• Journal of Microbiology
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• v.44 no.6
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• pp.674-679
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• 2006

Biodiversity of yeasts was investigated in the ginseng cultivation field. Among 34 isolates tested in this study, 26 isolates belonged to the hymenomycetous yeast group. These 26 strains were classified into 12 species including four new-species candidates that did not have clear affiliation to any established species. Seven isolates among the remaining strains were classified into three ascomycetous yeast species, and one isolate was identified as a urediniomycetous yeast species.

• Mycobiology
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• v.49 no.5
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• pp.521-526
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• 2021

Three isolates belonging to the ascomycetous genus Zygotorulaspora were obtained from the fruits of Cornus officinalis and Smilax china, and flowers of Dendranthema zawadskii var. latilobum in Gongju-si, Korea. Phylogenetic Analyses of the LSU D1/D2 domain and ITS region sequences supported the recognition of two new species: Zygotorulaspora cornina sp. nov. (type strain NIBRFGC000500475 = KACC93346P^PP) and Zygotorulaspora smilacis sp. nov. (type strain NIBRFGC000500476 = KACC93347P^PP). The two novel species revealed no growth on D-Galactose, unlike the other six species in the genus Zygotorulaspora. They are distinguished from each other by their phylogenetic differences and phenotypic characteristics such as assimilation of xylitol, 5-keto-D-gluconate, and ethanol. All species in the genus Zygotorulaspora including the two novel species have phenotypic traits of genus Zygotorulaspora: asci are persistent, sucrose and raffinose are assimilated, and m-inositol is not required for growth, and they are mainly associated with plants.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.361-371
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• 2023

The study was undertaken to isolate and characterize wild yeast strains from soil samples collected in Seoul, Korea. Among the 19 yeast strains obtained, 17 were previously recorded species. The remaining two strains, Wickerhamomyces sp. GW1-4 and Archaeorhizomyces sp. YB4-103 were new species candidates. The genomic and microbiological characteristics of GW1-4 and YB4-103 were investigated. Phylogenetic analyses based on the 26S rRNA gene sequences and internal transcribed sequences, GW1-4 and YB4-103, represent a distinct lineage within the family Phaffomycetaceae and Archaeorhizomycetaceae, respectively. The GW1-4 and YB4-103 strains had the highest sequence homology with Wickerhamomyces xylosivorus NBRC 111553^T (88.97%) and Archaeorhizomyces finlayi CBS 128710^T (87.55%), respectively.

• Journal of Microbiology and Biotechnology
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• v.33 no.8
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• pp.1023-1029
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• 2023

Biosurfactants reduce surface and interfacial tension due to their amphiphilic properties and are an eco-friendly alternative for chemical surfactants. In this study, a new yeast strain JAF-11 that produces a biosurfactant was selected using drop collapse method, and the properties of the extracts were investigated. The nucleotide sequences of the strain were compared with closely related strains and identified based on the D1/D2 domain of the large subunit ribosomal DNA (LSU) and internal transcribed spacer (ITS) regions. Neodothiora populina CPC 39399^T, the closest species with strain JAF-11, showed a sequence similarity of 97.75% for LSU and 94.27% for ITS, respectively. The result suggests that the strain JAF-11 represents a distinct species that cannot be assigned to any existing genus or species in the family Dothideaceae. Strain JAF-11 produced a biosurfactant reducing the surface tension of water from 72 mN/m to 34.5 mN/m on the sixth day of culture and the result of measuring the critical micelle concentration (CMC) by extracting the crude biosurfactant was found to be 24 mg/l. The molecular weight 502 of the purified biosurfactant was confirmed by measuring the fast atom bombardment mass spectrum. The chemical structure was analyzed by measuring ¹H nuclear magnetic resonance (NMR), ¹³C NMR, and two-dimensional NMRs of the compound. The molecular formula was C₂₆H₄₆O₉, and it was composed of one octanoyl group and two hexanoyl groups to myo-inositol moiety. The new biosurfactant is the first report of a compound produced by a new yeast strain, JAF-11.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.789-799
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• 1998

Literatures on microorganisms of traditional Korean nuruk published since 1945 were reviewed in this paper. Traditional Korean nuruk consists of raw barley and various grains. Traditional Korean nuruk consists of unbolied raw barely and various grains. They are ground to paste and moistened, and then naturally inoculated by airborne microorganisms. Therefore, many kinds of microorganisms such as fungi, yeast, and bacteria grwo in nuruk. Since 1945, new 14 species of Aspergillus and 9 species of Penicillium have been identified from traditional Korean nuruk. Total number of fungal species identified so far is now up to 38 species among 12 different genus. Among newly isolated fungal species, Aspergillus penicilloides and Penicillium, expansum showed not only high production rate of acid and amylase but also extreme stability of the enzyme at room temperature for 3 months. As examples of newly isolated yeast species, there are 5 species of Candida, 4 species of Hansenula, 1 species of Pichia and 1 species of Schizosaccharomyces. Total number of yeast species isolated so far is up to 18 species from different 8 genus. Newly isolated bacteria, were Bacillus pumilus, Lactobacillus casei and Leuconostoc mesenteroides.

• Mycobiology
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• v.43 no.4
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• pp.402-407
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• 2015

Two new fungal species of the genus Talaromyces, Talaromyces purpurogenus and Talaromyces trachyspermus from the Trichocomaceae family, were recovered during an investigation of fungal communities in soil collected from the Gangwon-do and Jeollanam-do provinces of Korea. These two species have not been previously officially reported from Korea. In this study, detailed descriptions of internal transcribed spacer rDNA and beta-tubulin gene regions of these two fungi are presented. Morphological features of the two fungi in five agar media, potato dextrose, oatmeal, malt extract, czapek yeast extract, and yeast extract sucrose, are also reported. The species were identified on the basis of molecular and morphological analysis, and herein we present data with detailed descriptions and figures.

• Journal of Microbiology
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• v.40 no.1
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• pp.55-62
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• 2002

Biodiversity af yeasts in various natural environments including soils, swamps and plants was investigated. By molecular identification methods based on the partial sequences of 265 rDNA, 69 isolates were assigned to 44 taxa including 27 known species. The remaining 17 taxa could potentially form new species. All of them were classified into Ascomycota, Hymenomycetes, Urediniomycetes and Ustilaginomycetes. Ascomycetous and ustilaginomycetous yeasts were generally isolated from flower samples, and hymenomycetous and urediniomycetous yeasts were generally isolated from soil samples. Distribution of yeast groups exhibited geographical variation. Yeast biodiversity of root sail also varied according to the associated plant species.

• Mycobiology
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• v.45 no.4
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• pp.327-337
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• 2017

Three new records of Ascomycota species (Chaetomium acropullum, Phialemonium globosum, Phialemonium atrogriseum) from field soils in Korea are presented in this study. These newly discovered fungal isolates were isolated from field soils from various places across Gyeongnam, Korea in 2016. All the isolates were identified and described based on morphological characteristics, and rDNA internal transcribed spacer and ${\beta}$-tubulin gene sequence data. Morphological features of these fungal species were studied on different agar media: potato dextrose agar, oatmeal agar, malt extract agar, Czapek yeast extract agar, and yeast extract sucrose agar. Full description and illustrations of their morphological characters are provided. These fungal species have not officially been previously reported in Korea.

• Journal of Microbiology and Biotechnology
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• v.33 no.10
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• pp.1329-1336
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• 2023

Microbial fermentation is often used to improve the functionality of plant-based food materials. Herein, we investigated changes in the physicochemical and functional properties of cabbage during yeast fermentation to develop new products using fermented cabbage. Among the 8 types of food-grade yeast, both Saccharomyces cerevisiae and Saccharomyces boulardii fermented 10% cabbage powder solution (w/w) the most effectively, leaving no soluble sugars after 12 h of fermentation. In addition, the yeast fermentation of cabbage resulted in functionally positive outcomes in terms of sulforaphane content, antioxidant properties, and anti-inflammatory activity. Specifically, the yeast-fermented cabbages contained about 500% more sulforaphane. The soluble fraction (5 ㎍/ml) of yeast-fermented cabbage had no cytotoxicity in murine RAW 264.7 cells, and the radical-scavenging capacity was equivalent to 1 ㎍/ml of ascorbic acid. Moreover, cabbage fermented with S. boulardii significantly suppressed both lipopolysaccharides (LPS)-induced nitric oxide production and LPS-induced reactive oxygen species production in RAW 264.7 cells, suggesting a potential anti-inflammatory effect. These results support the idea that yeast fermentation is promising for developing functionally improved cabbage products.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.108.2-108
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• 2000

No Abstract, See Full Text