• Journal of Microbiology
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• v.44 no.4
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• pp.432-438
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• 2006

Twelve actinomycete strains were isolated from Egyptian soil. The isolated actinomycete strains were then screened with regard to their potential to generate antibiotics. The most potent of the producer strains was selected and identified. The cultural and physiological characteristics of the strain identified. the strain as a member of the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene (1.5kb) of the most potent strain evidenced a 99% similarity with Streptomyces spp. and S. aureofaciens 16S rRNA genes, and the isolated strain was ultimately identified as Streptomyces sp. MAR01. The extraction of the fermentation broth of this strain resulted in the isolation of one major compound, which was active in vitro against gram-positive, gram-negative representatives and Candida albicans. The chemical structure of this bioactive compound was elucidated based on the spectroscopic data obtained from the application of MS, IR, UV, $^1H$ NMR, $^{13}C$ NMR, and elemental analysis techniques. Via comparison to the reference data in the relevant literature and in the database search, this antibiotic, which had a molecular formula of $C_{19}H_{29}NO_2$ and a molecular weight of 303.44, was determined to differ from those produced by this genus as well as the available known antibiotics. Therefore, this antibiotic was designated Meroparamycin.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1473-1483
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• 2014

Reports of herbicide resistance events are proliferating worldwide, leading to new cultivation strategies using combinations of pre-emergence and post-emergence herbicides. We analyzed the impact during a one-year cultivation cycle of several herbicide combinations on the rhizobacterial community of glyphosate-tolerant Bt-maize and compared them to those of the untreated or glyphosate-treated soils. Samples were analyzed using pyrosequencing of the V6 hypervariable region of the 16S rRNA gene. The sequences obtained were subjected to taxonomic, taxonomy-independent, and phylogeny-based diversity studies, followed by a statistical analysis using principal components analysis and hierarchical clustering with jackknife statistical validation. The resilience of the microbial communities was analyzed by comparing their relative composition at the end of the cultivation cycle. The bacterial communites from soil subjected to a combined treatment with mesotrione plus s-metolachlor followed by glyphosate were not statistically different from those treated with glyphosate or the untreated ones. The use of acetochlor plus terbuthylazine followed by glyphosate, and the use of aclonifen plus isoxaflutole followed by mesotrione clearly affected the resilience of their corresponding bacterial communities. The treatment with pethoxamid followed by glyphosate resulted in an intermediate effect. The use of glyphosate alone seems to be the less aggressive one for bacterial communities. Should a combined treatment be needed, the combination of mesotrione and s-metolachlor shows the next best final resilience. Our results show the relevance of comparative rhizobacterial community studies when novel combined herbicide treatments are deemed necessary to control weed growth.

• Korean Journal of Plant Taxonomy
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• v.39 no.4
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• pp.304-308
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• 2009

One new naturalized species was recorded from Jeollanam-do Yeongam-gun, Daegu, and Daejeon in Korea. Hedyotis corymbosa grows well where there is enough sunlight; in moist, sandy soil. Hedyotis corymbosa (Rubiaceae) can be distinguished from other species in the same genus by longer peduncles, and a lot of flowers. We gave it the Korean name 'San-bang-back-un-pul' based on the specific epithet 'corymbosa'.

• Mycobiology
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• v.46 no.4
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• pp.297-304
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• 2018

Two new records of Trichocomaceae, namely Aspergillus allahabadii and Penicillium sizovae, were isolated in 2016 during a survey of fungal diversity in different crop fields locations in Gyeongnam, Korea. These species were identified based on morphological characters and phylogenetic analysis using internal transcribed spacer region and ${\beta}-tubulin$-encoding gene sequence data. A. allahabadii and P. sizovae have not yet been reported in Korea. Thus, this is the first report of these species in Korea, and their descriptions as well as details of their morphological characters are presented.

• Journal of Species Research
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• v.10 no.1
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• pp.12-22
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• 2021

During a comprehensive investigation of indigenous prokaryotic species in Korea, 25 and 10 bacterial strains assigned to the classes Alphaproteobacteria and Betaproteobacteria, respectively, were isolated from diverse environmental habitats, including soil, mud, tidal field, sea water, sand, rusted iron, and leaf. Based on their high 16S rRNA gene sequence similarities (>98.7%) and the formation of robust phylogenetic clades with type species, each strain was assigned to an independent and predefined bacterial species. Since there were no published or official reports regarding these 35 isolates in Korea, they - 25 species of 14 families in the 5 orders of Alphaproteobacteria and 10 species of 3 families in the two orders of Betaproteobacteria - have been reported as unrecorded species in Korea. In addition, Gram reaction, colony and cell morphology, basic biochemical characteristic, isolation source, and strain ID of each species are also described in the species description sections.

• Korean Journal of Plant Taxonomy
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• v.51 no.4
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• pp.345-352
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• 2021

Diarthron linifolium Turcz. is an annual herb usually found in sandy soil or limestone areas. Plants in the genus Diarthron are known to have toxic chemicals that may, however, be potentially useful as an anticancer treatment. Diarthron linifolium is a unique species among the species of the genus distributed in Korea. Here, we determine the genetic variation of D. linifolium collected in Korea with a full chloroplast genome and investigate its evolutionary status by means of a phylogenetic analysis. The chloroplast genome of Korean D. linifolium has a total length of 172,644 bp with four subregions; 86,158 bp of large single copy and 2,858 bp of small single copy (SSC) regions are separated by 41,814 bp of inverted repeat (IR) regions. We found that the SSC region of D. linifolium is considerably short but that IRs are relatively long in comparison with other chloroplast genomes. Various simple sequence repeats were identified, and our nucleotide diversity analysis suggested potential marker regions near ndhF. The phylogenetic analysis indicated that D. linifolium from Korea is a sister to the group of Daphne species.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.319-329
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• 2022

In July 2020, wilting symptoms were observed among adzuki bean plants (Vigna angularis var. angularis L.) in the fields in Yeosu, Korea. Infected plants showed yellowing of leaves, browning inside the stems, splitting of stem bark, and wilting. When these plants were uprooted, their roots were found to be brown. The fungal pathogens NC20-737, NC20-738, and NC20-739 were isolated from symptomatic stem and root tissues. These pathogens were identified as a Fusarium fujikuroi species complex based on their morphological characteristics. Molecular identification was performed using the DNA sequence of translation elongation factor 1 alpha and the RNA polymerase II second largest subunit regions. The nucleotide sequences of all three isolates were similar to the F. fujikuroi reference isolates NRRL 13566 and NRRL 5538 of the National Centre for Biotechnology Information GenBank. A pathogenicity test was conducted by the soil inoculation method with cornmeal sand inoculum. Approximately 3 weeks after inoculation, symptoms were observed only in the inoculated adzuki bean seedlings. To the best of our knowledge, this is the first report of Fusarium root rot caused by F. fujikuroi in adzuki beans, both in Korea and worldwide.

• Journal of Species Research
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• v.12 no.2
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• pp.174-179
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• 2023

Three newly recorded rotifers were collected through surveys of several islands in Korea: Lecane perplexa (Ahlstrom, 1938); Lindia torulosa Dujardin, 1841; and Monommata maculata Harring & Myers, 1930. These species represent 24th, second, and third records of each genus discovered in Korea, respectively. Lecane perplexa and Monommata maculata, were collected from reservoirs using plankton nets, whereas Lindia torulosa was collected from a soil sample. The morphological characteristics of the discovered species are as follows: Lecane perplexa is characterized by a straight or slightly concave anterior margin of the lorica, an incomplete transverse fold on the ventral lorica, and a single toe with pseudoclaws and accessory claws; Lindia torulosa has an illoricated and vermiform body, a head with rostrum, a pair of auricles, cardate type trophi, and distinctively shaped epipharynx components; and Monommata maculata is characterized by long toes, an inner margin of rami with 10-12 serrated teeth, 3-4 large teeth, and interlocking teeth. Here, the morphological characteristics of the three Korean monogonont rotifers, which include trophi photographs, are presented. In addition, partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) of each species are presented.

• Journal of Species Research
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• v.12 no.spc2
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• pp.15-22
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• 2023

During a comprehensive investigation of indigenous prokaryotic species in Korea, 20 and one bacterial strains assigned to the phyla Bacillota and Verrucomicrobiota, respectively, were isolated from diverse environmental habitats, including soil, mud, tidal flat, seawater, sand, sediment, brackish water, and healthy human urine. Based on their high 16S rRNA gene sequence similarities (>98.7%) and the formation of robust phylogenetic clades with their closest related reported species, each strain was assigned to an independent and predefined bacterial species. Since there were no published or official reports regarding these 21 isolates in Korea, they - 20 species of four families in two orders of the phylum Bacillota and one species of the phylum Verrucomicrobiota - have been reported as unrecorded species in Korea. In addition, Gram staining, colony and cell morphology, basic biochemical characteristic, isolation source, and strain ID of each species are also described in the species description sections.

• Mycobiology
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• v.51 no.4
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• pp.216-229
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• 2023

Acarosporaceae is a crustose lichen and is known as a species that has more than 50 multispores, and has hyaline spores. Those taxa are often found in rock and soil in mountain areas or coastal regions in Korea, and very diverse forms and species are known. However, after an overall genetic phylogenetic analysis of carbonized ascomata in 2015, species consisting only of the morphological base are newly divided, and several species of Acarosporaceae in Korea are also being discovered in this situation. As a result of analysis using internal transcribed spacer (ITS) and nuLSU gene analysis, Korean species belonged to Acarospora and Sarcogyne clade, and Acarospora classified as the Acarospora clade was mixed with the Polysporina group and the Sarcogyne clade is mixed with the Acarospora. We identified two new species (Acarospora beangnokdamensis J. S. Park & S. O. Oh, sp. nov., Sarcogyne jejuensis J. S. Park & S. O. Oh, sp. nov.) through morphological, molecular, and secondary metabolite substance and found one new record (Sarcogyne oceanica K. Knudsen & Kocourk). We have made a classification key for Acarospora and Sarcogyne in Korea and reported all information together here.