Fig. 2

Time-course batch fermentation evaluation of wild-type C. acetobutylicum and Δpks. a Culture density (measured as optical density at 600 nm, OD₆₀₀) (left axis) and pH (right axis) from batch fermentations of wild type and Δpks. b Production of acetone, butanol, and ethanol from batch fermentations of wild type and Δpks. c Production of acetate and butyrate from batch fermentations of wild type and Δpks. d Production of compounds 1–3 from batch fermentation of wild-type C. acetobutylicum ATCC 824. As indicated, the green region represents the acid production phase of the fermentation (acidogenesis), while the blue region represents the solvent production phase (solventogenesis). Error bars represent the standard deviation of values from duplicate fermentations. Experiments were repeated at least three times independently