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Updated: Jul 11, 2026
08:05
Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
Simultaneous nitrification and denitrification by diverse Diaphorobacter sp
Anshuman A Khardenavis1, Atya Kapley, Hemant J Purohit
1Environmental Genomics Unit, National Environmental Engineering Research Institute (NEERI), Nehru Marg, Nagpur, 440 020, India.
Applied Microbiology and Biotechnology
|September 19, 2007
Summary
Eight new bacterial strains, identified as Diaphorobacter sp., efficiently remove wastewater contaminants. These microbes perform simultaneous nitrification and denitrification, offering potential for high-nitrogen wastewater treatment.
Area of Science:
- Environmental Microbiology
- Wastewater Treatment Technologies
- Bioremediation
Background:
- Wastewater often contains recalcitrant organic pollutants and high nitrogen loads.
- Microbial communities in activated biomass play a crucial role in wastewater purification.
- Diaphorobacter species are known for their metabolic versatility in degrading pollutants.
Purpose of the Study:
- To isolate and identify novel bacterial strains from dye- and nitro-substituted chemical-laden wastewater.
- To evaluate the capability of these isolates for simultaneous nitrification and denitrification (SND) under aerobic conditions.
- To assess their potential for treating high-nitrogen wastewaters.
Main Methods:
- Isolation of bacterial strains from activated sludge.
- Identification using 16S rDNA sequence analysis and phylogenetic tree construction.
- Assessing chemical oxygen demand (COD), ammonia, and nitrate removal efficiencies.
- Monitoring aerobic nitrite release.
Main Results:
- Eight bacterial isolates closely related to Diaphorobacter sp. were identified with 99-100% sequence similarity.
- Selected strains (HPC 805, 815, 821, 856) achieved high COD (85-93%) and ammonia removal (92-96%).
- These strains demonstrated complete nitrate removal and aerobic nitrite release, indicating partial nitrification and subsequent aerobic denitrification.
Conclusions:
- The identified Diaphorobacter strains possess significant capabilities for simultaneous nitrification and denitrification under aerobic conditions.
- These bacteria show high efficiency in removing organic matter and nitrogen compounds.
- The strains are promising candidates for developing advanced biological treatment systems for high-nitrogen wastewaters.
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