Recruiting high-efficiency denitrifying consortia using Pseudomonas aeruginosa.
Jiajie Wu1, Xiaolong Wang1, Yue Fu1
1School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China.
Water Research
|February 21, 2025
Summary
This study created a high-efficiency denitrifying microbial consortium for wastewater treatment. The novel method uses Pseudomonas aeruginosa to enrich key bacteria, improving nitrogen removal and reducing chemical oxygen demand.
Area of Science:
- Environmental Microbiology
- Wastewater Treatment Engineering
- Microbial Ecology
Background:
- Efficient nitrogen removal in wastewater treatment relies on denitrifying microbial communities.
- Constructing specialized microbial consortia is crucial for optimizing wastewater treatment processes.
Purpose of the Study:
- To develop a high-efficiency denitrifying microbial consortium using an integrated enrichment and bioaugmentation strategy.
- To investigate the microbial community dynamics and assembly processes under varying hydraulic retention times (HRTs).
Main Methods:
- Integrated top-down evolutionary enrichment and bottom-up bioaugmentation to construct a Pseudomonas-recruited denitrifying consortium (PRDC).
- Utilized 16S rRNA gene sequencing to analyze microbial community composition and shifts.
- Evaluated denitrification rates and chemical oxygen demand (COD) consumption under different HRTs and carrier filling ratios.
Main Results:
- Enriched a PRDC with a high specific denitrification rate (109.49 ± 10.58 mg N/(g MLVSS·h)).
- Identified dominant denitrifying genera (Halomonas, Thauera) replacing the initial Pseudomonas inoculum.
- Observed a shift in community assembly from homogeneous selection to ecological drift and dispersal limitation under shortened HRT.
- Achieved a 1.65-fold enhancement in sludge denitrification and reduced COD consumption with PRDC carriers.
Conclusions:
- Pseudomonas aeruginosa can act as a trigger to facilitate the enrichment of high-efficiency denitrifying consortia.
- Shortened HRT promotes microbial community diversity and competition, enhancing overall denitrification efficiency.
- The developed PRDC offers a novel and effective approach for nitrogen removal in wastewater treatment.
