Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:1 to 14:1) for simultaneous C & N removal

TURBO N® is a circulating-bed biofilm reactor that provides stable operation and high N removal for a wide range of N and BOD loadings. This paper describes the influence of operating conditions on biofilm composition and population dynamics when the TURBO N® is operated to achieve tertiary nitrification, simultaneous carbon and ammonia oxidation and total nitrogen removal when coupled with a pre-denitrification fixed floating bed reactor. In situ specific nitrification rates and respiration tests showed that ammonium and nitrite oxidizers became less active in the biofilm once oxidation of influent BOD became important. Analyses of community structure with oligonucleotide probes targeted to the 16S rRNA showed the same general trends for nitrifiers, but also suggested shifts in the makeup of the ammonium and nitrite oxidizers that could not be detected with respirometry or specific nitrification rates.

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Temperature response of denitrification and anammox reveals the adaptation of microbial communities to in situ temperatures in permeable marine sediments that span 50° in latitude

Biogeosciences Discussions ◽

10.5194/bgd-10-14595-2013 ◽

2013 ◽

Vol 10 (9) ◽

pp. 14595-14626 ◽

Cited By ~ 3

Author(s):

A. Canion ◽

J. E. Kostka ◽

T. M. Gihring ◽

M. Huettel ◽

J. E. E. van Beusekom ◽

...

Keyword(s):

Microbial Communities ◽

Marine Sediments ◽

Metabolic Response ◽

Anammox Bacteria ◽

Advective Flow ◽

Permeable Sediments ◽

N Removal ◽

In Situ Conditions ◽

Wide Range

Abstract. Despite decades of research on the physiology and biochemistry of nitrate/nitrite-respiring microorganisms, little is known regarding their metabolic response to temperature, especially under in situ conditions. The temperature regulation of microbial communities that mediate anammox and denitrification was investigated in near shore permeable sediments at polar, temperate, and subtropical sites with annual mean temperatures ranging from −5 to 23 °C. Total N2 production rates were determined using the isotope pairing technique in intact core incubations under diffusive and simulated advection conditions and ranged from 2 to 359 μmol N m−2 d−1. For the majority of sites studied, N2 removal was 2 to 7 times more rapid under advective flow conditions. Anammox comprised 6 to 14% of total N2 production at temperate and polar sites and was not detected at the subtropical site. Potential rates of denitrification and anammox were determined in anaerobic slurries in a temperature gradient block incubator across a temperature range of −1 to 42 °C. The highest optimum temperature (Topt) for denitrification was 36 °C and was observed in subtropical sediments, while the lowest Topt of 21 °C was observed at the polar site. Seasonal variation in the Topt was observed at the temperate site with values of 26 and 34 °C in winter and summer, respectively. The Topt values for anammox were 9 and 26 °C at the polar and temperate sites, respectively. The results demonstrate adaptation of denitrifying communities to in situ temperatures in permeable marine sediments across a wide range of temperatures, whereas marine anammox bacteria may be predominately psychrophilic to psychrotolerant. To our knowledge, we provide the first rates of denitrification and anammox from permeable sediments of a polar permanently cold ecosystem. The adaptation of microbial communities to in situ temperatures suggests that the relationship between temperature and rates of N removal is highly dependent on community structure.

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Effect of Mid-Term Cropping System Adoption on Soil Chemical Properties at Changunarayan Municipality, Bhaktapur, Nepal

Current Research in Agricultural Sciences ◽

10.18488/journal.68.2021.82.80.89 ◽

2021 ◽

Vol 8 (2) ◽

pp. 80-89

Author(s):

Saroj Koirala ◽

Santosh Shrestha ◽

Prashanta Raut ◽

Bikram Pandey ◽

Arbindra Timilsina

Keyword(s):

Organic Matter ◽

Total Nitrogen ◽

Soil Ph ◽

Cropping Systems ◽

C:N Ratio ◽

Chemical Properties ◽

Soil Chemical Properties ◽

Future Research ◽

Available Phosphorus ◽

Wide Range

Soil chemical properties plays a crucial role in crop yield. In this study, we evaluated the chemical properties of soils under three different cropping systems practiced for more than five years in Changunarayan municipality of Bhaktapur district of Nepal. The cropping systems includes- (i) cultivation inside polyhouse (Treatment A: polyhouse), (ii) paddy-wheat rotation (Treatment B: P-W), and (iii) paddy-wheat-vegetable rotation (Treatment C: P-W-V). Thirty-nine composite samples (13 replicates from each site) were taken from the area based on variation in landforms. Soil pH, organic matter (%), total nitrogen (%), available phosphorus (mgkg-1), and available potassium (mgkg-1) were evaluated for each sample. The study revealed that the soil pH was acidic and ranges between 4.71 and 5.39, organic matter (1.6-2.39%), total nitrogen (0.091-0.13%), phosphorus (4.48-29.24mg kg-1) and potassium (88.04-109.52 mg kg-1). A significant lower mean pH (4.71), and higher mean organic matter (2.39%), total nitrogen (0.13%) and available phosphorus (29.24 mgkg-1) were observed in cultivation under polyhouse. Incorporation of vegetable in paddy-wheat system gave significant (p<0.05) higher accumulation of soil phosphorus and consistently raised other nutrient status. Moreover, cultivation under polyhouse raised C:N ratio (10.55) significantly than other system. This finding can be relevant to wide range of readers that focus on soil chemical properties and can be used in developing future research strategy and sustainable soil management system in the area.

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SUSTAINABLE NITROGEN REMOVAL USING APPROPRIATE TECHNOLOGIES

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2017.11 ◽

2017 ◽

Vol 4 (1) ◽

Author(s):

Krishnanand Maillacheruvu ◽

Derek Hartmann

Keyword(s):

Rate Constant ◽

Nitrogen Removal ◽

Removal Rate ◽

Low Cost ◽

C:N Ratio ◽

Treatment Plant ◽

Agricultural Runoff ◽

Point Sources ◽

Nitrogen And Phosphorus ◽

N Removal

Nitrogen and phosphorus are two major pollutants that lead to eutrophication, adversely impact ecosystems, and lead to degradation of water quality, which impacts human health and sustainability. Pollution from point sources like wastewater and industry discharge is easier to control than non-point source pollution due to agricultural runoff and related activities. The USEPA is considering more strict standards for nitrogen and phosphorus discharge from point sources. The objective of this study was to use an appropriate low-cost wastewater technology to demonstrate removal of nitrogen from wastewater discharge using rotating biological contactors (RBCs) using different C:N ratios. The first-order nitrogen removal rate constant was found to be about 3.88 day-1 in experimental reactor systems, using RBC media from a local wastewater treatment plant (Greater Peoria Sanitary District). Phase I experiments, at C:N ratio of 2:1, with nitrogen removal rates of 60% in a single flow-through system. Phase II experiments for the limited carbon availability condition showed that the removal rate constant reduced by 30% and N-removal efficiency dropped to around 48%. Modeling showed that even under these conditions, multiple bioreactors operated in series could help achieve design treatment goals. The system achieved stability within a week of operation. Economics and sustainability issues are analyzed to determine if the process developed in this research is scalable to pilot-and full-scale conditions.

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Where are we with biofilms now? Where are we going?

Water Science & Technology ◽

10.2166/wst.2007.235 ◽

2007 ◽

Vol 55 (8-9) ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

B.E. Rittmann

Keyword(s):

Mathematical Modelling ◽

Microbial Ecology ◽

Microbial Fuel Cells ◽

Emerging Contaminants ◽

Advanced Materials ◽

Anammox Bacteria ◽

N Removal ◽

Wide Range ◽

Biofilm Detachment ◽

Materials Research

The IWA's BiofilmVI conference presented a wide range of research on biofilm systems. Particularly popular themes were nitrogen removal, mathematical modelling and microbial ecology. Emerging themes included biofilms with membranes, pathogens in biofilms, biofouling and detachment. Within microbial ecology and mathematical modelling, emphasis was given to N-removal systems, particularly involving nitrifiers and Anammox bacteria. Both themes also recognised the importance of biofilm detachment. Although biofilms on membranes gained attention, little interest was exhibited towards linking biofilms with other advanced materials, such as ceramics, conductors, semi-conductors or nano-materials. Research presented at BiofilmVI marked major advances in improving water sustainability towards removing BOD and N, but did not address many emerging contaminants, such as oxidised contaminants and endocrine disruptors. Attention to energy sustainability, such as with bio-hydrogen or microbial fuel cells, was minimal. Thus, research reported at BiofilmVI was strong towards “improving the expected” with regard to BOD and N removal, but not yet focused on “exploiting the unexpected” to deal with emerging pollutants and bio-energy.

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A biosurfactant-producing yeast Rhodotorula sp.CC01 utilizing landfill leachate as nitrogen source and its broad degradation spectra of petroleum hydrocarbons

10.21203/rs.3.rs-1070958/v1 ◽

2021 ◽

Author(s):

Xiaoyun Lin ◽

Hanghai Zhou ◽

Feng Zeng ◽

Lijia Jiang ◽

Edidiong Okokon Atakpa ◽

...

Keyword(s):

Nitrogen Source ◽

Landfill Leachate ◽

Petroleum Hydrocarbons ◽

Sole Carbon Source ◽

Removal Rate ◽

Cost Effective ◽

Effective Strategy ◽

N Removal ◽

Wide Range ◽

Cultivation Process

Abstract In this study, a biosurfactant producing strain, Rhodotorula sp. CC01 was isolated using landfill leachate as nitrogen source, while olive oil was determined as the best sole carbon source for producing biosurfactants. The biosurfactant produced by Rhodotorula sp. CC01 was characterized as glycolipids with a critical micelle concentration of 70 mg/L, which showed stability over a wide range of pH (2–12), salinity (0–100%), and temperature (20–100°C). During the cultivation process, the surface tension decreased from 51.87 to 28.20 mN/m in 15 h, and the removal efficiency of NH4+-N reached 84.2% after 75 h cultivation with a maximum NH4+-N removal rate of 3.92 mg·L-1·h−1. In addition, Rhodotorula sp. CC01 has proven to be of great potential in remediating petroleum hydrocarbons, as revealed by chromogenic assays. The findings of this study prove a cost-effective strategy for the production of BS by yeast through the utilization of landfill leachate.

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Temperature response of denitrification and anammox reveals the adaptation of microbial communities to in situ temperatures in permeable marine sediments that span 50° in latitude

Biogeosciences ◽

10.5194/bg-11-309-2014 ◽

2014 ◽

Vol 11 (2) ◽

pp. 309-320 ◽

Cited By ~ 33

Author(s):

A. Canion ◽

J. E. Kostka ◽

T. M. Gihring ◽

M. Huettel ◽

J. E. E. van Beusekom ◽

...

Keyword(s):

Microbial Communities ◽

Marine Sediments ◽

Metabolic Response ◽

Temperature Response ◽

Anammox Bacteria ◽

Advective Flow ◽

N Removal ◽

In Situ Conditions ◽

Wide Range

Abstract. Despite decades of research on the physiology and biochemistry of nitrate/nitrite-respiring microorganisms, little is known regarding their metabolic response to temperature, especially under in situ conditions. The temperature regulation of microbial communities that mediate anammox and denitrification was investigated in near shore permeable sediments at polar, temperate, and subtropical sites with annual mean temperatures ranging from −5 to 23 °C. Total N2 production rates were determined using the isotope pairing technique in intact core incubations under diffusive and simulated advection conditions and ranged from 2 to 359 μmol N m−2 d−1. For the majority of sites studied, N2 removal was 2–7 times more rapid under simulated advective flow conditions. Anammox comprised 6–14% of total N2 production at temperate and polar sites and was not detected at the subtropical site. Potential rates of denitrification and anammox were determined in anaerobic slurries in a temperature gradient block incubator across a temperature range of −1 °C to 42 °C. The highest optimum temperature (Topt) for denitrification was 36 °C and was observed in subtropical sediments, while the lowest Topt of 21 °C was observed at the polar site. Seasonal variation in the Topt was observed at the temperate site with values of 26 and 34 °C in winter and summer, respectively. The Topt values for anammox were 9 and 26 °C at the polar and temperate sites, respectively. The results demonstrate adaptation of denitrifying communities to in situ temperatures in permeable marine sediments across a wide range of temperatures, whereas marine anammox bacteria may be predominately psychrophilic to psychrotolerant. The adaptation of microbial communities to in situ temperatures suggests that the relationship between temperature and rates of N removal is highly dependent on community structure.

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Simultaneous Partial Nitrification and Denitrification Maintained in Membrane Bioreactor for Nitrogen Removal and Hydrogen Autotrophic Denitrification for Further Treatment

Membranes ◽

10.3390/membranes11120911 ◽

2021 ◽

Vol 11 (12) ◽

pp. 911

Author(s):

Kun Dong ◽

Xinghui Feng ◽

Wubin Wang ◽

Yuchao Chen ◽

Wei Hu ◽

...

Keyword(s):

High Throughput Sequencing ◽

Dominant Role ◽

Domestic Sewage ◽

Biofilm Reactor ◽

Partial Nitrification ◽

Ammonia Oxidizing Bacteria ◽

Autotrophic Denitrification ◽

Membrane Biofilm Reactor ◽

N Removal ◽

Wide Range

Low C/N wastewater results from a wide range of factors that significantly harm the environment. They include insufficient carbon sources, low denitrification efficiency, and NH4+-N concentrations in low C/N wastewater that are too high to be treated. In this research, the membrane biofilm reactor and hydrogen-based membrane biofilm reactor (MBR-MBfR) were optimized and regulated under different operating parameters: the simulated domestic sewage with low C/N was domesticated and the domestic sewage was then denitrified. The results of the MBR-MBfR experiments indicated that a C/N ratio of two was suitable for NH4+-N, NO2−-N, NO3−-N, and chemical oxygen demand (COD) removal in partial nitrification-denitrification (PN-D) and hydrogen autotrophic denitrification for further treatment. The steady state for domestic wastewater was reached when the MBR-MBfR in the experimental conditions of HRT = 15 h, SRT = 20 d, 0.04 Mpa for H2 pressure in MBfR, 0.4–0.8 mg/L DO in MBR, MLSS = 2500 mg/L(MBR) and 2800 mg/L(MBfR), and effluent concentrations of NH4+-N, NO3−-N, and NO2−-N were 4.3 ± 0.5, 1.95 ± 0.04, and 2.05 ± 0.15 mg/L, respectively. High-throughput sequencing results revealed the following: (1) The genus Nitrosomonas as the ammonia oxidizing bacteria (AOB) and Denitratisoma as potential denitrifiers were simultaneously enriched in the MBR; (2) at the genus level, Meiothermus,Lentimicrobium, Thauera,Hydrogenophaga, and Desulfotomaculum played a dominant role in leading to NO3−-N and NO2−-N removal in the MBfR.

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Litter quality of native herbaceous legumes in a burned pine forest of the Georgia Piedmont

Canadian Journal of Forest Research ◽

10.1139/x92-263 ◽

1992 ◽

Vol 22 (12) ◽

pp. 2007-2010 ◽

Cited By ~ 19

Author(s):

Joseph J. Hendricks ◽

Lindsay R. Boring

Keyword(s):

C:N Ratio ◽

Leaf Tissue ◽

Pine Forest ◽

Senescent Leaf ◽

Substrate Quality ◽

Herbaceous Legumes ◽

Nitrogen Retranslocation ◽

Wide Range ◽

Georgia Piedmont

The objectives of this study were to compare the nitrogen retranslocation efficiency and the litter substrate quality of eight native and one naturalized herbaceous legume species growing in a periodically burned pine forest of the Georgia Piedmont. A survey of the nine species revealed a wide range of nitrogen retranslocation (8.3–51.9%) from senescent leaf tissue, as well as differences in nitrogen concentrations (0.9–2.5%), C:N ratios (17.7–51.2), and initial lignin contents (8.6–20.1%) of senescent leaves. Intraspecific differences in Desmodiumviridiflorum L., Lespedezahirta L., and Lespedezaprocumbens Michx. were found in the leaf, stem, coarse- and fine-root tissue C:N ratio and in the lignin concentrations. Overall, the litter of these nitrogen-fixing herbaceous legumes is predicted to decompose at moderate rates and may have a significant effect upon the long-term soil organic matter and soil nitrogen accumulations of frequently burned forest sites.

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Stochastic Turing patterns in a synthetic bacterial population

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1720770115 ◽

2018 ◽

Vol 115 (26) ◽

pp. 6572-6577 ◽

Cited By ~ 64

Author(s):

David Karig ◽

K. Michael Martini ◽

Ting Lu ◽

Nicholas A. DeLateur ◽

Nigel Goldenfeld ◽

...

Keyword(s):

Pattern Formation ◽

Bacterial Population ◽

Linear Instability ◽

Genetically Engineered ◽

Periodic Pattern ◽

Birth And Death Processes ◽

Alan Turing ◽

Wide Range ◽

Pattern Forming ◽

Activator Inhibitor

The origin of biological morphology and form is one of the deepest problems in science, underlying our understanding of development and the functioning of living systems. In 1952, Alan Turing showed that chemical morphogenesis could arise from a linear instability of a spatially uniform state, giving rise to periodic pattern formation in reaction–diffusion systems but only those with a rapidly diffusing inhibitor and a slowly diffusing activator. These conditions are disappointingly hard to achieve in nature, and the role of Turing instabilities in biological pattern formation has been called into question. Recently, the theory was extended to include noisy activator–inhibitor birth and death processes. Surprisingly, this stochastic Turing theory predicts the existence of patterns over a wide range of parameters, in particular with no severe requirement on the ratio of activator–inhibitor diffusion coefficients. To explore whether this mechanism is viable in practice, we have genetically engineered a synthetic bacterial population in which the signaling molecules form a stochastic activator–inhibitor system. The synthetic pattern-forming gene circuit destabilizes an initially homogenous lawn of genetically engineered bacteria, producing disordered patterns with tunable features on a spatial scale much larger than that of a single cell. Spatial correlations of the experimental patterns agree quantitatively with the signature predicted by theory. These results show that Turing-type pattern-forming mechanisms, if driven by stochasticity, can potentially underlie a broad range of biological patterns. These findings provide the groundwork for a unified picture of biological morphogenesis, arising from a combination of stochastic gene expression and dynamical instabilities.

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