title: Selection and adaptation of Saccharomyces cerevisae to increased ethanol tolerance and production.
abstract: A total of 24 yeast strains were tested for their capacity to produce ethanol, and of these, 8 were characterized by the best ethanol yields (73.11-8 1.78%). The most active mutant Saccharomyce s cerevisiae ER-A, resistant to ethanol stress, was characterized by high resistance to acidic (pH 1.0 and 2.0), oxidative (1 and 2% of H2O2), and high temperature (45 and 52 degrees C) stresses. During cultivation under all stress conditions, the mutants showed a considerably increased viability ranging widely from about 1.04 to 3.94-fold in comparison with the parent strain S. cerevisiae ER. At an initial sucrose concentration of 150 g/l in basal medium A containing yeast extract and mineral salts, at 300C and within 72 h, the most active strain, S. cerevisiae ER-A, reached an ethanol concentration of 80 g/1, ethanol productivity of 1.1 g/Il/h, and an ethanol yield (% of theoretical) of 99.13. Those values were significantly higher in comparison with parent strain (ethanol concentration 71 g/1 and productivity of 0,99 g/l/h). The present study seems to confirm the high effectiveness of selection of ethanol-resistant yeast strains by adaptation to high ethanol concentrations, for increased ethanol production.
authors.affiliation: Department of Industrial Microbiology, Maria Curie-Sklodowska University, Lublin, Poland. janek@poczta.umcs.lublin.pl
authors.forename: Jan
authors.initials: J
authors.lastname: Fiedurek
authors.forename: Marcin
authors.initials: M
authors.lastname: Skowronek
authors.forename: Anna
authors.initials: A
authors.lastname: Gromada
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects*; D000431:Ethanol / Q000494:pharmacology*; D005285:Fermentation; D010101:Oxygen Consumption / Q000187:drug effects; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000378:metabolism*
chemical_list: D000431:Ethanol