title: Membrane lipid variability in Saccharomyces cerevisiae wine strains rehydrated in the presence of metabolic activators.
abstract: Slight variations in lipid composition of wine yeast membranes can alter some essential functions including selective nutrient transport and ion permeability. The absence of oxygen during alcoholic fermentation inhibits fatty acid desaturation and sterol biosynthesis, thereby reducing the stress resistance of yeast cells. In this work, membrane lipids in two commercial active dry yeast strains rehydrated in the presence of three activators (ergosterol, tetrahydrofolic acid, and manganese) were studied. Each was assayed at three different concentrations. The effect of these activators on the phospholipid, neutral lipid, and fatty acid contents in cell membranes was assessed. Also, cell viability and fermentation kinetics were determined. Ergosterol was found to shorten the lag phase and improve cell viability and membrane lipid composition; tetrahydrofolic acid raised neutral lipid levels; and manganese(II) increased cell viability and modified phospholipid composition and linoleic acid concentration. All activators interacted with yeasts in a strain-dependent way.
authors.affiliation: Tecnologı́a de Alimentos, IRICA, Universidad de Castilla-La Mancha , Edificio Marie Curie, Avenida Camilo José Cela 10, 13071 Ciudad Real, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Díaz-Hellín
authors.forename: Sergio
authors.initials: S
authors.lastname: Gómez-Alonso
authors.forename: Anna
authors.initials: A
authors.lastname: Borrull
authors.forename: Nicolas
authors.initials: N
authors.lastname: Rozès
authors.forename: Ricardo
authors.initials: R
authors.lastname: Cordero-Otero
authors.forename: Juan
authors.initials: J
authors.lastname: Úbeda
mesh_terms: D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D004875:Ergosterol / Q000378:metabolism; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism; D005285:Fermentation; D008563:Membrane Lipids / Q000737:chemistry / Q000378:metabolism*; D050296:Microbial Viability; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D013763:Tetrahydrofolates / Q000378:metabolism; D014920:Wine / Q000382:microbiology*
chemical_list: D005227:Fatty Acids; D008563:Membrane Lipids; D013763:Tetrahydrofolates; C030371:5,6,7,8-tetrahydrofolic acid; D004875:Ergosterol