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Frontiers of Environmental Science & Engineering 2021年第5期15卷 247-256页

作者： Yi Qian Weichuan Qiao Yunhao Zhang Department of Environmental Engineering College of Biology and the EnvironmentNanjing Forestry UniversityNanjing210037China

The toxicities of sodium perfluorononyloxy-benzenesulfonate(OBS)to animals and plants are similar to those of perfluorooctane sulfonate.However,the mechanism of its toxicity to aerobic denitrifying bacteria is still unclear.In the present study,the ecotoxicity of OBS on an aerobic denitrifying strain,Pseudomonas stutzeri,was evaluated.The results showed that a dosage of OBS clearly affected the growth and Aerobic denitrification of P.stutzeri.When compared with an unamended control,the degradation efficiency of the total nitrogen decreased by 30.13%during exposure to 200 mg/L of OBS,and the complete degradation time of nitrate-nitrogen was delayed by 4 h.The lactate dehydrogenase and superoxide dismutase produced by the bacteria increased with the concentration of OBS,and reactive oxygen species were also detected by confocal laser scanning microscope imaging.Transmission electron microscope imaging revealed chromosome deformation of the cells and damage to cell content;moreover,outer membrane vesicles were secreted from the bacteria,which was the important detoxification mechanism of P.stutzeri to OBS.Expression of the genes involved in aerobic nitrification and oxidative stress were also changed under OBS stress,which further confirmed the toxicity of OBS to P stutzeri.This study reveals the environmental exposure risk of OBS from the perspective of microorganisms.

关键词： Sodium perfluorononyloxy-benzenesulfonate Aerobic denitrification Pseudomonas stutzeri Ecotoxicity ROS

Temperature effect on Aerobic denitrification and nitrification

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Journal of Environmental Sciences 2003年第5期15卷 669-673页

作者： XIE Shu guang ZHANG Xiao jian WANG Zhan sheng Department of Environmental Science and Technology Tsinghua UniversityBeijing 100084China.

Nitrogen loss without organic removal in biofilter was observed and its possible reason was explained. A lower hydraulic loading could improve Aerobic denitrification rate. Aerobic denitrification was seriously affected by low temperature(below 10℃). However, nitrification rate remained high when the temperature dropped from 15℃ to 5℃. It seemed the autotrophic biofilm in BAF could alleviate the adverse effect of low temperature.

关键词： Aerobic denitrification nitrification biofilter temperature effect

denitrification characteristics of a marine origin psychrophilic aerobic denitrifying bacterium

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Journal of Environmental Sciences 2011年第11期23卷 1888-1893页

作者： Haiyan Zheng Ying Liu Guangdong Sun Xiyan Gao Qingling Zhang Zhipei Liu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China.

A psychrophilic aerobic denitrifying bacterium,strain S1-1,was isolated from a biological aerated filter conducted for treatment of recirculating water in a marine aquaculture system.Strain S1-1 was preliminarily identified as Psychrobacter sp.based on the analysis of its 16S rRNA gene sequence,which showed 100% sequence similarity to that of Psychrobacter sp.TSBY-70.Strain S1-1 grew well either in high nitrate or high nitrite conditions with a removal of 100% nitrate or 63.50% nitrite,and the total nitrogen removal rates could reach to 46.48% and 31.89%,respectively.The results indicated that nitrate was mainly reduced in its logarithmic growth phase with a very low leve1 accumulation of nitrite,suggesting that the Aerobic denitrification process of strain S1-1 occurred mainly in this phase.The GC-MS results showed that N 2 O was formed as the major intermediate during the aerobic denitrifying process of strain S1-1.Finally,factors affecting the growth of strain S1-1 and its aerobic denitrifying ability were also investigated.Results showed that the optimum Aerobic denitrification conditions for strain S1-1 were sodium succinate as carbon source,C/N ratio15,salinity 10 g/L NaCl,incubation temperature 20°C and initial pH 6.5.

关键词： nitrogen removal Aerobic denitrification marine environment low temperature Psychrobacter sp.S1-1

Bioaugmentation of two-stage aerobic sequencing batch reactor with mixed strains for high nitrate nitrogen wastewater treatment

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3103-3109页

作者： Mengmeng Wang Gang Cao Naixian Feng Yongzhang Pan College of Environment Jinan UniversityGuangzhou 511443China Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials College of Life Science and TechnologyJinan UniversityGuangzhou 510632China

Mixed strains Delftia sp.YH01 and Acidovorax sp.YH02,with capability of heterotrophic nitrification-Aerobic denitrification,were introduced into a two-stage aerobic sequencing batch reactor to enhance NO3^--N removal.With optimal C/N of 8,efficient NO3^--N removal was achieved at initial NO3^--N concentration of 2000 mg·L−1.Meanwhile,the massive accumulation of NO2^--N was avoided during the long operation.Compared to the one-stage aerobic sequencing batch reactor,the removal efficiency of NO3^--N and TN in the two-stage aerobic sequencing batch reactor was increased by 36.5% and 42.7%,which respectively was 93.8% and 88.4%.Microbial community study showed that the mixed strains have the stronger viability and can synergistically denitrify with the indigenous microorganisms in system,such as Azoarcus,Uncultured Saprospiraceae,Thauera,Paracocccus,which could be major contributors for Aerobic denitrification.The proposed technology was shown to achieve high-efficiency treatment of high NO3^--N wastewater through Aerobic denitrification.

关键词： Waste water Biological engineering Bioreactors Aerobic denitrification Bioaugmentation Microbial community

Sustainable treatment of nitrate-containing wastewater by an autotrophic hydrogen-oxidizing bacterium

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Environmental Science and Ecotechnology 2022年第1期9卷 53-59页

作者： Yi-Zhen Chen Li-Juan Zhang Ling-Yun Ding Yao-Yu Zhang Xi-Song Wang Xue-Jiao Qiao Bao-Zhu Pan Zhi-Wu Wang Nan Xu Hu-Chun Tao Key Laboratory for Heavy Metal Pollution Control and Reutilization School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen518055GuangdongChina College of Health Science and Environmental Engineering Shenzhen Technology UniversityShenzhen518118GuangdongChina State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China Xi'an University of TechnologyXi'an710048ShaanxiChina Department of Civil and Environmental Engineering Virginia Polytechnic Institute and State UniversityManassas20147VirginiaUSA

Bacteria are key denitrifiers in the reduction of nitrate(NO_(3)^(-)N),which is a contaminant in wastewater treatment plants(WWTPs).They can also produce carbon dioxide(CO_(2))and nitrous oxide(N2O).In this study,the autotrophic hydrogen-oxidizing bacterium Rhodoblastus sp.TH_(2)0 was isolated for sustainable treatment of NO_(3)^(-)N in wastewater.Efficient removal of NO_(3)^(-)N and recovery of biomass nitrogen were achieved.Up to 99%of NO_(3)^(-)N was removed without accumulation of nitrite and N2O,consuming CO_(2)of 3.25 mol for each mole of NO_(3)^(-)N removed.The overall removal rate of NO_(3)^(-)N reached 1.1 mg L^(-1)h^(-1)with a biomass content of approximately 0.71 g L^(-1)within 72 h.TH20 participated in NO_(3)^(-)N assimilation and Aerobic denitrification.Results from 15N-labeled-nitrate test indicated that removed NO_(3)^(-)N was assimilated into organic nitrogen,showing an assimilation efficiency of 58%.Seventeen amino acids were detected,accounting for 43%of the biomass.Nitrogen loss through Aerobic denitrification was only approximately 42%of total nitrogen.This study suggests that TH_(2)0 can be applied in WWTP facilities for water purification and production of valuable biomass to mitigate CO_(2)and N_(2)O emissions。

关键词： Wastewater Nitrate Hydrogen-oxidizing bacteria Autotrophic assimilation Aerobic denitrification

Heterotrophic ammonium removal characteristics of an aerobic heterotrophic nitrifying-denitrifying bacterium, Providencia rettgeri YL

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Journal of Environmental Sciences 2009年第10期21卷 1336-1341页

作者： TAYLOR Shauna M School of Environmental Science and Engineering Shanghai Jiao Tong University

Bacterium Providencia rettgeri YL was found to exhibit an unusual ability to heterotrophically nitrify and aerobically denitrify various concentrations of ammonium （NH4^＋-N）. In order to further understand its removal ability, several experiments were conducted to identify the growth and ammonium removal response at different carbon to nitrogen （C/N） mass ratios, shaking speeds, temperatures, ammonium concentrations and to qualitatively verify the production of nitrogen gas using gas chromatography techniques. Results showed that under optimum conditions （C/N 10, 30℃, 120 r/min）, YL can significantly remove low and high concentrations of ammonium within 12 to 48 h of growth, respectively. The nitrification products hydroxylamine （NHzOH）, nitrite （NO2^-） and nitrate （NO3^-） as well as the denitrification product, nitrogen gas （N2）, were detected under completely aerobic conditions.

关键词： Providencia rettgeri YL heterotrophic ammonium removal Aerobic denitrification

Isolation and Characterization of a New Heterotrophic Nitrifying Bacillus sp. Strain

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Biomedical and Environmental Sciences 2007年第6期20卷 450-455页

作者： YAN LIN HAI-NAN KONG YI-LIANG HE BIN-BIN LIU YUHIE INAMORI LI YAN School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China Department of Biotechnology Shanghai Jiaotong University Shanghai 200240 China National Institute for Environmental Studies 16-2 Onogawa Tsukuba 305-8506 Ibaraki Japan

Objective To characterize the heterotrophic nitrifying bacteria. Methods The bacteria were isolated from membrane bioreactor for treating synthetic wastewater using the method newly introduced in this study. Fluorescence in situ hybridization （FISH） was used to validate the nonexistence of autotrophic ammonia oxidizers and nitrite oxidizers. Batch tests were carried out to investigate the capability of heterotrophic nitrification by the pure culture. Phylogenetic analysis of the pure culture was performed. Results A heterotrophic nitrifier, named Bacillus sp. LY, was newly isolated from the membrane bioreactor system in which the efficiency of TN removal was up to 80%. After 24-day, incubation, the removal efficiency of COD by Bacillus sp. LY was 71.7 %. The ammonium nitrogen removal rate after assimilation nearly ceased by Bacillus sp. LY was 74.7% The phylogenetic tree of Bacillus sp. LY and the neighbouring nitrifiers were given. Conclusions The batch test results indicate that Bacillus sp. LY can utilize the organic carbon as the source of assimilation when it grows on glucose and ammonium chloride medium accompanying the formation of oxidized-nitrogen. It also can denitrify nitrate while nitrifying. Bacillus sp. LY may become a new bacterial resource for heterotrophic nitrification and play a bioremediation role in nutrient removal.

关键词： 16S rDNA Aerobic denitrification Bacillus Heterotrophic nitrification Phylogenetic analysis

Isolation and characterization of heterotrophic nitrifying bacteria in MBR

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Journal of Environmental Sciences 2005年第4期17卷 589-592页

作者： LINYan HEYi-liang KONGHai-nan LIUBin-bin LIYan INAMONYuhei SchoolofEnvironmentalScienceandEngineering ShanghaiJiaotongUniversityShanghai200240China. DepartmentofBiotechnology ShanghaiJiaotongUniversityShanghai200240China NationalInstituteforEnvironmentalStudies16-20nogawa.Tsukuba IbarakiJapan）

The study presented the method for isolating the heterotrophic nitrifiers and the characterization of heterotrophic nitrification. Continuous tests via a membrane bioreactor (MBR) were operated under the controlled conditions to proliferate the nitrifiers. Heterotrophic nitrifying bacteria were isolated from the system in which the efficiency of total nitrogen(TN) removal was up to 80%. Since no autotrophic ammonium and nitrite oxidizers could be detected by fluorescence in situ hybridization(FISH), oxidized-N production was unlikely to be catalyzed by autotrophic nitrifiers during the heterotrophic nitrifiers' isolation in this study. The batch test results indicate that the isolated heterotrophic bacteria were able to nitrify. After 3 weeks incubation, the efficiencies of the COD removal by the three isolated bacterial strains B1, B2, and B3 were 52 6%, 71 7%, and 77 7%, respectively. The efficiencies of the TN removal by B1, B2, and B3 were 35 6%, 61 2% and 68 7%, respectively.

关键词： membrane bioreactor(MBR) simultaneous nitrification and denitrification(SND) heterotrophic nitrification Aerobic denitrification

High nitrogen removal from wastewater with several new aerobic bacteria isolated from diverse ecosystems

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Journal of Environmental Sciences 2006年第3期18卷 525-529页

作者： NAHIMANA Liberat College of Life Sciences Central China Normal University Wuhan 430079 China

Three new bacteria HS-03, HS-043 and HS-047 isolated from different ecosystems were found capable of Aerobic denitrification. The potential application of these strains in wastewater treatment under aerobic conditions was investigated, These three bacteria all presented high nitrogen removal from wastewater that more than 98% of 10 mmol/L nitrate could be removed in 12--24 h by adding cheap external carbon source and low concentration of iron as well as molybdate. The mechanism at molecular level was analyzed. The success of this Aerobic denitrification applied to wastewater treatment may serve as an alternative to enhance the practical nitrogen removal from wastewater. Main biochemical and physiological features of these strains were characterized. The 16S rDNA sequences were compared with the published data in GenBank by using BLAST. The results of phenotype and genotype proved that strain HS-03 and HS-047 belonged to Pseudomonas stutzeri and Pseudomonas pseudoalcaligenes respectively. Strain HS-043 was identified as Delftia clcidovorans of which denitrifying activity has not previously been explored.

关键词： high nitrogen removal Aerobic denitrification wastewater treatment identification

Screening and Characterization of Nitrite-Degrading Bacterial Isolates Using a Novel Culture Medium

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Journal of Ocean University of China 2020年第1期19卷 241-248页

作者： MA Qingshan HE Zengguo School of Medicine and Pharmacy Ocean University of ChinaQingdao 266003China Marine Biomedical Research Institute of Qingdao Qingdao 266003China

In this study,a novel culture medium that simulates shrimp pond conditions was established to screen nitrite-degrading isolates.The medium was supplemented with nitrite as a nitrogen source and shrimp feed as the major carbon source,to achieve the high nitrogen and low carbon nutritional status found in shrimp farming ponds.Screening using this medium identified potent denitrifying Bacillus isolates,among which Bacillus subtilis M7-1 was considered best.M7-1 was able to completely degrade nitrite-N in 24 h without much consumption of dissolved oxygen.Efficient denitrification activity took place in liquid cultures within a set of non-stringent ranges of pH(5.0–9.0),salinity(0–30)and temperature(25–35℃).The denitrifying enzyme gene was amplified,sequenced and further identified as nirS type.In biosecurity assessments,M7-1 had no negative effects on shrimps at a dose of 106 cfu mL−1.M7-1 could therefore be used in aquaculture to reduce and control the nitrogen concentration,and to promote the development of sustainable and healthy culture systems.

关键词： Aerobic denitrification nitrite screening culture medium Bacillus subtilis