Decryption for nitrogen removal in Anammox-based coupled systems: Nitrite-induced mechanisms

Yitong Liang; Zemin Li; Bin Zhang; Yushen Zhang; Sijia Ji; Guanglei Qiu; Haizhen Wu; Chaohai Wei

doi:10.1016/j.biortech.2023.129274

Decryption for nitrogen removal in Anammox-based coupled systems: Nitrite-induced mechanisms

Bioresour Technol. 2023 Sep:384:129274. doi: 10.1016/j.biortech.2023.129274. Epub 2023 Jun 7.

Authors

Yitong Liang¹, Zemin Li¹, Bin Zhang², Yushen Zhang¹, Sijia Ji¹, Guanglei Qiu³, Haizhen Wu², Chaohai Wei⁴

Affiliations

¹ School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China.
² School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, PR China.
³ School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou 510006, PR China.
⁴ School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou 510006, PR China. Electronic address: cechwei@scut.edu.cn.

PMID: 37290714
DOI: 10.1016/j.biortech.2023.129274

Abstract

This study investigated the effects of NO₂^- on synergetic interactions between Anammox bacteria (AnAOB) and sulfur-oxidizing bacteria (SOB) in an autotrophic denitrification-Anammox system. The presence of NO₂^- (0-75 mg-N/L) was shown to significantly enhance NH₄⁺ and NO₃^- conversion rates, achieving intensified synergy between AnAOB and SOB. However, once NO₂^- exceed a threshold concentration (100 mg-N/L), both NH₄⁺ and NO₃^- conversion rates decreased with increased NO₂^- consumption via autotrophic denitrification. The cooperation between AnAOB and SOB was decoupled due to the NO₂^- inhibition. Improved system reliability and nitrogen removal performance was achieved in a long-term reactor operation with NO₂^- in the influent; reverse transcription-quantitative polymerase chain reaction analysis showed elevated hydrazine synthase gene transcription levels (5.00-fold), comparing to these in the reactor without NO₂^-. This study elucidated the mechanism of NO₂^- induced synergetic interactions between AnAOB and SOB, providing theoretical guidance for engineering applications of Anammox-based coupled systems.

Keywords: Anammox; Autotrophic denitrification; Nitrite-induced; Nitrogen removal.

MeSH terms

Anaerobic Ammonia Oxidation
Bacteria
Bioreactors / microbiology
Denitrification*
Nitrites*
Nitrogen / analysis
Nitrogen Dioxide / analysis
Oxidation-Reduction
Reproducibility of Results
Sewage / microbiology
Sulfur

Substances

Nitrites
Nitrogen
Nitrogen Dioxide
Sulfur
Sewage