Biobutanol production by a new aerotolerant strain of Clostridium acetobutylicum YM1 under aerobic conditions

A newly isolated strain of Clostridium acetobutylicum YM1 has a unique property of producing biobutanol from glucose under aerobic conditions. This strain exhibited the capability to grow and produce high concentrations of biobutanol under different concentrations of dissolved oxygen (DO). The growth profile and solvent production in a 5 L bioreactor were similar under anaerobic and aerobic conditions (100% initial DO saturation), and the final biobutanol production was 12.18 and 12.30 g/L, respectively. The addition of reducing chemical agents, without creating anaerobic conditions, to the culture of YM1 enhanced the production of biobutanol. Strain YM1 possesses different enzymes that are responsible for oxygen scavenging, such as superoxide dismutase (SOD), catalase and NADH/NADPH oxidases. This study provides a simple operation strategy for more efficient biobutanol production by using an aerotolerant strain of C. acetobutylicum YM1 without the need to flush the medium with nitrogen gas to ensure anaerobic conditions.