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Ammonia oxidizing bacteria

Guangming Zeng, Lihua Zhang, Haoran Dong, Yaoning Chen, Jiachao Zhang, Yuan Zhu, Yujie Yuan, Yankai Xie, Wei Fang
Polyvinylpyrrolidone coated silver nanoparticles (PVP-AgNPs) were applied at different concentrations to reduce total nitrogen (TN) losses and the mechanisms of nitrogen bio-transformation were investigated in terms of the nitrogen functional enzymes and genes. Results showed that mineral N in pile 3 which was treated with AgNPs at a concentration of 10 mg/kg compost was the highest (6.58 g/kg dry weight (DW) compost) and the TN loss (47.07%) was the lowest at the end of composting. Correlation analysis indicated that TN loss was significantly correlated with amoA abundance...
December 29, 2017: Bioresource Technology
Papitchaya Srithep, Preeyaporn Pornkulwat, Tawan Limpiyakorn
In this study, two laboratory nitrifying reactors (NRI and NRII), which were seeded by sludge from different sources and operated under different operating conditions, were found to possess distinct dominant ammonia-oxidizing microorganisms. Ammonia-oxidizing archaeal (AOA) amoA genes outnumbered ammonia-oxidizing bacterial (AOB) amoA genes in reactor NRI, while only AOB amoA genes were detectable in reactor NRII. The AOA amoA gene sequences retrieved from NRI were characterized within the Nitrososphaera sister cluster of the group 1...
January 10, 2018: Environmental Science and Pollution Research International
Yu Zhang, Rui Sun, Aijuan Zhou, Jiaguang Zhang, Yunbo Luan, Jianna Jia, Xiuping Yue, Jie Zhang
Most studies have employed aeration-biofiltration process for the simultaneous removal of iron, manganese and ammonia in groundwater. However, what's inside the "black box", i.e., the potential contribution of functional microorganisms behavior and interactions have seldom been investigated. Moreover, little attention has been paid to the correlations between environmental variables and functional microorganisms. In this study, the performance of industrial-scale biofilters for the contaminated groundwater treatment was studied...
January 8, 2018: AMB Express
Yukihiro Tashiro, Kosuke Kanda, Yuya Asakura, Toshihiko Kii, Huijun Cheng, Pramod Poudel, Yuki Okugawa, Kosuke Tashiro, Kenji Sakai
A unique autothermal thermophilic aerobic digestion (ATAD) process has been used to convert human excreta to liquid fertilizer in Japan. This study investigated the physicochemical and bacterial community characteristic changes during the full-scale ATAD process operated for approximately 3 weeks in 2 different years. After initiating simultaneous aeration and mixing using an air-inducing circulator (aerator), the temperature autothermally increased rapidly in the first 1-2 d with exhaustive oxygen consumption, leading to a drastic decrease and gradual increase in oxidation-reduction potential in the first 2 d, which reached > 50°C in the middle 4-6 d and remained steady in the final phase...
January 5, 2018: Applied and Environmental Microbiology
Bo-Min Ki, In Ae Huh, Jung-Hyun Choi, Kyung-Suk Cho
The relationships between nutrient dynamics and the bacterial community at the water-sediment interface were investigated using the results of nutrient release fluxes, bacterial communities examined by 16S rRNA pyrosequencing and canonical correlation analysis (CCA) accompanied by lab-scale benthic chamber experiment. The nutrient release fluxes from the sediments into the water were as follows: -3.832 to 12.157 mg m-2 d-1 for total phosphorus, 0.049 to 9.993 mg m-2 d-1 for PO4-P, -2.011 to 41.699 mg m-2 d-1 for total nitrogen, -7...
January 5, 2018: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
Hongyan Zhang, Jie Lv, Zhenhong Jia
We successfully demonstrate a porous silicon (PS) double Bragg mirror by electrochemical etching at room temperature as a deoxyribonucleic acid (DNA) label-free biosensor for detecting ammonia-oxidizing bacteria (AOB). Compared to various other one-dimension photonic crystal configurations of PS, the double Bragg mirror structure is quite easy to prepare and exhibits interesting optical properties. The width of high reflectivity stop band of the PS double Bragg mirror is about 761 nm with a sharp and deep resonance peak at 1328 nm in the reflectance spectrum, which gives a high sensitivity and distinguishability for sensing performance...
January 1, 2018: Sensors
Jiao Chen, Yixin Lu, Jun Cheng, Jianqiang Zhang
Three constructed rapid infiltration (CRI) systems (C1, C2 and C3) were operated under 7, 14 and 21 days of continuous starvation, respectively. The effect of starvation on the ammonia removal efficiency (ARE), nitrite accumulation rate (NAR), bioactivity of nitrifiers and content of extracellular polymeric substances (EPS) was investigated. The results showed that the activity of nitrite-oxidizing bacteria (NOB) was higher than that of ammonia-oxidizing bacteria (AOB) in stabilization periods, leading to a complete nitrification in CRI systems...
January 4, 2018: Environmental Technology
Lindsey K Deignan, Joseph R Pawlik, Patrick M Erwin
The brown tube sponge Agelas tubulata (cf. Agelas conifera) is an abundant and long-lived sponge on Caribbean reefs. Recently, a disease-like condition, Agelas wasting syndrome (AWS), was described from A. tubulata in the Florida Keys, where prevalence of the syndrome increased from 7 to 35% of the sponge population between 2010 and 2015. In this study, we characterized the prokaryotic symbiont community of A. tubulata for the first time from individuals collected within the same monitoring plots where AWS was described...
January 3, 2018: Microbial Ecology
Daisuke Hira, Nobuyuki Aiko, Yoshinori Yabuki, Takao Fujii
Nitrogenous pollution of water is regarded as a global environmental problem, and nitrogen removal has become an important issue in wastewater treatment processes. Landfill leachate is a typical large source of nitrogenous wastewater. Although the characteristics of leachate vary according to the age of the landfill, leachates of mature landfill have high concentrations of nitrogenous compounds. Most nitrogen in these leachates is in the form of ammonium nitrogen. In this study, we investigated the bacterial community of sludge from a landfill leachate lagoon by pyrosequencing of the bacterial 16S rRNA gene...
December 29, 2017: Journal of Environmental Management
Maoxia Chen, Yangwu Chen, Shiyang Dong, Shuhuan Lan, Houzhen Zhou, Zhouliang Tan, Xudong Li
In this study, the nitrification performance, metabolic activity, antioxidant enzyme activity as well as bacterial community of mixed nitrifying bacteria culture under different temperature dropping strategies [(#1) growth temperature kept at 20 °C; (#2) sharp1 decreased from 20 °C to 10 °C; (#3) growth at 20 °C for 6 days followed by sharp decrease to 10 °C; and (#4) gradual decreased from 20 °C to 10 °C] were evaluated. It was shown that acclimation at 20 °C for 6 days allowed to maintain better nitrification activity at 10 °C...
December 28, 2017: Chemosphere
Huanhuan Wang, Xu Li, Xiang Li, Xinyu Li, Jian Wang, Huiwen Zhang
Microbial communities play critical roles in soil nitrogen (N) cycle; however, we have limited understanding of the distribution of N-cycling microbial groups in deeper soil horizons. In this study, we used quantitative PCR to characterize the changes of microbial populations (16S rRNA and 18S rRNA) and five key N-cycling gene abundances involved in N fixation (nifH), ammonia oxidation (amoA) by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA), and nitrite reduction (nirS and nirK) along profiles (0-100 cm depth) of different paddy soils from three regions (Hailun, Changshu, Yingtan) across China from north to south...
2017: PloS One
Bryce A Figdore, H David Stensel, Mari-Karoliina H Winkler
Three types of nitrifying granules were grown on media simulating anaerobic digestion dewatering reject water and compared for their potential to increase nitrification capacity when added to mainstream flocculent activated sludge treatment. An advantage of nitrification bioaugmentation with sidestream granules instead of flocculent biomass is that the granules can be selectively maintained at longer retention times than flocs and thus provide higher nitrification capacity from bioaugmentation. The three granule types and feeding conditions were: nitrifying granules with aerobic feeding, nitrifying-denitrifying granules with anoxic feeding, and nitrifying-denitrifying/phosphate-accumulating (NDN-PAO) granules with anaerobic feeding...
November 6, 2017: Bioresource Technology
Jinhua Wang, Lanjun Wang, Lusheng Zhu, Jun Wang
The negative effects of residues from antibiotics and heavy metals in agricultural soils are becoming an increasingly frequent concern. To evaluate the toxicity and interaction of antibiotics and heavy metals, enrofloxacin (ENR) and cadmium (Cd) were used as targets to study the individual effects of ENR (0.025, 0.1, 0.4mmol/kg) and Cd (0.4mmol/kg) and their combined effects (mole ratios of ENR to Cd of 1: 1, 1: 4 and 1: 16) on soil microbial biomass and function on days 7, 14, 21 and 28 of the study. The results demonstrated that microbial populations, which were counted during 4 sampling periods, were mainly in the order of bacteria>actinomycetes>fungi...
December 20, 2017: Science of the Total Environment
Clara A Fuchsman, Allan H Devol, Jaclyn K Saunders, Cedar McKay, Gabrielle Rocap
Microbial communities in marine oxygen deficient zones (ODZs) are responsible for up to half of marine N loss through conversion of nutrients to N2O and N2. This N loss is accomplished by a consortium of diverse microbes, many of which remain uncultured. Here, we characterize genes for all steps in the anoxic N cycle in metagenomes from the water column and >30 μm particles from the Eastern Tropical North Pacific (ETNP) ODZ. We use an approach that allows for both phylogenetic identification and semi-quantitative assessment of gene abundances from individual organisms, and place these results in context of chemical measurements and rate data from the same location...
2017: Frontiers in Microbiology
Shanghua Wu, Guoqiang Zhuang, Zhihui Bai, Yu Cen, Shengjun Xu, Haishu Sun, Xingguo Han, Xuliang Zhuang
Nitrous oxide (N2 O) is a long-lived greenhouse gas that can result in the alteration of atmospheric chemistry and cause accompanying changes in global climate. To date, many techniques have been used to mitigate the emissions of N2 O from agricultural fields, which represent one of the most important sources of N2 O. In this study, we designed a greenhouse pot experiment and a microcosmic serum bottle incubation experiment using acidic soil from a vegetable farm to study the effects of Bacillus amyloliquefaciens (BA) on plant growth and N2 O emission rates...
December 18, 2017: Global Change Biology
M El-Fadel, F Sleem, J Hashisho, P E Saikaly, I Alameddine, S Ghanimeh
This study examines the performance and fouling potential of flat sheet (FS) and hollow fiber (HF) membrane bioreactors (MBRs) during the treatment of high strength landfill leachate under varying solid retention times (SRT = 5-20 days). Mixed-liquor bacterial communities were examined over time using 16S rRNA gene sequence analysis in an attempt to define linkages between the system performance and the microbial community composition. Similarly, biofilm samples were collected at the end of each SRT to characterize the microbial communities that evolved on the surface of the FS and HF membranes...
December 14, 2017: Waste Management
Yu Su, Weidong Wang, Di Wu, Wei Huang, Mengzi Wang, Guibing Zhu
An integrated approach to document high ammonium oxidation rate in Guanjinggang constructed wetland (GJG-CW) was performed and the results showed that the substantial ammonium oxidation rate could be obtained by enhancing Ammonia Oxidizing Bacteria (AOB) activity rather than Ammonia Oxidizing Archaea (AOA) activity. In the plant-bed/ditch system, ditch center and plant-bed fringe were two active zones for NH4+-N removal with ammonium oxidation rate peaking at 2.98±0.04 and 2.15±0.02mgNkg-1d-1, respectively...
December 14, 2017: Science of the Total Environment
Maria Westerholm, Bettina Müller, Abhijeet Singh, Oskar Karlsson Lindsjö, Anna Schnürer
To enrich syntrophic acetate-oxidizing bacteria (SAOB), duplicate chemostats were inoculated with sludge from syntrophic acetate oxidation (SAO)-dominated systems and continuously supplied with acetate (0.4 or 7.5 g l-1 ) at high-ammonia levels. The chemostats were operated under mesophilic (37°C) or thermophilic (52°C) temperature for about six hydraulic retention times (HRT 28 days) and were sampled over time. Irrespective of temperature, a methane content of 64-69% and effluent acetate level of 0.4-1...
December 14, 2017: Microbial Biotechnology
Weixing Mi, Jianqiang Zhao, Xiaoqian Ding, Guanghuan Ge, Rixiang Zhao
To investigate the characteristics of anaerobic ammonia oxidation for treating low-ammonium wastewater, a continuous-flow completely autotrophic nitrogen removal over nitrite (CANON) biofilm reactor was studied. At a temperature of 32 ± 1 °C and a pH between 7.5 and 8.2, two operational experiments were performed: the first one fixed the hydraulic retention time (HRT) at 10 h and gradually reduced the influent ammonium concentrations from 210 to 50 mg L-1; the second one fixed the influent ammonium concentration at 30 mg L-1 and gradually decreased the HRT from 10 to 3 h...
December 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
V F Velho, B S Magnus, G C Daudt, J A Xavier, L B Guimarães, R H R Costa
N2O-production was investigated during nitrogen removal using aerobic granular sludge (AGS) technology. A pilot sequencing batch reactor (SBR) with AGS achieved an effluent in accordance with national discharge limits, although presented a nitrite accumulation rate of 95.79% with no simultaneous nitrification-denitrification. N2O production was 2.06 mg L-1 during the anoxic phase, with N2O emission during air pulses and the aeration phase of 1.6% of the nitrogen loading rate. Batch tests with AGS from the pilot reactor verified that at the greatest COD/N ratio (1...
December 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
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