Hydrogen-based syntrophy in an electrically conductive biofilm anode

Bipro Ranjan Dhar, Jeong Hoon Park, Hee-Deung Park, Hyung Sool Lee

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

We experimentally and theoretically investigated implications of H2 and a rate-limiting step in a mixed-culture biofilm anode fed with n-butyrate, one of the poorest substrates to exoelectrogens. Acetate and i-butyrate were formed as intermediates during anaerobic degradation of n-butyrate, which suggested oxidative acetogenesis of n-butyrate in syntrophy with H2 scavengers in the biofilm anode. Methane was not detected in an anode chamber, and no current was generated in the biofilm anode using H2 as the electron donor. These results indicated that acetogens would be a main H2 consumer in the biofilm. Pyrosequencing data showed dominance of Geobacter in the biofilm anode (83.6% of total sequences), along with Sphaerochaeta and Treponema, which supports the syntrophy between exoelectrogens and acetogens. Electrical conductivity of the butyrate-fed biofilm anode was as high as 0.67 mS/cm, demonstrating that EET does not limit current density in the biofilm. In-situ monitoring of dissolved H2 concentration proved H2 production (up to 12.4 µM) and consumption during current generation in the biofilm, which supports significance of H2–based syntrophy in the electrically conductive biofilm using n-butyrate as the primary electron donor.

Original languageEnglish
Pages (from-to)208-216
Number of pages9
JournalChemical Engineering Journal
Volume359
DOIs
Publication statusPublished - 2019 Mar 1

    Fingerprint

Keywords

  • Acetogenesis
  • Biofilm conductivity
  • Butyrate
  • Direct interspecies electron transfer
  • Geobacter
  • Hydrogen

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

Cite this