Revealing mechanisms of triclosan on the removal and distribution of nitrogen and phosphorus in microalgal-bacterial symbiosis system

Sheng-Long Chen; Tian-Yang Wang; Cong-Cong Tang; Rong Wang; Zhang-Wei He; Zhi-Hua Li; Yu Tian; Xiaochang C Wang

doi:10.1016/j.envpol.2023.122539

Revealing mechanisms of triclosan on the removal and distribution of nitrogen and phosphorus in microalgal-bacterial symbiosis system

Environ Pollut. 2023 Nov 15:337:122539. doi: 10.1016/j.envpol.2023.122539. Epub 2023 Sep 10.

Authors

Sheng-Long Chen¹, Tian-Yang Wang¹, Cong-Cong Tang², Rong Wang¹, Zhang-Wei He¹, Zhi-Hua Li¹, Yu Tian³, Xiaochang C Wang⁴

Affiliations

¹ Shaanxi Key Laboratory of Environmental Engineering, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
² Shaanxi Key Laboratory of Environmental Engineering, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an, 710055, China. Electronic address: cctang0820@xauat.edu.cn.
³ State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
⁴ Shaanxi Key Laboratory of Environmental Engineering, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an, 710055, China; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an, 710055, China.

PMID: 37699452
DOI: 10.1016/j.envpol.2023.122539

Abstract

Microalgal-bacterial symbiosis (MABS) system performs synergistic effect on the reduction of nutrients and carbon emissions in the water treatment process. However, antimicrobial agents are frequently detected in water, which influence the performance of MABS system. In this study, triclosan (TCS) was selected to reveal the effects and mechanisms of antimicrobial agents on MABS system. Results showed that the removal efficiencies of chemical oxygen demand, NH₄⁺-N and total phosphorus decreased by 3.0%, 24.0% and 14.3% under TCS stress. In contrast, there were no significant decrease on the removal effect of total nitrogen. Mechanism analysis showed that both the growth rate of microorganisms and the nutrients retention capacity of extracellular polymeric substances were decreased. The intracellular accumulation for nitrogen and phosphorus was promoted due to the increased cytomembrane permeability caused by lipid peroxidation. Moreover, microalgae were dominant in MABS system with ratio between microalgae and bacteria of more than 5.49. The main genus was Parachlorella, with abundance of more than 90%. Parachlorella was highly tolerant to TCS, which might be conductive to maintain its survival. This study revealed the nutrients pathways of MABS system under TCS stress, and helped to optimize the operation of MABS system.

Keywords: Bio-accumulation; Extracellular polymeric substance; Microbial community structure; Microbial growth; Nutrient removal.

MeSH terms

Anti-Infective Agents*
Bacteria / metabolism
Biomass
Microalgae* / metabolism
Nitrogen / analysis
Phosphorus / analysis
Symbiosis
Triclosan* / analysis

Substances

Triclosan
Nitrogen
Phosphorus
Anti-Infective Agents