Xylose and cellobiose fermentation by yeasts isolated from the Brazilian biodiversity
نویسندگان
چکیده
Background The production of fuel ethanol has become important in recent years due not only to the future depletion of fossil fuels, but also environmental concerns. An attractive source of raw material for ethanol production is the lignocellulosic biomass, composed of lignin, cellulose and hemicellulose. In the case of Brazil, the sugarcane bagasse is an interesting source of cellulose and hemicellulose, polymers that can be used in the fermentative process for fuel alcohol production [1]. Although the industrial yeast Saccharomyces cerevisiae efficiently ferments hexoses, this yeast is unable to ferment pentoses such as xylose (present in hemicellulose hydrolysates) or the disaccharide cellobiose (present in cellulose hydrolysates). Thus, we have characterized the enzymes and transport systems involved in xylose and cellobiose fermentation by yeasts species isolated in rotten wood from several Brazilian ecosystems [2-4].
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