Autotrophic (C1-gas) versus heterotrophic (fructose) accumulation of acetic acid and ethanol in Clostridium aceticum. (October 2021)

• Record Type: Journal Article
• Authors: Arslan, Kübra; Veiga, María C.; Kennes, Christian
• Is Part Of: Bioresource technology. Volume 337(2021)
• Publication Date: 2021-10
• Subjects: Carbon monoxide -- Carbon dioxide -- Solventogenesis -- Syngas -- Wood-Ljungdahl pathway; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2021.125485
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: 4.4 g·L −1 ethanol production from CO was possible when the pH was not regulated. Medium acidification resulted in ethanol production from CO but not from fructose. The carbon source affects pH-stimulated solvent production patterns in C. aceticum. At optimum pH, strong formic acid inhibition occurred during fructose fermentation. Abstract: The influence of the carbon source on the metabolism and growth of Clostridium aceticum was investigated, supplying either CO or fructose as sole carbon source. The acid and solvent production patterns were determined under either autotrophic or heterotrophic conditions, elucidating the effect of pH on the substrate's bioconversion pattern. The highest maximum specific growth rate was observed with CO, under the organism's optimal growth conditions, reaching 0.052 h −1 and an acetic acid concentration of 18 g·L −1 . The production of 4.4 g·L −1 ethanol was also possible, after medium acidification, during CO bioconversion. Conversely, formic acid inhibition was observed during fructose fermentation under optimal growth conditions. In the latter experiments, it was not possible to stimulate solvent production when growing C. aceticum on fructose, despite applying the same medium acidification strategy as with CO, showing the selective effect of the carbon source (autotrophic vs heterotrophic) on the metabolic pattern and solventogenesis.