• Journal of Life Science
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• v.12 no.6
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• pp.765-768
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• 2002

Enantioselective hydrolysis of racemic styrene oxide by Rhodotorula sp. CL-82 was investigated. Reaction conditions including pH, temperature, and volume ratio of organic cosolvent were optimized using response surface methodology, and the optimal conditions of pH, temperature, and the volume ratio of cosolvent were determined to be 7.64, $33.26^{\circ}C$, and 3.09 %(v/v), respectively. Chiral (S)-phenyl oxirane could be obtained with high enantiomeric purity (ee ＞ 99%) and 20% yield (theoretical yield ＝ 50%) at the optimal rendition.

• Journal of the Korean Applied Science and Technology
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• v.40 no.5
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• pp.1126-1135
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• 2023

Nine microbial strains were isolated from the byproduct of ginseng processing and field of ginseng cultivation. Two strains among them were confirmed. Phylogenetic analysis of these 𝛽-Glucosidase strains confirmed that strain GYP-1 belongs to the Rhodotorula and strain GYP-3-3 belong to genus Brachybacterium. Rhodotorula sp. GYP-1 was finally selected due to its high biomass production. The 𝛽-Glucosidase activity of Rhodotorula sp. GPY-1 was assessed at 30 ℃, and Higher than 70% of the enzyme activity was maintained at the temperature range of 20-40℃. Although the optimum pH for the highest enzyme activity was pH 5.0, the enzyme was stable throughout the pH range of 5.0-8.0. In addition, Rhodotorula sp. demonstrated antifungal activity against the ginseng root rot disease caused by Botrytis.

• Korean Journal of Veterinary Research
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• v.22 no.2
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• pp.121-138
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• 1982

The present study was conducted in order to investigate the role of yeast-like fungi in bovine mastitis. Attempts were made to isolate and identify yeast-like fungi from the milk from normal udders and those with clinical or subclinical mastitis and from feces. Also incuded in the study were trials for the pathogenicity of the isolates for laboratory animals and efficacy of an anti-fungal drug for the treatment of mastitis. A total of 133 isolates of yeast-like fungi was made from milk and feces and they were identified as Candida (C.) albicans (5 isolates), C. krusei (63 isolates), C. tropicalis (27 isolates), Torulopsis (T.) glabrata (10 isolates), Rhodotourla sp. (6 isolates), Hansenula sp. (6 isolates) and Pichia sp. (1 isolate). Sixty seven strains of yeast-like fungi were isolated from the milk of 64 quarters (4.3% of quarters examined) of 55 cows (14.3% of cows examined). C. krusei, C. tropicalis, C. pseudotropicalis, C. parapsilosis and T. glabrata were isolated as the causative agents from 20 quarters (1.3% of quarters examined) with clinical mastitis. C. krusei, C. tropicalis, C. albicans, C. pseudotropicalis, T. glabrata, Rhodotorula sp. and Hansenula sp. were isolated as the causative agents from 22 quarters (1.5% quarters examined) with subclinical mastitis. C. tropicalis, C. krusei, T. glabrata and Rhodotorula sp. were isolated as the contaminants from 22 normal quarters (1.5% of quarters examined). C. krusei, C albicans, C. tropicalis, C. pseudotropicalis, C. parapsilosis, T. glabrata, Hansenula sp., Rhodotorula sp. and Pichia sp. were isolated as the contaminants from feces and all of the species except Pichia sp. were isolated from milk of the same cows at the some time. Intramammary infusion of nystatin was effective for the treatment of mastitis caused by C. albicans, C. krusei, C. tropicalis, C. pseudotoropicalis, C. parapsilosis, T. glabrata and Rhodotorula sp. C. albicans, C. krusei, C. tropicalis, C. pseudotropicalis, T. glabrata, Hamsenula sp. and Pichia sp. were pathogenic for rat but C. parapsilosis and Rhodotorula sp. were not.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.185-190
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• 1996

Some microorganisms including yeasts produce surface tension-decreasing biosurfactants. The strain G-1, the best producer of biosurfatants was isolated from the soil and identified as Rhodotorula sp., which was not discribed any report. The Rhodotorula sp. G-1 produced biosurfactant from vegetable oils, but failed to produce it from n-alkane or carbohydrate. Yeast extract was found to be more effective for the biosurfactant production as nitrogen source than any other inorganic nitrogen source. The composion of the optimal medium contained the following conponents: soybean oil 4%, glucose 2%, yeast extract 0.5%, KH$^{2}$PO$^{4}$ 0.1%, K$^{2}$HP0$^{4}$ 0.l%, MgSO$^{4}$ 5%, CaCl$^{2}$ 0.01%, NaCl 0.01%, pH 6.0. The surface tension activity was increased to 14% when, at first, the culture broth was fermented with only soybean oil as carbon sourse, and after 90 hours, feeded glucose, than that Of glucose and soybean oil added to it simultaneously. The maxium yield of the biosurfactant was about 15 g/l by after 90 hours, the feeding method of glucose.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.30-30
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• 2014

We isolated various yeasts from wild flowers in main islands, Jejudo, Ulleungdo and Yokjido of Korea and their yeasts were identified by comparison of their PCR-amplified D1/D2 regions of 26S rDNA using the BLAST database. Thirty two yeast strains of fourteen species were isolated from wild flowers of Jejudo. Forty eight yeast strains of twenty two species were isolated and identified from wild flowers of Ulleungdo, Korea. Sixty yeast strains belonged to twenty five species were isolated identified from wild flowers of Yokjido in Tongyeong, Korea. Only Metschnikowia reukaufii was overlapped from the three different islands areas. Two species overlapped from Jejudo and Ulleungdo: Pichia guilliermondii, Metschnikowia reukaufii. Seven species were overlapped from Ulleungdo and Yokjido: Cryptococcus albidus, Cryptococcus laurentii, Metschnikowia reukafii, Pichia scolyti, Rhodotorula glutinis, Rhodotorula graminis and Rhodotorula mucilaginosa. Four species were overlapped from Jejudo and Yokjido: Candida sp. Cryptococcus aureus, Metschnikowia reukafii and Pseudozyma sp.

• Microbiology and Biotechnology Letters
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• v.12 no.4
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• pp.271-276
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• 1984

Effect of C/N ratios on the cell growth, cell lipid, cell protein and fatty acids of Rhodotorula sp. was examined. At low concentration of nitrogen in cultural medium the growth of the yeast was retarded, whereas its growth was favorable at high concentration but lipid yield was decreased due to a high content of cell protein. In order to increase lipid yield, the optimum C/N ratio obtained was 45-50 (5% glucose, 0.0414% nitrogen). During the cultivation cell protein synthesis occurred mainly in initia stage and the lipid was accumulated rapidly at the late phase. The highest content of total fatty acid was observed at the optimum C/N ratio. The higher C/N ratio was the more unsaturation degree of fatty acid decreased. It was attributed principally to a decreased oleic acid with palmitic acid increased. No significant changes occurred in content of other fatty acids.

• Journal of the Korean Chemical Society
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• v.21 no.6
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• pp.449-452
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• 1977

The effect of carbon number of hydrocarbon used as a carbon source in the production of cellular lipid of Rhodotorula sp. and its fatty acid composition were investigated. Using Rhodotorula sp. on n-tetradecane and n-hexadecane whose carbon numbers are even, fermentation was carried out in a jar fermentor of 2 liter-capacity at $28^{\circ}C$, with pH range of 4.0∼4.6 and at oxygen flowing rate of 0. 4 vvm and agitation velocity of 1000 rpm. Drying the produced cell after completion of fermentation, cellular lipid was extracted from the cell using soxhlet extractor and examined its fatty acid composition by gas-liquid chromatography. Cellular lipid content in the cell produced on n-tetradecane and n-hexadecane were 12.0 % and 25,8 % on the basis of dry cell weight, respectively and their fatty acids were mostly even numbered in carbon number.

• The Korean Journal of Mycology
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• v.19 no.1
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• pp.41-46
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• 1991

Three isolates of yeast utilizing phthalic compounds as a sole carbon source were obtained from the surface waters exposed to the industrial effluents near Cheong Ju city. On the basis of microscopic observations on morphology and various biochemical characterizations, the three isolates were identifed as a species of Rhodotorula. Candida or Torulopsis. A number of aroma­tic chemicals including phthalic compounds would support the growth of these yeasts as a sole carbon source, Thus, the yeast isolates would have potentials in reduction of environmental burden due to industrial wastes of aromatic hydrocarbons.

• Mycobiology
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• v.51 no.6
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• pp.379-387
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• 2023

In this study, twenty-five yeast strains were isolated from soil samples collected in the gold mining ore in Gia Lai, Vietnam. Among them, one isolate named GL1^T could highly tolerate Cu²⁺ up to 10 mM, and the isolates could also grow in a wide range of pH (3-7), and temperature (10-40 ℃). Dried biomass of GL1 was able to remove Cu²⁺ effectively up to 90.49% with a maximal biosorption capacity of 18.1 mg/g at pH 6, temperature 30 ℃, and incubation time 60 min. Sequence analysis of rDNA indicated this strain was closely related to Rhodotorula mucilaginosa but with 1.53 and 3.46% nucleotide differences in the D1/D2 domain of the 28S rRNA gene and the ITS1-5.8S rRNA gene-ITS2 region sequence, respectively. Based on phylogenetic tree analysis and the biochemical characteristics, the strain appears to be a novel Rhodotorula species, and the name Rhodotorula aurum sp. nov. is proposed. This study provides us with more information about heavy metal-tolerant yeasts and it may produce a new tool for environmental control and metal recovery operations.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.4
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• pp.84-89
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• 2011

Cellulose-degrading bacteria were isolated and identified from cocopeat which has a good quality as a bulking agent in composting. Various bacteria from different sourecs of cocopeat were detected on CMC agar media, and these were found to be Burkholderi2a sp., Bacillu subtilis, Sphingomonas sp., Rhodotorula sp. & Pseudomonas sp. etc. Among these, four bacteria were further selected and analyzed for their biochemical characteristics and CMCase activities. CMCase activities of four bacteria, P. aeruginosa, P. stutzeri, B. subtilis, and P. luteola were found to be 83%, 40%, 8%, 6%, respectively, compared with that of the standard strain Cellulomonas sp.