• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.592-599
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• 2019

Ostrea denselamellosa and Eriocheir japonica samples were collected from the Seomjin River in 2019 as part of the "Research of Host-Associated Bacteria" research program. Almost 200 bacterial strains were isolated from the O. denselamellosa and E. japonica samples and subsequently identified by 16S rRNA gene sequencing. Among the bacterial isolates, ten strains possessed greater than 98.7% sequence similarity with published bacterial species that had not previously been recorded in Korea. These species were phylogenetically diverse, belonging to three phyla, four classes, seven orders, and eight genera. At the genus and class level, the previously unrecorded species belonged to Pseudoalteromonas, Aliivibrio, Rheinheimera, Leucothrix, and Shewanella of the class Gamma-proteobacteria, Olleya of the class Flavobacteriia, Algoriphagus of the class Cytophagia, and Lactococcus of the class Bacilli. The previously unrecorded species were further characterized by examining their Gram staining, colony and cell morphology, biochemical properties, and phylogenetic positions.

• Korean Journal of Plant Taxonomy
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• v.46 no.1
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• pp.55-59
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• 2016

Justicia kampotiana Benoist (Acanthaceae) is reported as a new record for the flora of Vietnam. This species differs from its allied species J. ingrata Benoist in having corolla outside pubescent, tubes slightly longer than limbs and considerably shorter petioles. Description, line drawing and color photographs are provided for species identification. Furthermore, a comparison of the diagnostic characters with those of related species is made.

• Journal of Species Research
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• v.9 no.1
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• pp.35-45
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• 2020

In 2016 and 2017, as part of a comprehensive investigation to identify the prokaryotic species in Korea, a total of 12 bacterial strains were isolated from the gastrointestinal tract and/or fecal samples of four endangered species, including reptile, bird, and marine and terrestrial mammals. Phylogenetic analysis with the 16S rRNA gene sequence was used to assign these strains to the phyla, Firmicutes, Actinobacteria or Proteobacteria. Furthermore, most of the strains Firmicutes belonged to the order Lactobacillales. Interestingly, 12 of the isolated strains have not been previously reported from the Korean Peninsula. Also, based on their high 16S rRNA gene sequence similarities(>98.7%) and formation of strong monophyletic clades with the closest type species, each isolated strain of isolates was assigned to an independent, predefined bacterial species. Gram-stain reaction, colony and cell morphology, biochemical characteristics, isolation source, and NIBR IDs are described in the species description section.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2355-2364
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• 2018

We evaluated the effect of particle size and associated dynamics on a hydrocyclone separation process in order to understand the movement of the particle trajectories inside the hydrocyclone via numerical analysis, with particles of acid hydrolysis residues discharged in $TiO_2$ production via the sulfate method as a case study. The values obtained from the numerical simulation were successfully compared with those from experimental tests in the literature, allowing a description of the dynamics of the particles, their acting forces, and their relevant properties together with separation efficiency. The results showed that particle motion is jointly controlled by the drag force, the pressure gradient force and the centrifugal force. With increasing particle size, the influence of the drag force is weakened, whereas that of the centrifugal force and pressure gradient is strengthened. Factors including particle density, slurry viscosity, and inlet slurry flow rate also contribute to a clear and useful understanding of particle motion behavior in the hydrocyclone as a method for improving the separation efficiency.

• Journal of Species Research
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• v.11 no.3
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• pp.143-154
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• 2022

To obtain unrecorded bacterial species in Korea, various marine samples were collected from Jeollanam-do Province, Korea in 2021. After plating the samples on marine agar and marine R2A agar, and incubating aerobically and anaerobically, approximately 1200 bacterial strains were isolated and identified using 16S rRNA gene sequences. A total of 30 strains showed ≥98.7% 16S rRNA gene sequence similarity with validly published bacterial species but not reported in Korea, indicating that they are unrecorded bacterial species in Korea. The unrecorded bacterial strains belonged to 4 phyla, 7 classes, 13 orders, 19 families, and 22 genera, which were assigned to Azospirllium, Loktanella, and Pseudovibrio of the class Alphaproteobacteria; Grimontia, Halomonas, Marinobacter, Microbulbifer, Photobacterium, Pseudoalteromonas, Pseudidiomarina, Ferrimonas, Shewanella, Simiduia, Thalassotalea, and Vibrio of the class Gammaproteobacteria; Priestia and Enterococcus of the class Bacilli; Persicobacter of the class Cytophagia; Aureivirga of the class Flavobacteriia; Propionigenium and Psychrilyobacter of the class Fusobacteriia; and Tepidibacter of the class Clostridia. The details of the unreported species including Gram reaction, colony and cell morphology, biochemical characteristics, and phylogenetic position are also provided in the description of the strains.

• Journal of Species Research
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• v.1 no.2
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• pp.232-239
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• 2012

Taxonomy of umbelliferous taxa Heracleum moellendorffii complex has been unclear in their species delimitation in the far-eastern Asian regions. In both Korea and China Heracleum moellendorffii was adopted for their description while H. sphondylium was chosen to describe Japanese Heracleum. From Genbank accessions, taxa collected from Kamtchatka and Promorskiy, Russia were defined as H. maximum, endemic taxon to North America. In this study, we reviewed the taxonomy of Heracleum moellendorffii complex in Korea and neighboring countries on the basis of molecular phylogenies derived from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) regions. From three Korean accessions of Heracleum investigated in this study, two types of ITS sequences were obtained; two accessions were related to Chinese H. moellendorffii var. moellendorffii and North American H. maximum without forming a clade while the other one was identical to accession from H. maximum from Primorskiy, Russia. In the other hand, Japanese H. moellendorffii (=H. sphondylium ssp. sphondylium var. nipponicum in the flora of Japan) was closely related to H. maximum accessions from Korea and Russia, not nested within the clade comprising several subspecies of H. sphondylium. In order to delimit species boundaries among putatively closely related Heracleum species in fareastern Asian countries, more samples and much more rapidly evolved DNA regions must be investigated with interpretation of morphological and anatomical features.

• Journal of Species Research
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• v.5 no.3
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• pp.539-540
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• 2016

Microturbellarians, small free-living Platyhelminthes are rich in freshwater environments. They are useful as indicator of water quality. There has never been a record of microturbellarians in Korea. Here I report a microturbellarian species, Catenula confusa Nuttycombe, 1956. Although specimens in this study show some differences with those of the original description of C. confusa in length and width of zooid, they conform to the specific diagnosis of this species.

• Journal of Species Research
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• v.5 no.3
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• pp.355-358
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• 2016

A spionid polychaete, Scolelepis (Scolelepis) kudenovi Hartmann-Schroder, 1981, is newly reported from Korean waters with description and illustration. Scolelepis (Scolelepis) kudenovi is characterized by a combination of the following morphological features: the notopodial setae are present on the setiger 1; the occipital tentacle is absent; the branchiae are partially fused to the notopodial postsetal lamellae; the notopodial and neuropodial hooded hooks are bidentate only; the notopodial hooded hooks are present on the posterior setigers. A key to Scolelepis species from Korean waters is provided in this paper.

• Journal of Species Research
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• v.5 no.3
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• pp.468-476
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• 2016

We firstly report three stichotrichs, Metaurostylopsis cheni Chen, Huang & Song, 2010, Gonostomum strenuum (Engelmann, 1862) Sterki, 1878, and Lamtostyla granulifera Foissner, 1997, collected in South Korea. We investigated these ciliates based on observations of live and protargol-impregnated specimens.

• Journal of Forest and Environmental Science
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• v.31 no.1
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• pp.63-67
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• 2015

Two newly recorded spiders, Cheiracanthium lascivum Karsch, 1879 of Eutichuridae and Gnaphosa kamurai Ovtsharenko, Platnick and Song, 1992 of Gnaphosidae are described and illustrated from Korea.