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Updated: Jul 13, 2026
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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
[Nitrogen removal by Bacillus sp. LY with heterotrophic nitrification ability]
1School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China. hex@sjtu.edu.cn
Huan Jing Ke Xue= Huanjing Kexue
|August 7, 2007
Summary
Bacillus sp. LY efficiently removes nitrogen, converting organic nitrogen to ammonium and then to N2. Optimal removal occurs at moderate organic material concentrations, suggesting potential for new high-efficiency biological nitrogen removal processes.
Area of Science:
- Environmental microbiology
- Wastewater treatment technologies
Background:
- Nitrogen removal from wastewater is crucial for environmental protection.
- Biological nitrogen removal processes are essential for mitigating eutrophication.
Purpose of the Study:
- To investigate the nitrogen removal capabilities of Bacillus sp. LY.
- To elucidate the influence of ammonium and organic matter concentrations on nitrogen removal efficiency.
- To explore the metabolic pathways involved in nitrogen transformation by Bacillus sp. LY.
Main Methods:
- Culturing Bacillus sp. LY under varying ammonium-nitrogen loads (40, 80, 120 mg/L).
- Assessing nitrogen removal rates at different organic material concentrations.
- Analyzing the transformation pathways of organic nitrogen to ammonium and subsequently to N2.
Main Results:
- Bacillus sp. LY achieved 100% ammonium-nitrogen removal at 40 mg/L load.
- Nitrogen removal efficiency decreased with increasing ammonium concentration.
- Moderate organic material concentration optimized nitrogen removal, while low and high concentrations were inhibitory or non-enhancing.
- Identified two potential pathways for nitrogen transformation: nitrification-denitrification and direct ammonium oxidation to N2 via hydroxylamine and N2O.
Conclusions:
- Bacillus sp. LY demonstrates significant potential for biological nitrogen removal.
- Optimizing organic matter concentration is key for maximizing nitrogen removal efficiency.
- The identified metabolic pathways offer insights for developing novel, high-efficiency nitrogen removal strategies.
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