title: Ethanolic fermentation of acid pre-treated starch industry effluents by recombinant Saccharomyces cerevisiae strains.
abstract: Two industrial effluents, a pre-fermentation effluent and a post-fermentation effluent from a wheat starch production plant, were used as substrates for fuel ethanol production in anaerobic batch cultures using minimal nutritional amendment. The performances of three metabolically engineered xylose-utilizing Saccharomyces cerevisiae strains: TMB 3001 expressing XYL1, XYL2 and XKS1, redox metabolism modulated CPB.CR1 and glucose de-repressed CPB.CR2, as well as a reference strain CEN.PK 113-7D not fermenting xylose, were evaluated. For the recombinant strains a glucose consumption phase preceded the xylose consumption phase. In both effluents, biomass and ethanol production occurred predominantly during the glucose consumption phase, whereas xylitol and glycerol formation were predominant in the xylose consumption phase. Total specific ethanol productivities on glucose were 6-fold higher than on xylose in the pre-fermentation effluent and 15-fold higher than on xylose in the post-fermentation effluent. CPB.CR1 showed impaired growth compared to the two other xylose-utilizing strains, but displayed 18% increased ethanol yield in the post-fermentation effluent.
authors: Center for Microbial Biotechnology, Technical University of Denmark, BioCentrum-DTU, Building 223, DK-2800 Kgs, Lyngby, Denmark.
authors: Jesus
authors: J
authors: Zaldivar
authors: Christophe
authors: C
authors: Roca
authors: Caroline
authors: C
authors: Le Foll
authors: Bärbel
authors: B
authors: Hahn-Hägerdal
authors: Lisbeth
authors: L
authors: Olsson
mesh_terms: D018533:Biomass; D019149:Bioreactors; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D013045:Species Specificity; D013213:Starch / Q000378:metabolism*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism
chemical_list: D014874:Water Pollutants, Chemical; D000431:Ethanol; D013213:Starch; D014994:Xylose; D005947:Glucose