Overlooked roles of improved substrates functions in remodeling microbial community and driving metabolic traits during sludge fermentation triggered by surfactants and antibiotics co-existence

Xiaoshi Cheng; Le Zhang; Zhicheng Wei; Xinyi Liu; Xiong Shi; Xuran Liu; Jiashun Cao; Qian Feng; Fang Fang; Jingyang Luo

doi:10.1016/j.jhazmat.2024.136617

Overlooked roles of improved substrates functions in remodeling microbial community and driving metabolic traits during sludge fermentation triggered by surfactants and antibiotics co-existence

J Hazard Mater. 2024 Nov 22:482:136617. doi: 10.1016/j.jhazmat.2024.136617. Online ahead of print.

Authors

Xiaoshi Cheng¹, Le Zhang², Zhicheng Wei¹, Xinyi Liu¹, Xiong Shi³, Xuran Liu⁴, Jiashun Cao¹, Qian Feng¹, Fang Fang¹, Jingyang Luo⁵

Affiliations

¹ Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing 210098, PR China.
² Academy of Environmental Planning & Design, Co., Ltd., Nanjing University, Nanjing 210093, PR China.
³ National Engineering Research Center of Eco-Environment Protection for Yangtze River Economic Belt, China Three Gorges Corporation, Wuhan 430014, PR China.
⁴ Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing 210098, PR China.
⁵ Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing 210098, PR China. Electronic address: luojy2016@hhu.edu.cn.

PMID: 39579691
DOI: 10.1016/j.jhazmat.2024.136617

Abstract

Sludge anaerobic fermentation is a pivotal route to transit wastewater treatment plants towards energy-neutral and resource recovery-oriented plants, while the overall efficiency is commonly restrained by co-exist contaminants. This study unveiled the cooperative effect of sulfadiazine (SDZ) and linear alkylbenzene sulfonates (LAS) in driving volatile fatty acids (VFAs) biosynthesis during waste activated sludge (WAS) anaerobic fermentation. The VFAs remarkably elevated to 1189 mg COD/L in LAS/SDZ, which was approximately 1.3-3.2 folds of SDZ and LAS. SDZ and LAS synergistically disintegrated extracellular polymeric substances to provide fermentation substrates. These changes altered microbial population and enhanced microbial networks interconnection. Moreover, the proteins released from WAS might facilitate electron transfer among microorganisms. The functional anaerobic species, including hydrolytic-acidogenic bacteria (e.g., Veillonellaceae and Lactobacillus) and electroactive bacteria (e.g., Parabacteroides and Fonticella), were enriched. Also, the metabolic traits responsible for transmembrane transport, intracellular metabolism, VFAs biosynthesis and electron transfer-related process were strengthened with the upregulation of functional genes. Further analysis revealed that the functional anaerobic species activated quorum sensing and two-component systems to counteract unfavorable LAS/SDZ stress and maintain high metabolic activities. This work elucidated the overlooked roles of substrates in modulating anaerobic consortia and metabolic traits in sludge fermentation systems with mixed pollutants stressing.

Keywords: Anaerobic fermentation; Co-contaminants; Electron transfer; Metabolic pathways; Volatile fatty acids.