Acidithiobacillus ferrooxidans as a bioelectrocatalyst for conversion of atmospheric CO 2into extracellular pyruvic acid

Abstract

This study investigated the ability of the bacterium Acidithiobacillus ferrooxidans to convert CO 2 into organic compounds in batch culture and during electrochemical cultivation. Metabolites secreted into the culture medium were detected and analyzed by HPLC and mass spectroscopy, which revealed that pyruvic acid was one of the organic acids present in both cultures. We found that although pyruvic acid acted as a strong inhibitor for microbial growth in batch cultures, microbial CO 2 fixation activity in electrochemical cultures was not significantly affected by the addition of excess pyruvic acid. Together, these findings indicate that A. ferrooxidans is a promising bioelectrocatalyst for the conversion of CO 2 into extracellular organic compounds. © The Electrochemical Society of Japan All rights reserved.