Correlation between ethanol stress and cellular fatty acid composition of alcohol producing non-Saccharomyces in comparison with Saccharomyces cerevisiae by multivariate techniques

Abstract

Wine production is a complex process both from biochemical and microbiological point of view in which yeast plays a central role. The use of the wine yeast Saccharomyces cerevisiae and non- Saccharomyces yeasts as mixed starter cultures for wine fermentations is of increasing interest to enhance the quality of wine.The most common stress, yeast cells encounter during wine fermentation is the increase in ethanol concentration.To enhance ethanol tolerance, alteration in the cellular lipid composition is one of its defence mechanism. Ethanol tolerance and cellular fatty acid composition of alcohol producing non Saccharomyces forms were compared with enological strains of Sacccharomyces cerevisiae. Saccharomyces cerevisiae used for the study, tolerated 15 % of ethanol and the non Saccharomyces strains such as, Issatchenkia occidentalis and Issatchenkia orientalis tolerated 10 % of ethanol. On exposure of Saccharomyces cerevisiae to ethanol stress, the proportion of monounsaturated fatty acids increased with concomitant decrease in saturated fatty acids. Decrease in monounsaturated fatty acids, exhibited by non-Saccharomyces yeasts when exposed to ethanol stress, could be one of the reasons for their inability to withstand more than 10 % of alcohol. Multivariate techniques of data analysis - principal component analysis and linear discriminant analysis were employed in order to establish differentiation criteria as function of yeast strains, alcohol stress and their fatty acid profile. Based on the data, Chemometrics, such as principal component analysis and discriminant function analysis, can be successfully applied to fatty acid data to categorize the yeast.

Physiological and Metabolomic Analysis of Issatchenkia orientalis MTY1 With Multiple Tolerance for Cellulosic Bioethanol Production

“…The metabolomic analysis provided that the resistance against high temperature was primarily featured by the intracellular contents of fatty acids. The higher contents of the unsaturated fatty acids have been identified as a key molecular factor for various types of stress resistance such as oxidative stress, organic acids, and temperature . Especially, oleic acid and linoleic acid showed constantly high contents across the different temperature and growth phase (overall 50 times higher in I. orientalis MTY1 compared to S. cerevisiae D452‐2).…”

Selection of Mozzarella Cheese Whey Native Yeasts with Ethanol and Glucose Tolerance Ability

“…Non-Saccharomyces yeasts, for example, Hanseniaspora and Candida mostly not tolerant to 4-6% ethanol, anyway late research demonstrate the ethanol-resistance capacity like S.cereviseae [53] - [55]. H.guilliermondii and C.krusei can deliver unsaturated fats in the plasma layer as the systems to adjust the nearness of ethanol stretch [56]. The expansion in the extent of ergosterol or oleic corrosive in H.guilliermondii cells gives an incredible adjustment to high ethanol focus [57].…”

Process optimization, physicochemical characterization and antioxidant potential of novel wine from an underutilized fruit Carissa spinarum L. (Apocynaceae)

“…The temperature program followed wasI: 40 °C (1 minute hold) to 70 °C at a rate of 5 °C per min and to 220 °C at a rate of 25 °C per min for 3 min. The carrier gas used was nitrogen and flow rate was maintained at 1 mL per min with an injection volume of 0.5 µL (Archana et al, 2015).…”