• Journal of Life Science
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• v.11 no.2
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• pp.133-137
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• 2001

The molecular taxonomic relationship of nine species in the genus Moniliella Stolk & Dakin and Trichosporonoides Haskins & Spencer and six species of other yea나-like fungi was examined by sequencing analysis of large subunit rDNA D1/D2 variable domain. The fifteeen species fell into two major groups corresponding with their genetic relationships. The nine species of the genus Moniliella and Trichosporonoides were placed at the same cluster. similarity values based on the D1/D2 domain sequences were 45.4-100% among species of genus Moniliella, 45.2-84.4% among genus Trichosporonoides species, and 45.6-90.1% among species of genus Moniliella and Trichosporonoides. Identical sequence similarity was observed between M. suaveolens var. nigra and M. suaveolens. A colse relationship of M. mellis. and M. acetoabutens is observed. The result of this study provided and insight into the genetic origins of genus Moniliella and Trichosporonoides species as well as their genetic relationships. Genus Moniliella and Trichosporonoides are closely related to each other based on sequence analysis of the large subunit rDNA D1/D2 region and we suggest combination of the genus Moniliella and Trichosporonoides to single genus.

• The Korean Journal of Ecology
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• v.18 no.1
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• pp.157-177
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• 1995

Monthly changes in communities of benthic macroinvertebrates collected in the Suyong and Soktae stream of the Suyong river were investigated from September 1993 to August 1994. The total number of species collected during the study period ranged from seven to seventy six species according to pollution levels at the study sites. Monthly changes in species richness appeared differently in different taxonomic assemblages. In chironomids differences in species richness responding to different levels of saprobity were shown consistently as time proceeded. In Ephemeroptera species richness at the relatively clean sites responded sensitively to slight enrichment. In connection with species richness the monthly changes in densities in taxonomic assemblages also appeared to effectively represent environmental impacts. Species diversity generally represented the pollution status also, however the monthly variations at the study sites appeared to be relatively high. The clustering analysis showed that the communities collected at polluted sites were grouped closely, and the communities collected at the relatively clean sites were clustered to the same stream although the degree of community association was low, Through the Principal Component Analysis, the impact of Pollution was reflected in a great degree in overall community variations.

• Korean Journal of Environment and Ecology
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• v.29 no.1
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• pp.69-80
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• 2015

Studies on Trapa of Korean, Japanese, and Chinese origins have been generally limited to currently living Trapa, thereby demonstrating the lack of phylogenetic approaches. In the present study, we conducted a numerical taxonomic study on 34 Korean origin Trapa species newly discovered in peat deposits. By using the numerical taxonomy as well as geological data, we created an appearance map based on the periods and taxonomic groups of the Korean Trapa. Further, by using this appearance map, we reviewed the limitations that exist in the taxa and simultaneously discussed the adaptational environment of Trapa in each period. Although other studies have discussed new variants of Trapa worldwide, including T. litwinowii V. vassil. var. chihuensis S.F.Guan & Q.Lang of China (Guan and Lang, 1987), the present study is significant because it provides data on the origin of Korean Trapa species. The availability of such data is essential in determining the adaptational environment of the presently living Trapa. To our knowledge, this is the first report of approximately 10 newly discovered and other presently living species of Trapa. Further, the appearance map in the present study allows the use of the 10 newly discovered species and variants of 34 Trapa species indigenous to South Korea for over 1000 years, for a comparison with the currently living Trapa species. Thus, the present study results could serve as important basic data to understand the adaptational environment of the genus Trapa. from the past to the present in Korea.

• Journal of Microbiology and Biotechnology
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• v.31 no.11
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• pp.1490-1500
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• 2021

Various microorganisms reside in the human vagina; the vaginal microbiome is closely linked to both vaginal and general health, and for this reason, microbiome studies of the vagina are an area of research. In this study, we analyzed the vaginal microbiome of women before and after menopause to further increase our understanding of the vaginal microbiome and its contribution to general health. We did a 16s rRNA gene-based metagenomic analysis on the vaginal fluids of 11 premenopausal and 19 postmenopausal women in Korea. We confirmed that the taxonomic composition was significantly different between the two groups. In postmenopausal women, species richness was significantly decreased, but species diversity was significantly increased. In particular, among the taxonomic components corresponding to all taxon ranks of the vaginal microbiome, a reduction in Lactobacillus taxa after menopause contributed the most to the difference between the two groups. In addition, we confirmed through metabolic analysis that the lactic-acid concentration was also decreased in the vaginal fluid of women after menopause. Our findings on the correlation between menopause and the microbiome could help diagnose menopause and enhance the prevention and treatment diseases related to menopause.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.47.1-47.1
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• 2020

Multi-band photometry provides an advantage in being able to perform taxonomic classification analysis on a large number of asteroids in a much shorter period of time than spectroscopy. We observed main-belt asteroids using Korea Microlensing Telescope Network (KMTNet) in CTIO during the summer seasons in the southern hemisphere, mostly in December 2015, 2016 and 2017 with two visible photometric systems, SDSS (g, r, i, and z), and Johnson-Cousins (B, V, R, and I). Targets were selected for the asteroids which had already been classified based on Bus-Binzel taxonomy (Bus & Binzel, 2002) and DeMeo taxonomy (DeMeo et al. 2009). Not only the targets but also numerous serendipitously observed asteroids were identified. In summary, 6817 and 5456 known objects, including 307 and 233 already classified asteroids were observed with SDSS and Johnson-Cousins systems, respectively. Using principal component analysis, the three major asteroid complexes and a class, S-, C-, and X-complexes and V class are found to be well separated in the principal component plane (spectral slope and 1 micron absorption depth) with both filter systems. We will present and discuss the results of our newly proposed three-dimensional color taxonomy for asteroids using the whole dataset (Roh et al., to be submitted).

• Korean Journal of Plant Taxonomy
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• v.48 no.3
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• pp.230-247
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• 2018

We conducted principal component analyses using the quantitative characteristics of the genus Sorbaria to investigate and explore morphological variation and diagnostic characteristics. The genus Sorbaria was divided into two groups based on erect or pendulous inflorescence, the existence of hairs on the ovary and follicle surfaces, the number of stamens, and the shape of the sepal. As a result of our investigation and of a morphometric analysis, these two groups could be also classified using quantitative characteristics, in this case the number of leaflets, the size of the leaflets, the width of the inflorescence, the size of the sepal, the petal, and the follicles and seeds. In the Sorbifolia group (S. grandiflora and S. sorbifolia complex), the size of lateral leaflets, number of veins, gland and stellate density on the abaxial surface of leaflets, and the petal and follicle size were found to be useful identification characteristics. The terminal and lateral leaflet size and the gland and stellate density on the abaxial surface of the leaflets were found to be characters of taxonomic value for the Kirilowii group (S. arborea complex, S. kirilowii, and S. tomentosa complex). The results of the numerical analysis conducted here can provide valuable information to those reconsidering and delimiting a taxonomic revision of the genus Sorbaria.

• Journal of Plant Biotechnology
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• v.38 no.1
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• pp.9-14
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• 2011

To determine whether pattern recognition based on metabolite fingerprinting for whole cell extracts can be used to discriminate cultivars metabolically, leaves of nine commercial Orostachys plants were subjected to Fourier transform infrared spectroscopy (FT-IR). FT-IR spectral data from leaves were analyzed by principal component analysis (PCA) and Partial least square discriminant analysis (PLS-DA). The dendrogram based on hierarchical clustering analysis of these PLS-DA data separated the nine Orostachys species into five major groups. The first group consisted of O. iwarenge 'Yimge', 'Jeju', 'Jeongsun' and O. margaritifolius 'Jinju' whereas in the second group, 'Sacheon' was clustered with 'Busan,' both of which belong to O. malacophylla species. However, 'Samchuk', belong to O. malacophylla was not clustered with the other O. malacophylla species. In addition, O. minuta and O. japonica were separated to the other Orostachys plants. Thus we suggested that the hierarchical dendrogram based on PLS-DA of FT-IR spectral data from leaves represented the most probable chemotaxonomical relationship between commercial Orostachys plants. Furthermore these metabolic discrimination systems could be applied for reestablishment of precise taxonomic classification of commercial Orostachys plants.

• Journal of Microbiology
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• v.38 no.3
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• pp.122-131
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• 2000

Phylogenetic classification of the Aphyllophorales was conducted based on the analysis of nuclear small subunit ribosomal RNA (nuc SSU rDNA) sequence. Based on phylogenetic groupings and taxonomic characters, 16 families were recognized and discussed. Although many of the characters had more or less homoplasies, miroscopic characters such ad the mitic system and clamp, spore amyloidity and rot type appeared to be important in the classification of the Aphyllophorales. Phylogenetically significant families were newly defined to improve the classification of the order Aphyllophorales.

• Journal of Life Science
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• v.11 no.1
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• pp.19-23
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• 2001

To develop the effective microbial screening method, pyrolysis mass spectrometry (PyMS) fingerprinting was evaluated as a tool that discriminate various yeast strains. The target yeast strains were isolated from industrial wastewater. Seventeen environmental isolated yeast strains were examined by pyrolysis mass spectrometry and sequencing analysis of the large subunit rRNA gene D1/D2 region. The PyMS results were compared with those of sequencing analysis. Taxonomic correlations were observed between the PyMS data and the sequencing results. It was concluded that PyMS provides a rapid, reliable and cost-reducing method for discrimination of the yeast strains.

• Korean Journal of Plant Taxonomy
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• v.43 no.1
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• pp.12-21
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• 2013

To clarify the taxonomic position for Astragalus nakaianus and provide correct scientific name for A. mongholicus cultivar in South Korea, we examined external morphological characters and sequence variations from ITS and five cp non-coding DNA regions. Genetic structure was also analyzed for 61 individuals from three populations using nine microsatellite loci. We found no significant difference between the South Korean cultivar and A. mongholicus var. dahuricus when morphology and ITS sequences were considered. Morphologically, A. nakaianus specimens varied somewhat from A. mongholicus var. mongholicus and var. dahuricus in habit, plant height, and lengths of leaf axis and leaflet. Although sequence data from ITS and cp noncoding DNA regions could not distinguished A. nakaianus from A. mongholicus, microsatellite analysis revealed strong structuring between the cultivar and A. nakaianus. Therefore, we conclude that the South Korean A. mongholicus cultivar should be treated as A. mongholicus var. dahuricus and that A. nakaianus should be merged into A. mongholicus as a variety, i.e., A. mongholicus var. nakaianus.