nitrate (NO3(-)) toxicity in the water. The performance of the system was evaluated using on-site fresh water aquaria at ambient temperature (23-34°C) over 192 days. NH3 and nitrite (NO2(-)) were maintained at a detection limit of 0.01 mg N L(-1) and NO3(-) was maintained below 10 mg N L(-1), despite limited water exchange...
June 13, 2017: Environmental Technology
https://www.readbyqxmd.com/read/28585561/nitrogen-transformations-in-modern-agriculture-and-the-role-of-biological-nitrification-inhibition
#8
REVIEW
Devrim Coskun, Dev T Britto, Weiming Shi, Herbert J Kronzucker
The nitrogen (N)-use efficiency of agricultural plants is notoriously poor. Globally, about 50% of the N fertilizer applied to cropping systems is not absorbed by plants, but lost to the environment as ammonia (NH3), nitrate (NO3(-)), and nitrous oxide (N2O, a greenhouse gas with 300 times the heat-trapping capacity of carbon dioxide), raising agricultural production costs and contributing to pollution and climate change. These losses are driven by volatilization of NH3 and by a matrix of nitrification and denitrification reactions catalysed by soil microorganisms (chiefly bacteria and archaea)...
June 6, 2017: Nature Plants
https://www.readbyqxmd.com/read/28571872/achieving-partial-nitrification-by-inhibiting-the-activity-of-nitrospira-like-bacteria-under-high-do-conditions-in-an-intermittent-aeration-reactor
#9
Peng Bao, Shuying Wang, Bin Ma, Qiong Zhang, Yongzhen Peng
It is generally accepted that a low dissolved oxygen (DO) concentration is more beneficial for achieving partial nitrification than high-DO. In this study, partial nitrification was not established under low-DO conditions in an intermittent aeration reactor for treating domestic wastewater. During the operational period of low-DO conditions (DO: 0.3±0.14mg/L), stable complete nitrification was observed. The abundance of Nitrospira-like bacteria, which were the major nitrite-oxidizing bacteria, increased from 1...
June 2017: Journal of Environmental Sciences (China)
https://www.readbyqxmd.com/read/28562229/effect-of-chromium-vi-on-the-multiple-nitrogen-removal-pathways-and-microbial-community-of-aerobic-granular-sludge
#10
Xiao-Ying Zheng, Dan Lu, Ming-Yang Wang, Wei Chen, Gan Zhou, Yuan Zhang
The frequent appearance of Cr(VI) significantly impacts the microbial metabolism in wastewater. In this study, long-term effects of Cr(VI) on microbial community, nitrogen removal pathways and mechanism of aerobic granular sludge (AGS) were investigated. AGS had strong resistance ability to 1.0 mg/L Cr(VI). 3.0 mg/L Cr(VI) increased the heterotrophic-specific ammonia uptake rate (HSAUR) and heterotrophic-specific nitrate uptake rate (HSNUR) transiently, whereas 5.0 mg/L Cr(VI) sharply decreased the specific ammonia uptake rate (SAUR), specific nitrate uptake rate (SNUR) and simultaneous nitrification denitrification rate (SNDR)...
June 12, 2017: Environmental Technology
https://www.readbyqxmd.com/read/28551535/microbial-community-shifts-in-a-farm-scale-anaerobic-digester-treating-swine-waste-correlations-between-bacteria-communities-associated-with-hydrogenotrophic-methanogens-and-environmental-conditions
#11
Kyungjin Cho, Seung Gu Shin, Woong Kim, Joonyeob Lee, Changsoo Lee, Seokhwan Hwang
Microbial community structure in a farm-scale anaerobic digester treating swine manure was investigated during three process events: 1) prolonged starvation, and changes of 2) operating temperature (between meso- and thermophilic) and 3) hydraulic retention time (HRT). Except during the initial period, the digester was dominated by hydrogenotrophic methanogens (HMs). The bacterial community structure significantly shifted with operating temperature and HRT but not with long-term starvation. Clostridiales (26...
May 25, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28549327/achievement-performance-and-characteristics-of-microbial-products-in-a-partial-nitrification-sequencing-batch-reactor-as-a-pretreatment-for-anaerobic-ammonium-oxidation
#12
Heng Dong, Keyi Zhang, Xiao Han, Bin Du, Qin Wei, Dong Wei
This study was carried out to evaluate achievement, performance and characteristics of microbial products in a partial nitrification sequencing batch reactor as a pretreatment for anaerobic ammonium oxidation (anammox). After 100 days long-term operation, the effluent NO2(-)-N/NH4(+)N ratio of the reactor was average at 1.3 and NO3(-)-N concentration was low by controlling low dissolved oxygen (DO) concentration, which was considered as the ideal influent for anammox. Specific oxygen uptake rate (SOUR) implied that (SOUR)NH4 and (SOUR)NO2 of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in sludge changed from 21...
May 20, 2017: Chemosphere
https://www.readbyqxmd.com/read/28544522/metagenomic-potential-for-and-diversity-of-n-cycle-driving-microorganisms-in-the-bothnian-sea-sediment
#13
Olivia Rasigraf, Julia Schmitt, Mike S M Jetten, Claudia Lüke
The biological nitrogen cycle is driven by a plethora of reactions transforming nitrogen compounds between various redox states. Here, we investigated the metagenomic potential for nitrogen cycle of the in situ microbial community in an oligotrophic, brackish environment of the Bothnian Sea sediment. Total DNA from three sediment depths was isolated and sequenced. The characterization of the total community was performed based on 16S rRNA gene inventory using SILVA database as reference. The diversity of diagnostic functional genes coding for nitrate reductases (napA;narG), nitrite:nitrate oxidoreductase (nxrA), nitrite reductases (nirK;nirS;nrfA), nitric oxide reductase (nor), nitrous oxide reductase (nosZ), hydrazine synthase (hzsA), ammonia monooxygenase (amoA), hydroxylamine oxidoreductase (hao), and nitrogenase (nifH) was analyzed by blastx against curated reference databases...
May 23, 2017: MicrobiologyOpen
https://www.readbyqxmd.com/read/28543691/emergent-macrophytes-modify-the-abundance-and-community-composition-of-ammonia-oxidizers-in-their-rhizosphere-sediments
#14
Dayong Zhao, Xiaowei He, Rui Huang, Wenming Yan, Zhongbo Yu
Ammonia oxidation is a crucial process in global nitrogen cycling, which is catalyzed by the ammonia oxidizers. Emergent plants play important roles in the freshwater ecosystem. Therefore, it is meaningful to investigate the effects of emergent macrophytes on the abundance and community composition of ammonia oxidizers. In the present study, two commonly found emergent macrophytes (Zizania caduciflora and Phragmitas communis) were obtained from freshwater lakes and the abundance and community composition of the ammonia-oxidizing prokaryotes in the rhizosphere sediments of these emergent macrophytes were investigated...
May 22, 2017: Journal of Basic Microbiology
https://www.readbyqxmd.com/read/28540424/screening-and-optimizing-of-inhibitors-for-ammonia-oxidizing-bacteria-in-sediments-of-malodorous-river
#15
Jianhua Wang, Yan He, Jin Zhu, Huimin Guan, Minsheng Huang
The proper use of selective ammonia-oxidizing archaea (AOA) and/or ammonia-oxidizing bacteria (AOB) inhibitors is critical to distinguish AOA and AOB contribution. In this research, three inhibitors including ampicillin, dicyandiamide (DCD), and allylthiourea (ATU) were examined mainly focusing on inhibiting dosage, adaptability, and effects. The results showed that the optimized inhibitory dosage of ampicillin, DCD, and ATU was separately 1.5 g L(-1), 1 mM, and 25 μM. Among the three inhibitors, ATU exhibited the strongest and persistent inhibition effects and resulted in up to 90% inhibition in the AOB-enriched culture...
May 24, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28526785/effects-of-arginine-on-growth-virulence-gene-expression-and-stress-tolerance-by-streptococcus-mutans
#16
Brinta Chakraborty, Robert A Burne
Streptococcus mutans is a common constituent of oral biofilms and a primary etiologic agent of human dental caries. The bacteria associated with dental caries have a potent ability to produce organic acids from dietary carbohydrates and to grow and metabolize in acidic conditions. In contrast, many commensal bacteria produce ammonia through the arginine deiminase system (ADS), which moderates the pH of oral biofilms. Arginine metabolism by the ADS is a significant deterrent to the initiation and progression of dental caries...
May 19, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28523826/occurrence-and-abundance-of-ammonia-oxidizing-archaea-and-bacteria-from-the-surface-to-below-the-water-table-in-deep-soil-and-their-contributions-to-nitrification
#17
Lei Zheng, Xue Zhao, Guibing Zhu, Wei Yang, Chao Xia, Tao Xu
Using molecular biology methods (qualitative and quantitative PCR), we determined the occurrence and abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) from a dry inland soil in Basel, Switzerland, and from the riparian zone of Baiyangdian Lake, China. We also determined the contributions of these microorganisms to ammonia oxidization at different depths based on the nitrification rate. The number of archaeal amoA genes (the key functional gene in AOA) was larger than the number of bacterial amoA genes in each sample, suggesting a dominant role for the AOA amoA gene in environments with a low ammonium concentration...
May 19, 2017: MicrobiologyOpen
https://www.readbyqxmd.com/read/28521169/heterotrophic-ammonia-and-nitrate-bio-removal-over-nitrite-hanbon-performance-and-microflora
#18
Wei Li, Zhao-Yang Cai, Zi-Jun Duo, Yao-Feng Lu, Ke-Xin Gao, Ghulam Abbas, Meng Zhang, Ping Zheng
A novel Heterotrophic Ammonia and Nitrate Bio-removal Over Nitrite (Hanbon) process, combining Short Nitrate Reduction (SNR) with Anaerobic Ammonia Oxidation (Anammox), was developed in a lab-scale continuous up-flow reactor. The substrate effects were investigated to characterize the performance of Hanbon process, and the corresponding microflora information was also revealed. Our results showed that the optimal substrate ratio of NH4(+)-N:NO3(-)-N:COD for the Hanbon process was 0.65:1:2.2. The volumetric nitrogen removal rate was up to 9...
May 13, 2017: Chemosphere
https://www.readbyqxmd.com/read/28509546/growth-of-nitrosococcus-related-ammonia-oxidizing-bacteria-coincides-with-extremely-low-ph-values-in-wastewater-with-high-ammonia-content
#19
Alexandra Fumasoli, Helmut Bürgmann, David G Weissbrodt, George F Wells, Karin Beck, Joachim Mohn, Eberhard Morgenroth, Kai M Udert
Ammonia oxidation decreases the pH in wastewaters where alkalinity is limited relative to total ammonia. The activity of ammonia oxidizing bacteria (AOB), however, typically decreases with pH and often ceases completely in slightly acidic wastewaters. Nevertheless, nitrification at low pH has been reported in reactors treating human urine, but it has been unclear which organisms are involved. In this study, we followed the population dynamics of ammonia oxidizing organisms and reactor performance in synthetic fully hydrolyzed urine as the pH decreased over time in response to a decrease in the loading rate...
June 5, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28500038/enrichment-and-physiological-characterization-of-a-cold-adapted-nitrite-oxidizer-nitrotoga-sp-from-eelgrass-sediments
#20
Kento Ishii, Hirotsugu Fujitani, Kentaro Soh, Tatsunori Nakagawa, Reiji Takahashi, Satoshi Tsuneda
Nitrite-oxidizing bacteria (NOB) are responsible for the second step of nitrification in natural and engineered ecosystems. The recently discovered genus Nitrotoga belongs to the Betaproteobacteria and has potentially high environmental importance. Although environmental clones affiliated with Nitrotoga are widely distributed, the limited number of cultivated Nitrotoga results in poor understanding of their ecophysiological features. In this study, we successfully enriched the non-marine cold-adapted Nitrotoga sp...
May 12, 2017: Applied and Environmental Microbiology
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