The Need

Acetone-Butanol-Ethanol (ABE) Fermentation is one of two methods to produce butanol from biomass feedstocks. Various active enzymes or acids are exposed to a biomass feedstock and subsequently produce primarily acetone, butanol and ethanol. Previous attempts in the industry to use Clostridium strains to ferment butanol were plagued by high costs, relatively low-yields, sluggish fermentations, inhibition of the end product, and phage infections. Re-engineering Clostridium to increase yield of butanol over other undesired products would greatly improve biomass to product conversion efficiency.

The Technology

Researchers at The Ohio State University, led by Dr. Shang-Tian Yang, have developed novel strains of Clostridium that produce significantly more n-butanol than their parent strains when exposed to biomass. These strains can be used for industrial biobutanol production to enable a more economical conversion of biomass feedstocks. The Clostridium strains are significantly more robust than previous conceptions and less sensitive to environmental factors. This durability enables the bacteria to digest higher quantities of biomass before dying, resulting in greater butanol generation compared to other mutant Clostridium strains.

Commercial Applications

• Butanol production
• Biofuels
• Aviation jet fuel

Benefits/Advantages

• Less sensitive to environmental factors than wild type
• Demonstrates robustness and tolerance in sugarcane bagasse hydrolysate
  • 9.44 g/L ABE production compared to 2.57 g/L of wild type
• More stable and consistent fermentation than wild type
  • Able to produce butanol more consistently under conditions where the wild type often failed due to acid crash
• Converts acids produced into solvents more efficiently than wild type under all scenarios evaluated
• Stably produced 9.44-13.78 g/L solvents under all conditions evaluated