• Journal of Environmental Science International
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• v.27 no.9
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• pp.771-780
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• 2018

To develope a microbial weed control agent, HCN-producing bacteria were isolated, and their characteristics were investigated. A selected strain of WA15 was identified as Pseudomonas koreensis by morphological, cultural, biochemical and 16S rRNA gene analyses. The conditions for HCN production was investigated by a One-Variable-at-a-Time (OVT) method. The optimal HCN production conditions were tryptone 1%, glycine 0.06%, NaCl 1%, and an initial pH and temperature of 5.0 and $30^{\circ}C$, respectively. The major component for HCN production was glycine. Under optimal conditions, HCN production was about 3 times higher than that of the basal medium. The WA15 strain had physiological activities, such as indoleacetic acid that was associated with the elongation of plant roots and siderophore and ammonification inhibiting fungal growth, and produced hydrolytic enzymes, such as cellulase, pectinase and lipase. The strain was able to inhibit the growth of phytopathogenic fungi, such as Rhizoctonia solani, Botrytis cinerea and Fusarium oxysporum, by the synergistic action of volatile HCN and diffusible antimicrobial compounds. A microscopic observation of R. solani that was teated with the WA15 strain showed morphological abnormalities of fungal mycelia, which could explain the role of the antimicrobial metabolites that were produced by the WA15 strain. The volatile HCN produced by the WA15 strain was also found to have insecticidal activity against termites. Our results indicate that Pseudomonas koreensis WA15 can be applied as a microbial agent for weed control and also as a termite repellent. Furthermore, it could be applied as a microbial termiticidal agent to replace synthetic insecticides.

• Journal of Wetlands Research
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• v.9 no.2
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• pp.33-43
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• 2007

Distribution area, actual vegetation map, standing crop biomass, relative growth, and primary productivity of Salix spp.were investigated to provide the basic data necessary for conservation and ecotechnological application of Salix community in the Upo wetland, Changryeong County, Gyeongsangnamdo Province, Korea from April 2005 to April 2006. 1. Among seven Salix species, the dominant species was S. nipponica and S. glandulosa was subdominant. There were six kinds of Salix communities such as S. nipponica, S. glandulosa, S. koreensis, S. nipponica-S. glandulosa, S. glandulosa-S. nipponica, and S. nipponica-S. koreensis. 2. Distribution area of S. nipponica community was largest as 28.46 ha among Salix communities and those of S. nipponica-S. glandulosa community, S. glandulosa-S. nipponica community, S. nipponica-S. koreensis community, S. glandulosa community, and S. koreensis community were 6.12 ha, 6.12 ha, 2.92 ha, 1.86 ha, and 0.81 ha, respectively. 3. The tree age, tree height, and DBH of S. nipponica were 5~13year, 4.1~7.2 m, and 3.0~14.0 cm and those of S. glandulosa were 2~36year, 3.5~10.1 m, and 3.2~26.0 cm, respectively. 4. The standing crop of S. nipponica was 408 ton and that of S. glandulosa was 336 ton in the study area. 5. The productivity of S. nipponica was $235g\;m^{-2}yr^{-1}$ and the annual production was 86.4 ton, and those of S. glandulosa were $1,006g\;m^{-2}yr^{-1}$ and 80.3 ton in the study area.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.74-83
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• 2016

In order to improve the sour taste and foul odor of fermented soymilk, bacteria were isolated from kimchi and identified. Of the 89 bacterial strains isolated from kimchi, 3 isolates produced fermented soymilk with a sour taste and foul odor. The selected bacterial strains R53, R83, and R84 were identified by morphological, biochemical, and 16S rRNA analyses as Weissella koreensis. The strain R83, which produced fermented soymilk having the mildest sour taste and foul odor, was selected for further investigation and named W. koreensis KO3. The optimum culture condition for the fermentation of soymilk by W. koreensis KO3 was at $30^{\circ}C$ for 12 h. When soymilk was fermented under the optimum culture conditions, the viable cell count reached up to $8.71{\times}10^8CFU/ml$ and pH and acidity reached as low as 6.02 and as high as 0.33%, respectively. Twenty-seven amino acids and their derivatives were detected in fermented soymilk. The amounts of serine, glycine, threonine, alanine, and aspartic acid, which contribute to a sweeter taste, increased during fermentation. Orinithine, which was not detected before fermentation, increased during fermentation. Sensory evaluation showed that W. koreensis KO3-fermented soymilk has improved bean, roasted nut, and sour flavors as well as an enhanced mouthfeel, appearance, preferability, and overall acceptability compared with those of standard fermented soymilk. With further study and development, soymilk fermented by W. koreensis KO3 could serve as a health-promoting food with favorable sensory qualities.

• Korean Journal of Environment and Ecology
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• v.15 no.3
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• pp.213-223
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• 2001

This study was carried out to clarify the distribution pattern of Salicaceae species which are considered as obligatory riparian vegetation, and also the correspondence between their distribution and the environment factors. Eighty-three study sites by stratified sampling were selected from the upstream to the downstream of An-sung stream. Vegetation factors such as coverage by species, disturbance, etc., and environmental factors including microtopography, soil properties, etc., measured and analyzed. Salicaceae species were identified as total 2 genera, 11 species through all study area, and the average occurring species were 2.8 species.5. koreensis among other species showed highest occurring frequency at An-sung streams, and also it was distributed widely through study area. S. gracizistyla was mainly fecund at upstream sites, where sandy soil texture and high longitudinal slope were developed. S. purpurea vats. japonica was mostly observed in the sandy soil, the same as S. gracilistytu and however, was not dominant but rather mixed with S. gracitistyta and S. koreensis. On the other hand, distribution of S. glandulosa were closely related with littoral zone of the lake and the lower sea level with sandy loam and loamy sand Boils of high organic matter content. Under CCA, canonical correspondence analysis, distribution of Saticaceae species was positively correlated with environmental gradients such as soil properties along to topography.

• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.277-289
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• 1997

Electrophresis methods were used to examined the degree of genetic relatedness and divergent times on the 4 genera 4 species of the family Corvidae and 1 species of the Family Cinclidae. Genetic relatedness between two families and between 4 genera of Corvidae showed similar to those reported at comparable taxonomic levels in other bird. But it appears to be considerably less than that of non avian taxa. Genetic relatedness between Garrulus glandarius brandtii and Corvus corone orientalis was the most close related(S=0.81), whereas Pica pica sericea(S=0.72) and Cyanopica cyanus koreensis(S=0.68) were showed less close relatedness respectively. The presumed divergent time between two families was 3.9 million years before present. Whereas among the 4 species of corvidae, the presumes divergent times of Cyanopica cyanus koreensis and Pica pica sericea were about 1.9 and 1.6 million years before present respectively, and between Garrulus glandarius brandtii and Corvus corone orientalis was showed recently about 1.0 million years before present

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.247-259
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• 2008

Terminal-restriction fragment length polymorphism (T-RFLP) analysis, one of rapid culture-independent microbial community analysis methods, was used to determine the lactic acid bacterial complexity and dynamics during kimchi fermentation at $15^{\circ}C$ and $4^{\circ}C$. At both temperatures, the common presence of Leuconostoc mesenteroides, Lc. inhae, Lc. kimchi, Weissella koreensis, W. cibaria, Lactobacillus sakei, Lb. curvatus, Lb. plantarum, Lb. paraplantarum, Lb. pentosus, and Lb. brevis was predicted. Lc. citreum and Enterococcus faecalis were detected at $15^{\circ}C$ and $4^{\circ}C$, respectively. W. koreensis predominated during the mid stage of kimchi fermentation whereas lactobacilli were dominants during later stage. Lb. sakei and Lb. curvatus became dominants regardless of fermentation temperature but the growth of Lb. plantarum, Lb. paraplantarum, Lb. pentosus, and Lb. brevis was restricted at psychrophilic temperature. Some species of leuconostocs were maintained until the later stage of kimchi fermentation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.257-264
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• 1986

The Chromosomes of five cobitid fishes, Cobitis taenia taenia, C. taenia lutheri, C. taenia striata, C. longicorpus and C. koreensis were studied. The karyotypic studies were based on the observations from the flame-drying preparations. The results obtained such as the number of somatic chromosomes, the type of chromosomes according to the centromeric loci and the number of chromosomal arm(AN) were as follows: C. longicorpus, 2n=50, 12m-8sm-30a, AN=70; C. koreensis, 2n=50, 10m-12sm-28a, AN=72; C. taenia taenia, 2n=48, 14m-4sm-30a, AN=66: C. taenia lutheri, 2n=50, 10m-6sm-34a, AN=66; and C. taenia striata, 2n=50, 10m-6sm-34a, AN=66. Peculiarly, in the case of C. taenia lutheri the chromosome number of somatic diploid was found to be 48-51, however, the number of chromosomal arm was 66, irrespective of the difference in the numbers of each somatic genome. It was confirmed there exists the Robertsonian event, one of the chromosomal polymorphism in C.t. lutheri. It was remarked taxonomically that the karyotype of C. taenia taenia of Korea having 48 diploid chromosomes was not identical with that of Europe and Japan with 50 chromosomes. Based on the karyotype analysis the Korean cobitid fishes can be classified roughly into three species groups according to arm numbers and diploid numbers; 1) C. taenia taenia, C. taenia lutheri, C. taenia striata 2) C. koreensis, C. longicor pus, C. rotundicaudata and 3) C. granoei.

• Korean Journal of Plant Taxonomy
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• v.39 no.4
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• pp.254-263
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• 2009

The distribution and habitat characteristics of Echinosophora koreensis (Nakai) Nakai were investigated to compile basic data for conservation and restoration. The species Echinosophora koreensis is distributed within fourteen regions of the Korean Province of Gangwon, including Yanggu-gun, Inje-gun, Cheorwon-gun, Chuncheon-si and Hongcheon-gun. Natural habitats were located at altitudes of 192-626 m, with inclinations of $1-45^{\circ}$. One hundred and fifty seven vascular plant taxa were identified from 42 quadrats in 14 habitats. Dominant species among the woody plants, based on importance value, were Pinus densiflora and Quercus dentata in the tree (T1) layer, Quercus variabilis, Pinus densiflora and Quercus mongolica in subtree (T2) layer, and Fraxinus rhynchophylla, Prunus sargentii, Zanthoxylum schinifilium, and Ulmus davidiana var. japonica in the shrub (S) layer. Importance values for members of the herb layer were: Echinosophora koreensis 28.34%; Polygonatum odoratum var. pluriflorum 10.21%; Spodiopogon sibiricus 7.60%; Atractylodes ovata 4.77% and Carex lanceolata 4.13%. The importance values of the last four species were high, so they were at affinity with Echinosophora koreensis in their habitats. Average species diversity was 1.03, and evenness and dominance were found to be 0.82 and 0.16, respectively. The soil types were sandy loam and loam. Average field capacity was 13.28%, and the organic matter and soil pH were 6.70% and 5.77, respectively.

• Journal of Korea Water Resources Association
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• v.46 no.9
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• pp.957-967
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• 2013

High turbidity submersion due to torrential downpour is one of the factors that influences the plant growth. This study is focused on analyzing the plant's growth rate for Salix species such as gracilisyla, koreensis, glandulosa when these trees are waterlogged. The length of shoots for this control group in the natural state is 33.4% (gracilisyla), 24.3% (koreensis), 23.9% (glandulosa), however, they stopped growing in submersion. Compared to the leaf number of Salix species of this control group in the natural state, 144.5% (gracilisyla), 77.3% (koreensis), 40.3% (glandulosa) in the natural state 30 days, in 30 days submersion, the number of leaves is zero except koreensis. In the results of this experiment, Salix species stopped growing quickly when submersed. This study concludes that it is necessary to plant eco-friendly plants around the slope of the reservoir and dam where flooding takes place frequently.

• Journal of Veterinary Clinics
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• v.26 no.6
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• pp.586-590
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• 2009

Horsehair worms (Chordodes koreensis) develop as parasites in the bodies of grasshoppers, crickets, cockroaches, and some beetles. Chordodes koreensis is an accidental parasite of humans, livestock, or pets and poses no public health threat. The male of Chordodes koreensis in the later larval stage from canine vomitus was investigated by the scanning and transmission electron microscopy. In cross sections, the body wall is composed of four components namely epicuticle, cuticle, epidermis, and muscle layers. The parenchymal tissue fills the rest of the body and surrounds the visceral organs such as intestine, and ventral nerve cord but testes were not found. The epicuticle is a thin superficial layer whose surface shows rows of polygonal elevations called areoles. The cuticle has 17 layers of collagenous fibers spirally wound about the long axis of the worm. The section through the cuticle reveals the layers of large fibers cut obliquely lengthwise, alternating with layers of fibers sectioned obliquely crosswise. The layers of large fiber formed a double helix about longitudinal axis of the worm. The epidermis is a single layer. The muscles were interrupted by the nervous lamella in the only midventral portion. The medulla of muscle plate is composed of lightly stained cytoplasm, mitochondria, weakly developed endoplasmic reticulum, and glycogen granules. Between the medulla of a cell and the plasmalemma lies a broad cortical zone of myofilaments. The circular muscles are absent. The characteristic feature of the cytoplasm is that there was no content in peripheral mesenchyme, but was an abundance of large clear vacuoles which give the cytosome a foamy appearance. The nucleus of mesenchyme is not easily identified in our specimens.