• Korean Journal of Plant Resources
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• v.32 no.5
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• pp.415-422
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• 2019

Rhodosporidium toruloides has been known as an in vitro model of fat metabolism. The purpose of this study is to identify the triglyceride inhibitory effects of hot water extracts from beetroot using R. toruloides. The triglyceride content of oleaginous yeast cultured from YPD culture medium were regulated by treatment of beet root hot water and ethanol extract, respectively. In addition, the number of cells in the oleaginous yeast was 10.48, 8.46, 12.40, 12.80 and $8.24{\times}10^3cell/mL$. The treatment of hot water extract of beet root increased total lipid content of oleaginous yeast in dose dependently. Moreover, the triglyceride content of oleaginous yeast was decreased by hot water extract of beet root extract, respectively. The fat droplet in the oleaginous yeast decreased according to the concentration of hot water extracts from beetroot. The ratio of increase in the number of cells in the oleaginous yeast were increased dose-dependently by treatment of hot water extract from beetroot compared with control group. The free fatty acid and total carotenoid contents were increased concentration-dependently by treatment of hot water extracts from beetroot. These study results indicate that hot water extracts from beetroot has a triglyceride inhibitory effects.

• Mycobiology
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• v.50 no.1
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• pp.66-78
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• 2022

The identification of oleaginous yeast species capable of simultaneously utilizing xylose and glucose as substrates to generate value-added biological products is an area of key economic interest. We have previously demonstrated that the Cutaneotrichosporon dermatis NICC30027 yeast strain is capable of simultaneously assimilating both xylose and glucose, resulting in considerable lipid accumulation. However, as no high-quality genome sequencing data or associated annotations for this strain are available at present, it remains challenging to study the metabolic mechanisms underlying this phenotype. Herein, we report a 39,305,439 bp draft genome assembly for C. dermatis NICC30027 comprised of 37 scaffolds, with 60.15% GC content. Within this genome, we identified 524 tRNAs, 142 sRNAs, 53 miRNAs, 28 snRNAs, and eight rRNA clusters. Moreover, repeat sequences totaling 1,032,129 bp in length were identified (2.63% of the genome), as were 14,238 unigenes that were 1,789.35 bp in length on average (64.82% of the genome). The NCBI non-redundant protein sequences (NR) database was employed to successfully annotate 11,795 of these unigenes, while 3,621 and 11,902 were annotated with the Swiss-Prot and TrEMBL databases, respectively. Unigenes were additionally subjected to pathway enrichment analyses using the Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Cluster of Orthologous Groups of proteins (COG), Clusters of orthologous groups for eukaryotic complete genomes (KOG), and Non-supervised Orthologous Groups (eggNOG) databases. Together, these results provide a foundation for future studies aimed at clarifying the mechanistic basis for the ability of C. dermatis NICC30027 to simultaneously utilize glucose and xylose to synthesize lipids.

• Journal of Microbiology and Biotechnology
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• v.1 no.1
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• pp.75-78
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• 1991

The carotenoid biosynthesis of a red oleaginous yeast, Rhodotorula glutinis was significantly changed when the yeast was grown on different carbon substrates. The highest carotenoid production was obtained on culture medium containing glucose when the carbon to nitrogen ratio (C/N ratio) was adjusted to 25.7. Galactose stimulated the biosynthetic rate of torularhodin, a xanthophyll component of the yeast. With decreasing C/N ratio of the medium, significant changes of $\gamma$-carotene and torularhodin were observed such that increase in the torularhodin concentration was nearly equal to the decrease in $\gamma$-carotene. It was speculated that the nature of carbon substrate affected the metabolic rate of the cell, and accompanied by the different pattern of carotenoid accumulation in the cell.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1773-1777
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• 2017

The aim of this study was to examine the efficiency of Rhodosporidium toruloides as a new tool to evaluate the triglyceride (TG) reduction effects of anti-obesity candidate materials. Unfermented and fermented persimmon leaf hot water extracts (UFPLE and FPLE) were used as anti-obesity agents. The content of TG in R. toruloides treated with FPLE was less than those with UFPLE by about 11% (p < 0.05) relative to the control (R. toruloides incubated in YPD medium without the agents). Fat reduction in 3T3-L1 cells achieved by FPLE was about 13% higher than that achieved by UFPLE.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.397-400
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• 2018

Rhodosporidium toruloides, an oleaginous yeast, can be used as a fast and reliable evaluation tool to screen new natural lipid-lowering agents. Herein, we showed that triglyceride (TG) accumulation was inhibited by 42.6% in 0.1% red radish coral sprout extract (RRSE)-treated R. toruloides. We also evaluated the anti-obesity effect of the RRSE in a mouse model. The body weight gain of mice fed a high-fat diet (HFD) with 0.1% RRSE (HFD-RRSE) was significantly decreased by 60% compared with that mice fed the HFD alone after the 8-week experimental period. Body fat of the HFD-RRSE-fed group was dramatically reduced by 38.3% compared with that of the HFD-fed group.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.211-215
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• 1998

Preparative isolation of lipid granules from Fhodotorula glutinis, which has been studied for long time to produce edible lipids, was carried out by flotation method in Ficoll-Linear density gradient. When the isolated lipid granules were suspended in a series of solutions containing varying concentration of osmotic stabilizer (sorbitoal and mannitol) ranging from 0.8M to 0M, the lipid granules appeared to be disrupted at a concentration between 0.8M and 0.7, and again at a concentration below 0.1M, suggesting that lipid granules have a membraneous structure and that at least two types of lipid granules are present. Compositional analysis of lipids from lipid granules revealed that lipids are composed mainly of neutral lipids (87.8% of total lipids), predominantly as triacylglycerols (71.89%). Marked differences were observed inphospholipids between lipids of lipid granules and those of whole cells . The major components of phospholipids in lipid granules and inwhole cells are phosphatidylcholine(38.6%) and phosphatidylserine(42.8%), respectively. In addition, significant differences were also observed in the fatty acid composition of phospholipids. As phospholipids are important structural components of membranes, these differences lead to the suggesting that the membrane of lipid granules may be distinct functionally and structurally from other membranes of yeast cells. The major fatty acid components of neutral lipidss of whole cells and lipid granules are palmitic , oleic and linoleic acid. However , degreeof fatty acid unsaturation of neutal lipids of lipid granules was much lower than that of neutral lipids of whole cells.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.794-800
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• 1993

A lipid producing yeast was screened from leaves of Albabiscus and was identified as a Rhodotorula graminis SW 214. During the shakining incubation of 8 days at $25^{\circ}C$, the yeast produced extracellular lipids of 7.3g/l of the media. The relative concentration of carbon and nitrogen sources in the media influenced the extracellular lipid production greatly. When with nitrogen sources in the media were almost exhausted for growth of the yeast the sufficient carbon sources, the lipid production proceeded vigorously. Eight days of batch cultivation with 8% glucose, 2.5g/l of yeast extract, $KH_{2}PO_{4}(1g/l)\;MgSO_{4}\;(0.2g/l)$ and pH 6 gave maximum biomass and extracellular lipid production of 8.05g/l and 8.89g/l, respectively. The acid value, saponificatio value, the iodine value, ad the unsaponifiable matter of the extracellular lipids of Rhodotorula graminis SW 214 were 2.6, 534, 5.1 and 2.4, respectively. Lipid was constituted 75.2% triglyceride, 5.9% free fatty acid, 10.8% phospholipid, 4.9% esterified sterol and 3.3% free sterol. Major fatty acids found were 3-hydroxypentadecanoate, 3-hydroxyhexadecanate, trans-9-octadecanate, cis-9-hexadecanate (hydroxy palmitic), 15-methylhexadecanate (oleic), 18-methylno-nadecanate, octadecanate (stearic) and 3-hydroxytridecante.

• KSBB Journal
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• v.13 no.1
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• pp.65-70
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• 1998

The physiochemical properties of extracellular lipid produced by an oleaginous yeast, Rhodotorula glutinis K-501 were examined. From the analytical experiments, it was suggested that the extracellular lipid produced is glycolipidic compound. Critical micelle concentration and minimum surface tension of the extracellular lipid in aqueous solution were 89mg/L and 31dyne/cm, respectively. Surface tension was also constant throughout wide range of pH. The emulsifying abilities and dispersing power of the extracellular lipid were much greater than those of commercial surfactants such as Tween 80 and Triton X-100 by factors of 2-3 and 1.3, respectively.

• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.256-267
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• 2019

The use of low-cost substrates represents one key issue to make single cell oil production sustainable. Among low-input crops, Arundo donax L. is a perennial herbaceous rhizomatous grass containing both C5 and C6 carbohydrates. The scope of the present work was to investigate and optimize the production of lipids by the oleaginous yeast Cutaneotrichosporon curvatus from undetoxified lignocellulosic hydrolysates of steam-pretreated A. donax. The growth of C. curvatus was first optimized in synthetic media, similar in terms of sugar concentration to hydrolysates, by applying the response surface methodology (RSM) analysis. Then the bioconversion of undetoxified hydrolysates was investigated. A fed-batch process for the fermentation of A. donax hydrolysates was finally implemented in a 2-L bioreactor. Under optimized conditions, the total lipid content was 64% of the dry cell weight and the lipid yield was 63% of the theoretical. The fatty acid profile of C. curvatus triglycerides contained 27% palmitic acid, 33% oleic acid and 32% linoleic acid. These results proved the potential of lipid production from A. donax, which is particularly important for their consideration as substitutes for vegetable oils in many applications such as biodiesel or bioplastics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.2
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• pp.144-153
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• 2014

Both docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. Lipids in microbial cells play various biological roles and, consequently, much research has been carried out on their role in cell physiology. The lipid composition of microorganisms can exhibit considerable variations depending on environment. The effects of culture conditions, temperature (15, 20, 24, 28, 32 and $36^{\circ}C$), salinity (10, 20, 30, 40 and 50 psu), pH (pH5, 6, 7, 8 and 9), rotation speeds (50, 100, 150 and 200 rpm), carbon sources, nitrogen sources and C/N ratio on the production of docosahexaenoic acid, fatty-acid profiles, and acids secreted to the broth culture by the oleaginous microorganism, Schizochytrium mangrovei (KCTC 11117BP), were studied. Temperature (initially $28^{\circ}C$), salinity (20 psu), pH (pH7), rotation speeds (100 rpm), organism fatty acids, and secreted acids in the broth were varied during cultivation of S. mangrovei. At pH 7.0, S. mangrovei was able to accumulate lipids up to 40% of its biomass, with 13% (w/w) DHA content. The monosaccharides glucose and fructose, and yeast extract were suitable carbon and nitrogen sources, respectively. The primary omega-3 polyunsaturated fatty acid produced was docosahexaenoic acid.