Modification of fatty acid composition of lipid accumulating yeasts with cyclopropene fatty acid desaturase inhibitors

Summary The effect of cyclopropene fatty acids, sterculic and malvalic, on the lipids of yeasts grown under nitrogen limiting, lipid accumulating, conditions was studied. The ratio of stearic to oleic acid showed a dose response effect, with an increase in stearic acid content as the dose of cyclopropene fatty acid increased, and a corresponding reduction in oleic acid. Linoleic and linolenic acids were not affected to the same extent. These effects are shown for the yeasts Candida sp. 107, Trichosporon cutaneum, and Rhodosporidium toruloides.     

The relationship between freezing resistance and fatty acid composition of yeasts

Abstract The relationship between freezing resistance and cellular long-chain fatty acid composition of 18 selected yeast strains was studied. All strains produced a series of saturated and unsaturated evennumbered fatty acids ranging from 14 to 20 carbons in length. The majority of the freeze-resistant yeasts were found among fermentative species with a content of oleic acid above 40%.     

The long-chain fatty acid composition of yeasts used in the brewing industry

Summary The cellular long-chain fatty acids of 69 strains of yeasts, representing 29 species associated with the brewing industry, were extracted by saponification and analyzed asmethyl esters by gas chromatography. The strains were characterized by the presence of palmitic, palmitoleic, stearic, oleic, linoleic and linolenic acid as the major fatty acids. The strains were divided into six groups on the basis of their fatty acid content. With this method it was possible to differentiate between the yeasts on species and, in some instances, on strain level.     

Long-chain fatty acid composition of selected genera of yeasts belonging to the Endomycetales

The cellular long-chain fatty acids of 36 strains representing 18 genera of the Saccharomycetaceae, Endomycetaceae, Metchnikowiaceae, Saccharomycodaceae, Schizosaccharomycetaceae and Dipodascaceae were extracted and analyzed as methyl esters by gas chromatography. On the basis of their fatty acid content the set of strains was divided into 6 groups, coinciding with the above families. The members of the Saccharomycetaceae (group I) had a high percentage of oleic acid while the strains classified under the Endomycetaceae (group II) and Metchnikowiaceae (group III) were characterized by oleic acid and linoleic acid as major fatty acids. The Saccharomycodaceae (group IV) had the highest percentage of palmitoleic acid. The Schizosaccharomycetaceae (group V) had the highest percentage of oleic acid, while the Dipodascaceae (group VI) were characterized by a high percentage of linoleic acid.     

Long-chain fatty acid composition of selected genera of yeasts belonging to the Endomycetales

The cellular long-chain fatty acids of 36 strains representing 18 genera of the Saccharomycetaceae, Endomycetaceae, Metchnikowiaceae, Saccharomycodaceae, Schizosaccharomycetaceae and Dipodascaceae were extracted and analyzed as methyl esters by gas chromatography. On the basis of their fatty acid content the set of strains was divided into 6 groups, coinciding with the above families. The members of the Saccharomycetaceae (group I) had a high percentage of oleic acid while the strains classified under the Endomycetaceae (group II) and Metchnikowiaceae (group III) were characterized by oleic acid and linoleic acid as major fatty acids. The Saccharomycodaceae (group IV) had the highest percentage of palmitoleic acid. The Schizosaccharomycetaceae (group V) had the highest percentage of oleic acid, while the Dipodascaceae (group VI) were characterized by a high percentage of linoleic acid.This article originally appeared in an incorrect form in Antonie van Leeuwenhoek, Vol. 52, No. 1.     

Effects of sodium chloride concentration on phospholipid fatty acid composition of yeasts differing in osmotolerance

The effect of growth medium NaCl concentration on the fatty acid composition of phospholipids of 3 strains of Saccharomyces cerevisiae and 6 osmotolerant yeast strains was examined. The S. cerevisiae strains were characterized by a high content of palmitoleic (C_16:1) acid and by having no polyunsaturated C₁₈ acids, whereas the osmotolerant strains had a low content of C_16:1 and a high proportion of polyenoic C₁₈ acids. An increase of the NaCl concentration from 0% to 8% resulted in a decrease of the cellular phospholipid content on a dry-weight basis, for all strains but one of the osmotolerant strains. For the S. cerevisiae strains increased salinity produced a slight decrease of the proportion of C₁₆ fatty acids with a concomitant increase of C₁₈ acids, whereas the osmotolerant strains showed an increase of the relative content of oleic acid (C_18:1) at the expense of the proportion of polyenoic C₁₈ acids.     

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

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.     

Unsaturated fatty acid composition of wild type and respiratory deficient yeasts after aerobic and anaerobic growth

An analysis is given of the fatty acid composition of 18 yeast species, predominantly of the genus Saccharomyces; respiratory deficient mutant strains are included. The results are discussed from chemotaxonomical and physiological viewpoints, with special attention to unsaturated fatty acids and their relation to the petite mutation. The fatty acid composition of anaerobically grown Saccharomyces cerevisiae remains restricted, as far as unsaturated fatty acids are concerned, to those added to the medium and it may thus differ considerably from the composition after aerobic growth. Depending on the acids added, the cells may contain either palmitoleic or linoleic acids as the sole unsaturated fatty acid after anaerobic growth and as the predominant unsaturated fatty acid after aerobic growth. In contrast to all other known eukaryotes, Schizosaccharomyces japonicus seems to possess an anaerobic pathway for synthesis of unsaturated fatty acids.     

Production of extracellular higher fatty acids by yeasts grown on hexadecanoic acid

Production of exocellular higher fatty acids by Candida yeasts was studied during their growth in a mineral medium with hexadecane. The qualitative and quantitative composition of exocellular higher fatty acids was investigated during cultivation of Candida lipolytica VCM Y 2378(695) under the conditions of different aeration (5 and 80% saturation of the medium with oxygen). Palmitic (C16:0), palmitooleic (C16:1), oleic (C18:1) and linoleic (C18:2) acids predominated among other higher fatty acids. The overall amount of fatty acids increased and the content of unsaturated fatty acids decreased when the yeast growth was limited with oxygen.     

Subgrouping of bacterial populations by cellular fatty acid composition

Abstract The cellular fatty acid composition of six bacterial species isolated from the seeds and leaves of sugar beet ( Beta vulgaris ) and from soil were analysed. The quantitative data from the fatty acid methyl ester (FAME) profiles were highly reproducible. Numerical analysis of Xanthomonas maltophilia . FAME profiles sub-grouped strains according to when they were isolated in the growing season. The analytical method used was sensitive enough to differentiate strains of Klebsiella terrigena isolated from either soil or leaves. The results from this study confirm reports that analyses of bacterial FAME composition were rapid to perform, specific and allowed differentiation of strains within the same species.     

Higher fatty acid composition of enterococci

The content of unsaturated fatty acids in enterococcal cells has been found to have no essential relation to the composition of the culture medium. When cultivated in the same media, S. faecium had the degree of lipid unsaturation 1.5-2 times higher than S. faecalis. Mobile enterococci are sharply differentiated from immobile species by the content of cyclopropanic acid with 19 carbon atoms, constitute a heterogenous group and consist of at least 2 taxons, differing in the content of acids with 18 carbon atoms and the degree of lipid unsaturation.     

Cellular fatty acid composition ofCorallococcus coralloides

The fatty acid composition of five strains ofCorallococcus coralloides and three reference species ofMyxococcus were determined by gas-liquid chromatography. Methyl esters of fatty acid containing from 12 to 22 carbon atoms were identified. The major fatty acids present were C₁₅ and C₁₇ saturated branched chain, and both C₁₆ saturated and unsaturated straight chain acids. The C₁₇ saturated branched and straight chain acids, which were in valuable concentration in species ofMyxococcus, were not, however, detected in all strains ofC. coralloides. The application of these results in the distinction ofC. coralloides from the genusMyxococcus is discussed.     

Growth, lipid accumulation, and fatty acid composition in obligate psychrophilic, facultative psychrophilic, and mesophilic yeasts

Obligate psychrophilic, facultative psychrophilic, and mesophilic yeasts were cultured in a carbon-rich medium at different temperatures to investigate whether growth parameters, lipid accumulation, and fatty acid (FA) composition were adaptive and/or acclimatory responses. Acclimation of facultative psychrophiles and mesophiles to a lower temperature decreased their specific growth rate, but did not affect their biomass yield (Y_X/S). Obligate and facultative psychrophiles exhibited the highest Y_X/S. Acclimation to lower temperature decreased the lipid yield (Y_L/X) in mesophilic yeasts, but did not affect Y_L/X in facultative psychrophilic ones. Similar Y_L/X were found in both groups of psychrophiles, suggesting that lipid accumulation is not a distinctive characteristic of adaptation to permanently cold environments. The unsaturation of FAs was one major adaptive feature of the yeasts colonizing permanently cold ecosystems. Remarkable amounts of α-linolenic acid were found in obligate psychrophiles at the expense of linoleic acid, whereas it was scarce or absent in all the other strains. Increased unsaturation of FAs was also a general acclimatory response of facultative psychrophiles to a lower temperature. These results improve the knowledge of the responses enabling psychrophilic yeasts to cope with the cold and may be of support for potential biotechnological exploitation of these strains.     

The fatty acid composition of leech lipids

• 1.1. The constituent fatty acids of the neutral and phospholipids of Macrobdella ditetra, Nephelopsis obscura, Philobdella gracilis and Hirudo medicinalis have been determined.
• 2.2. Unsaturated fatty acids predominated in both neutral and phospholipid fractions of all leech species examined.
• 3.3. Arachidonic acid (20:4) was the most prevalent fatty acid in all species, accounting for as much as 36.7% of the total phospholipid fatty acids.

     

Cellular fatty acid composition of Leuconostoc oenos

The cellular fatty acid composition of 70 lactic acid bacteria was examined by capillary gas chromatography. Fifty-four Leuconostoc oenos strains, including three reference, type strains from the other Leuconostoc spp., nine Pediococcus spp. and two Lactobacillus spp. were studied. Eighteen fatty acids were determined, of which 10 were identified by gas chromatography-mass spectrometry. The relative percentages of the 18 fatty acids of the Leuconostoc strains were analyzed numerically and grouped using the unweighted pair-group method. Results show that four clusters could be defined at r = 0.920, with five strains unassigned. The major fatty acids of the Leuc. oenos strains were found to be palmitic acid (C16:0), palmitoleic acid (C16:1–9), oleic acid (C18: 1–9), vaccenic acid (C18: 1–11), dihyrosterculic acid (C19-cyclopropane-9) and lactobacillic acid (C19-cyclopropane-11). It was mainly on the basis of the amounts of oleic acid and the C19-cyclopropane fatty acids that the strains of Leuc. oenos could be distinguished from each other. This is the first report of the occurrence of dihydrosterculic acid in lactic acid bacteria. For the majority of Leuc. oenos strains, the result obtained with the cellular fatty acid analysis confirmed the phenotypic relationships.     

Peculiarities of the fatty acid composition ofBdellovibrio

The fatty acid composition of twelve Bdellovibrio strains isolated upon the growth on bacteria of various taxonomic groups was studied. A dependence of the lipid composition of bdellovibrios on that of bacteria they were parasitizing on was shown. Data pointing to the selective incorporation of fatty acids of host bacteria by bdellovibrios were obtained. Bdellovibrio membranes were shown to contain monounsatured fatty acids with different positions of double bonds indicating that there are at least two alternative mechanisms of synthesis of these acids in the parasites.     

The fatty acid composition of fern lipids

Fatty acid compositions of the lipids isolated from the pinnae of four fern species show that they differ from those of the lipids in leaves of higher plants in having C-20 polyunsaturated acids, mainly arachidonic acid. As in higher plants, the ω-3 polyunsaturated acids are concentrated in the monogalactosyl diglycerides. Variations are found both in the fatty acid compositions and in the monogalactosyl/digalactosyl diglyceride ratio during the growing season.