Influence of ethanol and temperature on the cellular fatty acid composition of Zygosaccharomyces bailii spoilage yeasts

Abstract

Changes in the fatty acid profile of Zygosaccharomyces bailii strains, isolated from different sources, after growth at increasing concentrations of ethanol and/or decreasing temperatures were determined. Differences in fatty acid composition between Zygosaccharomyces bailii strains at standard conditions (25°C, 0% initial ethanol) were observed and could be related to ethanol tolerance. Zygosaccharomyces bailii strain isolated from wine showed the highest ethanol tolerance in relation to growth rate. Surprisingly, an increase in ethanol concentration or a decrease in growth temperature caused a decrease in the degree of unsaturation of total cellular fatty acids. On the other hand, the mean chain length increased (high ethanol concentration) or decreased (low temperature) depending on the stress factor. When both stress situations (high ethanol concentration and low temperature) were present at the same time, the degree of unsaturation remained approximately constant. With decreasing temperatures, the C16/C18 ratio increased in studies of initial ethanol content below 5%, and above 5% ethanol, decreased.

Microbial and chemical changes during the spontaneous ensilage of grape pomace

“…These micro‐organisms are relatively common in winery installations and can produce unpleasant odours which cause deterioration of wine flavour ( Chatonnet et al . 1995 ; Couto and Huis in’t Veld 1995).…”

“…Also, spoilage wine yeasts such as species of Zygossaccaromyces or Dekkera appeared within the total Saccharomyces species population. These micro-organisms are relatively common in winery installations and can produce unpleasant odours which cause deterioration of wine flavour (Chatonnet et al 1995;Couto and Huis in't Veld 1995).…”

“…Two strains were identified as Zygosaccharomyces bailii (formerly known as Saccharomyces bailii). The presence of this species very often leads to secondary fermentation in wines, causing deterioration of wine flavour (Couto and Huis in't Veld 1995). The genus Dekkera included two species, which have also been reported as normal wine spoilage yeasts (Kalathenos et al 1995).…”

Effect of Ethanol Stress on Fermentation Performance of Saccharomyces cerevisiae Cells Immobilized on Nypa fruticans Leaf Sheath Pieces

“…Improvement in ethanol tolerance of free S. cerevisiae cells was previously explained through changes in fa y acid composition in cellular membrane (9,(24)(25)(26)(27)(28). Our preliminary studies showed that the mass fractions of palmitic (C16:0), stearic (C18:0), palmitoleic (C16:1) and Table 2.…”

Significance of age, temperature, and aeration of yeast cell culture for the biosorption of europium from aquatic systems

“…Beales [20] and Russell et al [21] have reported that the cell membrane of both bacteria and yeasts contain higher proportion of unsaturated fatty acids as the growth temperature decreases. Furthermore, a number of less reported alterations can occur such as, shortening in the mean fatty acid chain length, an increase in the amount of branch fatty acids, and a reduction in the proportion of cyclic fatty acids [20][21][22], all related to fatty acids. The decrease in the carbon chain of membrane acids may result in a slight decrease in the deprotonation constant (pK a ) of the corresponding functional group (carboxyl group) as this is the general trend comparing the pK a values of shortchain aliphatic carboxyl acids, e.g.…”