Importance of sulfide interaction with iron as regulator of the microbial community in biogas reactors and its effect on methanogenesis, volatile fatty acids turnover, and syntrophic long-chain fatty acids degradation

Abstract

The inhibitory effects of sulfide on microbial processes during anaerobic digestion have been widely addressed. However, other effects of sulfide are less explored, given that sulfide is a potential sulfur source for microorganisms and its high reactivity triggers a suit of abiotic reactions. We demonstrated that sulfide interaction with Fe regulates the dynamics and activities of microbial community during anaerobic digestion. This was manifested by the S:Fe molar ratio, whose increase adversely influenced the acetoclastic methanogens, Methanosaeta, and turnover of acetate. Dynamics of hydrogenotrophic methanogens, Methanoculleus and Methanobrevibacter, were presumably influenced by sulfide-induced changes in the partial pressure of hydrogen. Interestingly, conversion of the long-chain fatty acid (LCFA), oleate, to methane was enhanced together with the abundance of LCFA-degrading, beta-oxidizing Syntrophomonas at an elevated S:Fe molar ratio. The results suggested that sulfur chemical speciation is a controlling factor for microbial community functions in anaerobic digestion processes. (C) 2016, The Society for Biotechnology, Japan. All rights reserved.

Keywords

Anaerobic digestion; Sulfide; Iron; Microbial community; Sewage sludge

Published in

Journal of Bioscience and Bioengineering
2017, volume: 123, number: 5, pages: 597-605
Publisher: SOC BIOSCIENCE BIOENGINEERING JAPAN

SLU Authors

• Skyllberg, Ulf

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Renewable Bioenergy Research

Publication identifier

• DOI: https://doi.org/10.1016/j.jbiosc.2016.12.003

Permanent link to this page (URI)

https://res.slu.se/id/publ/83022