title: Conversion of sugars present in rice hull hydrolysates into ethanol by Spathaspora arborariae, Saccharomyces cerevisiae, and their co-fermentations.
abstract: The production of ethanol by the new yeast Spathaspora arborariae using rice hull hydrolysate (RHH) as substrate, either alone or in co-cultures with Saccharomyces cerevisiae is presented. Cultivations were also carried out in synthetic medium to gather physiological information on these systems, especially concerning their ability to grow and produce ethanol in the presence of acetic acid, furfural, and hydroxymethylfurfural, which are toxic compounds usually present in lignocellulosic hydrolysates. S. arborariae was able to metabolize xilose and glucose present in the hydrolysate, with ethanol yields (Y(P/S)(et)) of 0.45. In co-cultures, ethanol yields peaked to 0.77 and 0.62 in the synthetic medium and in RHH, respectively. When the toxic compounds were added to the synthetic medium, their presence produced negative effects on biomass formation and ethanol productivity. This work shows good prospects for the use of the new yeast S. arborariae alone and in co-cultures with S. cerevisiae for ethanol production.
authors.affiliation: Biotechnology & Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, Porto Alegre, RS, ZC 91501-970, Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: da Cunha-Pereira
authors.forename: Lilian Raquel
authors.initials: LR
authors.lastname: Hickert
authors.forename: Nicole Teixeira
authors.initials: NT
authors.lastname: Sehnem
authors.forename: Priscila Brasil
authors.initials: PB
authors.lastname: de Souza-Cruz
authors.forename: Carlos Augusto
authors.initials: CA
authors.lastname: Rosa
authors.forename: Marco Antônio Záchia
authors.initials: MA
authors.lastname: Ayub
mesh_terms: D019149:Bioreactors; D001709:Biotechnology; D002851:Chromatography, High Pressure Liquid; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation / Q000502:physiology*; D005947:Glucose / Q000378:metabolism; D007700:Kinetics; D012275:Oryza / Q000737:chemistry*; D011492:Protein Hydrolysates / Q000032:analysis / Q000378:metabolism*; D004718:Saccharomycetales / Q000378:metabolism / Q000502:physiology*; D012639:Seeds / Q000737:chemistry*; D013045:Species Specificity; D014994:Xylose / Q000378:metabolism
chemical_list: D011492:Protein Hydrolysates; D000431:Ethanol; D014994:Xylose; D005947:Glucose