8-63: Ethanol production from lignocellulose with pentose fermenting yeast

The demand for renewable biofuels was initiated by the realization of the unsustainable future associated with fossil fuels. The first generation of renewable bioethanol production utilized sugar and starch based plant biomass, which has the drawback that it competes with the world’s supply of raw materials for food and feed. C5 Ligno Technologies (C5LT) focuses research and development on second generation bioethanol production from renewable, sustainable, and non-food-and-feed competing biomass; lignocellulose. Lignocellulose raw materials contain a mixture of sugars; monomers, dimers, and polymers, of both hexose and pentose sugars. The yeast Saccharomyces cerevisiae has a natural ability to efficiently ferment hexose sugars, but to further increase ethanol yields from lignocellulose, the ability to ferment pentose sugars has to be introduced. With gene-constructs from C5LT pentose fermentation can be achieved in any industrial yeast strain, which can be individually tailored for different raw materials and process conditions. More specifically, at C5LT focus lies on rational engineering of the reductive/oxidative xylose uptake pathway. The performance of C5LT strains in hydrolysate from different lignocellulose raw materials will be presented.