Economic conversion of lignocellulosic biomass materials into bioethanol requires conversion of both C5 and C6 sugars during the fermentation following pretreatment and enzymatic hydrolysis. Conventional yeast Saccharomyces cerevisiae lacks the metabolic pathways necessary for conversion of C5 sugars into ethanol. While several genetically engineered strains have been shown to convert C5 sugars, little data exist in the public literature on actual performance of these strains with pretreated lignocellulosic materials.

Thermoanaerobacter BG1 is a thermophilic bacterium isolated from a hotspring on Iceland and having the ability to use both C5 and C6 sugars simultaneously. Strain BG1L1 is a lactate dehydrogenase deficient mutant produced in our laboratory. This strain has been tested with mixed straw as raw material in both laboratory and pilot scale over extended periods of time. Besides this the strain has further been tested in laboratory scale on a large variety of biomass material such as straw, bagasse, willow, soft and hard wood, corn fibers, corn cobs and DDGS.

In the presentation we will show data from experiments with BG1L1 growing on different hydrolysates as well as the performance of this strain with several sugars present. Especially the performance of the strain when grown on xylose and arabinose will be presented in detail showing the major potential for using this bacterium for conversion of corn cobs, corn fibers and DDGS.