Related Experiment Video
Updated: Jun 14, 2025
07:59
Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors
Published on: December 6, 2018
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Achieving endogenous partial denitrification by cultivating denitrifying glycogen-accumulating organisms
Lianrong Zhao1, Ziwei Chen1, Xiaoling Zhang1,2,3
1School of Water and Environment, Chang'an University, Xi'an, People's Republic of China.
Environmental Technology
|September 5, 2024
Summary
Denitrifying glycogen-accumulating organisms (DGAOs) were successfully induced to provide nitrite for anammox processes. This study highlights DGAOs
Area of Science:
- Environmental microbiology
- Wastewater treatment
- Biotechnology
Background:
- Anaerobic ammonia oxidation (anammox) is efficient for nitrogen removal but limited by nitrite availability.
- Endogenous partial denitrification (EPD) is a promising method to supply nitrite for anammox.
- Denitrifying glycogen-accumulating organisms (DGAOs) are hypothesized to drive EPD.
Purpose of the Study:
- To enrich DGAOs in a sequencing batch reactor (SBR).
- To investigate the role of DGAOs in EPD for nitrite production.
- To analyze the microbial community structure during EPD.
Main Methods:
- Gradual enrichment of GAOs using phosphorus limitation and withdrawal.
- Induction of DGAOs by adding sodium nitrate.
- Monitoring nitrate-to-nitrite transformation ratio (NTR).
- Microbial community analysis using 16S rRNA gene sequencing.
Main Results:
- DGAOs were successfully enriched, contributing up to 96% of carbon source conversion and 95% of nitrate reduction.
- The maximum nitrate-to-nitrite transformation ratio (NTR) reached 80%.
- Ca. Compatibactors dominated the microbial community (31.12%), while PAOs were scarce (1.02%).
Conclusions:
- DGAOs play a crucial role in the EPD process for stable nitrite generation.
- This DGAO-driven EPD can effectively support anammox processes.
- Microbial insights reveal Ca. Compatibactors as key players in DGAO-mediated EPD.
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