Relationship between ethanol tolerance, H+-ATPase activity and the lipid composition of the plasma membrane in different wine yeast strains

Ethanol tolerance, ATPase activity and the lipid composition of the plasma membrane to study potential relationship among them were examined in five different wine yeast strains. Yeast cells were subjected to ethanol stress (4% v/v). Principal component analysis of the results revealed that the wine yeasts studied can be distinguished in terms of ATPase activity and oleic acid (C18:1), and palmitoleic acid (C16:1), in plasma membrane. Multiple regression analysis was used to identify a potential influence of some components of the plasma membrane on ethanol tolerance and ATPase activity. Based on the results, the ergosterol, oleic acid and palmitoleic acid are highly correlated with ATPase activity and ethanol tolerance. Ethanol tolerance and the ATPase activity of the plasma membrane were correlated at the 96.64% level with the oleic acid and ergosterol in plasma membrane. The Saccharomyces cerevisiae var. capensis flor yeast strain, which exhibited the highest ergosterol concentration in plasma membrane when grown in the presence of 4% v/v ethanol, was found to be the most ethanol-tolerant.