Inferring ethanol tolerance of Saccharomyces and non-Saccharomyces yeasts by progressive inactivation.
The kinetics of cell inactivation in the presence of ethanol at 20, 22.5% and 25% (v/v), was measured by progressive sampling and viable counting, and used as an inference of the ethanol resistance status of five non-Saccharomyces strains and one strain of Saccharomyces cerevisiae. The capacity of standard inocula of the same strains to establish growth at increasing initial ethanol concentrations was employed as a comparison. The effect of various different pre-culture conditions on the ethanol resistance of the 6 strains was analysed by the cell inactivation method and by the cell growth method. Exposing cells to 25% (v/v) ethanol for 4 min enabled the differentiation of the yeasts in terms of their resistance to ethanol. The results suggest that the two methods are generally concordant and that the cell inactivation method can, thus, be used to infer ethanol resistance of yeast strains.
Pina
Cristina
C
Escola Superior de Biotecnologia, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal. cristina@morango.esb.ucp.pt
Couto
José António
JA
António
José
J
Hogg
Tim
T
D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D015169:Colony Count, Microbial / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D000431:Ethanol / Q000494:pharmacology*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D015003:Yeasts / Q000166:cytology / Q000187:drug effects* / Q000502:physiology
D000431:Ethanol