S162: Development of Cargill’s CB1 Platform for Cellulosic Ethanol Production

The US Government’s Renewable Fuel Standard is calling for the production of 36 billion gallons of renewable biofuels by 2022. With the issues surrounding ethanol production from food crops, fuels derived from cellulosic biomass figure to be a key component in meeting these biofuel requirements.  Many obstacles sit in the way of a cost effective method for cellulosic ethanol, including the identification and development of biocatalysts that demonstrate not only high titer and yield from pentose sugars, but tolerance to ethanol, low pH, high temperature, and toxic inhibitors found in biomass hydrolysates.  These characteristics would reduce both capital and operating costs by eliminating the need for costly detoxification steps.  Through an extensive strain development program, Cargill has developed its proprietary yeast, CB1, into a robust biocatalyst for the fermentation of ethanol from cellulosic biomass. Metabolic engineering, mutagenesis and selection, and evolution have been used to create biocatalysts with high ethanol production rates and yields from non-detoxified corn stover hydrolysate.  Cargill offers a library of strains which can be screened to identify the highest performing strain for a specific hydrolysate process, including biocatalysts that can utilize both xylose and arabinose.  The cellulosic capabilities, along with the knowledge and tools developed for this yeast platform, make this organism an exceptional biocatalyst for a variety of bio-based fuels and chemicals.