Newly isolated yeasts from Tunisian microhabitats: Lipid accumulation and fatty acid composition

Abstract

Newly isolated yeasts from different Tunisian microhabitats, such as soil, milk, olive brine, vinegar, and from olive mill wastewater‐contaminated biotopes were extensively studied for their biochemical arsenal and morphological features, i.e. cell, ascospore, and lipid body morphology. All strains were classified into the Ascomycota phylum. However, they showed great functional diversity, including different morphological and biochemical features, lipid production ability, and fatty acid profiles. Accordingly, the strains were placed in three different groups: Group I, which includes Candida species; Group II (Pichia and related); and Group III (Kluyveromyces marxianus strain CC1). Group I and II were characterized by a high percentage of oleic acid (41.6–65.3% of total lipids) while in Group III, linoleic acid was the major fatty acid (37.2%). Members of Group I and II were further grouped into subgroups according to their fatty acid composition. Among the newly isolated strains, Pichia etchellsii BM1 was able to accumulate around 25% wt/wt lipid per dry cell mass and thus characterized as oleaginous. Some other strains, such as Candida metapsilosis strain EL2, C. parapsilosis strain LV2, C. pararugosa strain BM24, and K. marxianus strain CC1, which are able to produce extracellular lipases, may be of interest for specific environmental applications and/or for the production of novel lipases.

Effect of Selenium on Lipid and Amino Acid Metabolism in Yeast Cells

“…Large droplets of TAGs can occupy the larger part of a cell. The main fatty acid found in yeast lipids is oleic acid (C18:1), and its share can be even higher than 70% of total fatty acid [ 14 , 53 ]. The biomass of C .…”

Isolation, identification and screening of yeasts towards their ability to assimilate biodiesel‐derived crude glycerol: microbial production of polyols, endopolysaccharides and lipid

“…In most cases, yeast strains performing the previously mentioned conversions (Gly conversion into polyols or SCO) are either mutants or are wild‐type strains originated from official culture collections (Koganti et al ; Tomaszewska et al ; Koganti and Ju ; Mirończuk et al ; Uprety et al , b). Although, in the last years there is a continuous growing interest regarding the potential of using natural new yeast isolates from different environments which may owe important attributes such as genetic stability, environmental adaptation and biotechnological characteristics that maybe used to different applications (Spadaro and Gullino ; Gil‐Serna et al ; Liu et al ; Ayadi et al , ; Arous et al ; Maina et al ). Moreover, concerning several types of fermentation processes (i.e.…”

Identification and Characterization of Phospholipids with Very Long Chain Fatty Acids in Brewer's Yeast

“…Although their yeast content, including the content of fatty acids (FA) has been described in many reviews [1][2][3][4][5][6], no one has so far paid attention to the content of very long chain fatty acids (VLCFA). Although their yeast content, including the content of fatty acids (FA) has been described in many reviews [1][2][3][4][5][6], no one has so far paid attention to the content of very long chain fatty acids (VLCFA).…”

“…Yeasts, especially those that are a byproduct after beer production, are often used as a dietary supplement, whether by humans or by livestock under different names such as Natural Brewers Yeast, Bierhefe Tabletten, Brewers Yeast Tablets, Brewer's Yeast, Debittered Brewer's Yeast, Pangamin, etc. Although their yeast content, including the content of fatty acids (FA) has been described in many reviews [1][2][3][4][5][6], no one has so far paid attention to the content of very long chain fatty acids (VLCFA). More than 40 years ago, Welch and Burlingame [7] described the presence of these acids up to tetratriacontanoic acid in the yeast species Saccharomyces cerevisiae, but monounsaturated FA only up to 28:1 (octacosenoic acid) were identified.…”