Hydrogen and formate production and utilisation in the rumen and the human colon

William J. Kelly, Roderick I. Mackie, Graeme T. Attwood, Peter H. Janssen, Tim A. McAllister, Sinead C. Leahy

Research output: Contribution to journalReview articlepeer-review


Molecular hydrogen (H2) and formate (HCOO) are metabolic end products of many primary fermenters in the mammalian gut. Both play a vital role in fermentation where they are electron sinks for individual microbes in an anaerobic environment that lacks external electron acceptors. If H2 and/or formate accumulate within the gut ecosystem, the ability of primary fermenters to regenerate electron carriers may be inhibited and microbial metabolism and growth disrupted. Consequently, H2- and/or formate-consuming microbes such as methanogens and homoacetogens play a key role in maintaining the metabolic efficiency of primary fermenters. There is increasing interest in identifying approaches to manipulate mammalian gut environments for the benefit of the host and the environment. As H2 and formate are important mediators of interspecies interactions, an understanding of their production and utilisation could be a significant entry point for the development of successful interventions. Ruminant methane mitigation approaches are discussed as a model to help understand the fate of H2 and formate in gut systems.

Original languageEnglish (US)
Article number22
JournalAnimal Microbiome
Issue number1
StatePublished - Dec 2022


  • Colon
  • Formate
  • Homoacetogens
  • Hydrogen
  • Methane
  • Methanogens
  • Mitigation
  • Rumen

ASJC Scopus subject areas

  • Microbiology (medical)
  • Animal Science and Zoology
  • Agricultural and Biological Sciences (miscellaneous)
  • veterinary (miscalleneous)


Dive into the research topics of 'Hydrogen and formate production and utilisation in the rumen and the human colon'. Together they form a unique fingerprint.

Cite this