Effect of granular activated carbon and chloroform on chain elongation with simple substrate ethanol and acetate

Lin Li; Linji Xu; Junguo He; Qiang He; Jie Zhang

doi:10.1016/j.envres.2023.115324

Effect of granular activated carbon and chloroform on chain elongation with simple substrate ethanol and acetate

Environ Res. 2023 Mar 15:221:115324. doi: 10.1016/j.envres.2023.115324. Epub 2023 Jan 18.

Authors

Lin Li¹, Linji Xu², Junguo He³, Qiang He⁴, Jie Zhang⁵

Affiliations

¹ Key Laboratory of the Three Gorges Reservoir Region's Eco-environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, 400045, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China. Electronic address: lilin781@sina.com.
² Key Laboratory of the Three Gorges Reservoir Region's Eco-environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, 400045, China. Electronic address: lin_ji_good@126.com.
³ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Civil Engineering, Guangzhou University, Guangzhou, 510006, China.
⁴ Key Laboratory of the Three Gorges Reservoir Region's Eco-environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
⁵ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.

PMID: 36669585
DOI: 10.1016/j.envres.2023.115324

Abstract

Chain elongation is a promising technology for production of medium-chain fatty acids (MCFAs). Granular activated carbon (GAC) is commonly used in anaerobic fermentation. Low level CHCl₃ can inhibit methanogenesis and homoacetogenesis at the same time. However, the effect of them on chain elongation performance with highly enriched consortia and simple substrate (i.e., ethanol and acetate) was still unclear. Hence, the effects of CHCl₃ and on MCFAs production and the microbial community was studied here. CHCl₃ displayed fatal effect on chain elongation system when its concentration was higher than 0.1% v/v. 0.05% v/v CHCl₃ was enough to inhibit homoacetogens and further decreased the caproate production efficiency without altering the core bacteria tremendously. GAC was found to be adverse for chain elongation with simple substrate (i.e., ethanol and acetate) and highly enriched microbial consortia dominated by Clostridium sensu stricto, less than 20% electrons were finally distributed in caproate. It might be attributed to other electron consuming activities induced by GAC.

Keywords: Caproate; Homoacetogenesis; Medium chain fatty acids; Methanogenesis inhibitor; Microbial community.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Acetates
Bioreactors
Caproates*
Charcoal
Chloroform
Ethanol*
Fatty Acids
Fermentation

Substances

hexanoic acid
Caproates
Ethanol
Chloroform
Charcoal
Acetates
Fatty Acids