|کد مقاله||کد نشریه||سال انتشار||مقاله انگلیسی||ترجمه فارسی||نسخه تمام متن|
|5144959||1496894||2018||8 صفحه PDF||سفارش دهید||دانلود کنید|
- Ferroglobus placidus and Geoglobus ahangari produce current at 80 and 85Â Â°C in MECs.
- These two iron-reducing archaea were grown on acetate.
- Maximum current densities were ~Â 0.6Â A/m2 using graphite anodes.
- Preliminary data suggest direct electron transfer and not mediated transfer.
Few microorganisms have been examined for current generation under thermophilic (40-65Â Â°C) or hyperthermophilic temperatures (â¥Â 80Â Â°C) in microbial electrochemical systems. Two iron-reducing archaea from the family Archaeoglobaceae, Ferroglobus placidus and Geoglobus ahangari, showed electro-active behavior leading to current generation at hyperthermophilic temperatures in single-chamber microbial electrolysis cells (MECs). A current density (j) of 0.68Â Â±Â 0.11Â A/m2 was attained in F. placidus MECs at 85Â Â°C, and 0.57Â Â±Â 0.10Â A/m2 in G. ahangari MECs at 80Â Â°C, with an applied voltage of 0.7Â V. Cyclic voltammetry (CV) showed that both strains produced a sigmoidal catalytic wave, with a mid-point potential of âÂ 0.39Â V (vs. Ag/AgCl) for F. placidus and âÂ 0.37Â V for G. ahangari. The comparison of CVs using spent medium and turnover CVs, coupled with the detection of peaks at the same potentials in both turnover and non-turnover conditions, suggested that mediators were not used for electron transfer and that both archaea produced current through direct contact with the electrode. These two archaeal species, and other hyperthermophilic exoelectrogens, have the potential to broaden the applications of microbial electrochemical technologies for producing biofuels and other bioelectrochemical products under extreme environmental conditions.
Journal: Bioelectrochemistry - Volume 119, February 2018, Pages 142-149