Polarized potential and electrode materials implication on electro-fermentative di-hydrogen production: Microbial assemblages and hydrogenase gene copy variation

Bioresour Technol. 2016 Jan:200:691-8. doi: 10.1016/j.biortech.2015.10.091. Epub 2015 Oct 31.

Abstract

This study examined the changes in microbial diversity in response to different electrode materials viz., stainless steel mesh (SS) and graphite plate as anodes in two microbial electrolysis cell (MEC) each poised at 0.2V, 0.4V, 0.6V and 0.8V. Changes in microbiota prior to and after pretreatment along with microbiota enriched in response to various poised potentials with SS and graphite are monitored by 16S rRNA gene based DGGE profiling. Significant shifts in microbial community were noticed at all these experimental conditions. Correspondingly, the level of hydrogenase belonging to genera Bacillus, Pseudomonas, Rhodopseudomonas and Clostridium was studied by quantitative real time PCR (RT-PCR) at various applied potentials. DGGE based 16S rRNA gene profiling revealed enriched members belonging to phylum Firmicutes predominantly present at 0.8V in both MECs contributing to high hydrogen production. This study first time explored the growth behavior of mixed consortia in response to poised potentials and electrode materials.

Keywords: DGGE profiling; Electrode materials; Microbial electrolysis cell; Poised potential; qRT-PCR.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / genetics
  • Bacteria / metabolism*
  • Biodiversity
  • Bioelectric Energy Sources / microbiology
  • Bioreactors / microbiology
  • Denaturing Gradient Gel Electrophoresis
  • Electrodes
  • Electrolysis / methods*
  • Fermentation*
  • Gene Dosage*
  • Genes, Bacterial
  • Hydrogen / metabolism*
  • Hydrogenase / genetics*
  • Oxidation-Reduction
  • Phylogeny
  • RNA, Ribosomal, 16S
  • Wastewater / chemistry

Substances

  • RNA, Ribosomal, 16S
  • Waste Water
  • Hydrogen
  • Hydrogenase