High current density via direct electron transfer by hyperthermophilic archaeon, Geoglobus acetivorans, in microbial electrolysis cells operated at 80 °C


Bioelectrochemistry, vol.145, 2022 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 145
  • Publication Date: 2022
  • Doi Number: 10.1016/j.bioelechem.2022.108072
  • Journal Name: Bioelectrochemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, Compendex, EMBASE, MEDLINE, Veterinary Science Database
  • Keywords: Bioelectrochemical systems, Microbial electrolysis cell, Hyperthermophilic archaea, Geoglobus acetivorans, Direct electron transfer, WASTE-WATER TREATMENT, HYDROGEN-PRODUCTION, BIOHYDROGEN PRODUCTION, ELECTRICITY PRODUCTION, FERROGLOBUS-PLACIDUS, ANODE, BACTERIUM, FERMENTATION, TECHNOLOGIES, GENERATION
  • Middle East Technical University Affiliated: Yes


© 2022 Elsevier B.V.Utilization of hyperthermophilic electro-active microorganisms in microbial electrolysis cells (MECs) that are used for hydrogen production from organic wastes offers significant advantages, such as increased reaction rate and enhanced degradation of insoluble materials. However, only a limited number of hyperthermophilic bioelectrochemical systems have been investigated so far. This study is the first to illustrate hydrogen production in hyperthermophilic MECs with a maximum rate of 0.57 ± 0.06 m3 H2/m3d, where an iron reducing archaeon, Geoglobus acetivorans, was used as inoculum. In fact, this is the first study to report that G. acetivorans, as the fourth hyperthermophilic electro-active archaeon. In single chamber MECs operated at 80 °C with a set potential of 0.7 V, a peak current density of 1.53 ± 0.24 A/m2 has been attained and this is the highest record of current produced by pure culture hyperthermophilic microorganisms. Turnover cyclic voltammetry curve illustrated a sigmoidal shape (midpoint of −0.40 V vs. Ag/AgCl), and together with linear relation of scan rate and peak anodic current, proves the biofilm attachment to the anode and its capability of direct electron transfer. Along with simple substrate (acetate), G. acetivorans effectively utilized dark fermentation effluent for hydrogen production in MECs.