• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.521-547
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• 2018

To provide fundamental information to areas that lack data on the plant resources and the ecosystem, this study conducted a survey on the vascular plants in Mt. Jigisan in Hongseonggun. The vascular plants identified during the six-round field surveys were a total of 443 taxa: 96 families, 286 genera, 391 species, 7 subspecies, 40 varieties, 3 forms, and 2 hybrids. On floristic regional of Korea, Mt. Jigisan is deciduous broad-leaved and conifer-mixed forest which is south province of Korean peninsula. 4 taxa of Korean endemic plants such as Populus ${\times}$ tomentiglandulosa, Forsytsythia koreana, Forsytsythia ovate, and Iris rossii var. latifolia were collected. The vascular plants on the red list according to IUCN evaluation basis were found to be 6 taxa: Vulnerable (VU) species of Forsytsythia ovata, Least Conern (LC) species of Chionanthus retusus, Pseudoraphis ukishiba, and Cymbidium goeringii, and Not Evaluate (NE) species of Panax ginseng, and Fimbristylis verrucifera. The floristic regional indicator plants were found 27 taxa: 2 taxa of grade V, 3 taxa of grade IV, 6 taxa of grade III, 4 taxa of grade II, and 12 taxa of grade I. The specific distribution plants were found 27 taxa: 4 taxa of northern part of plants, 12 taxa of southern part of plants, 10 taxa of isolation distribution of plants, and 1 taxon of recently reported Viola betonicifolia var. albescens. The invasive alien plants were identified as 67 taxa. The naturalized index (NI) was 15.12%, and urbanization index (UI) was 20.9%, respectively.

• Korean Journal of Forensic Psychology
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• v.13 no.2
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• pp.121-145
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• 2022

The current study applied the random forest algorithm to Korean crime victim survey data collected biennially between 2010 and 2018 to explore the relationship between crime/victim characteristics and the victim's criminal damages. A total of 3,080 cases including gender, age (life cycle stage), type of crime, perpetrator acquisition, repeated victimization, psychological damage (depression, isolation, extreme fear, somatic symptoms, interpersonal problems, moving out to avoid people, suicidal impulses, suicide attempts), and emotional changes after victimization (changes in self-protection confidence, self-esteem, confidence in others, confidence in legal institutions, and respect for Korean legal system/law) were analyzed. Considering the features of data that are difficult to apply traditional statistical techniques, this study implemented random forest algorithms to predict crime and victim characteristics using the victim's criminal damages (psychological damage and emotional change) and selected good predictors using VSURF function in VSURF package for R. As a result of the analysis, it was confirmed that the relationship between the type of crime and depression, extreme fear, somatic symptoms, and interpersonal problems, between perpetrator acquisition and somatic symptoms and interpersonal problems, and between repeated victimization and changes in respect for Korean legal system/law. Gender and life cycle stage (youth/adult/elderly) were found to be related to extreme fear and changes in self-protection confidence, respectively. However, more empirical evidence should be aggregated to explain the results as meaningful. The results of this study suggest that it is necessary to enhance the experts' knowledge and educate them on cases about the relationship between crime/victim characteristics and criminal damage. Strengthening their interview strategy and knowledge about law/rules were also needed to increase the effectiveness of the Korean victim assessment system.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.202-211
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• 2019

Oceanic islands are biologically important for their unique assemblages of species and high levels of endemism and are sensitive to environmental change because of their isolation and small species source pools. Habitat destruction caused by human landscape development is generally accepted as the main cause of extinction on islands, with exotic species invasion a secondary cause of extinction, especially on tropical islands. However, secondary impacts of human development (e.g., general degradation through resource use and exotic species introduction) are understudied on temperate islands. To determine secondary impacts of human development on the understory vegetation community, 90 field sites on Ulleung Island, South Korea, were sampled during the summer of 2016. Understory vegetation was chosen as it is a proxy for ecosystem health. Diversity and percent cover of introduced, native, and endemic species were tested against proximity to developed areas and trail usage using a model selection approach. Diversity was also tested against percent cover of three naturalized species commonly found in survey plots. The main finding was that distance to development, distance to town, and trail usage have limited negative impacts on the understory vegetation community within best-supported models predicting native and introduced cover and diversity. However, endemic species cover was significantly lower on high usage trails. While there are no apparent locally invasive plant species on the island at the time of this study, percent cover of Robinia pseudoacacia, a naturalized tree species, negatively correlated with plot diversity. These findings indicate that forests on Ulleung Island are not experiencing a noticeable invasion of understory vegetation, and conservation efforts can be best spent preventing future invasions.

• Korean Journal of Pharmacognosy
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• v.35 no.2 s.137
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• pp.134-138
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• 2004

A bioassay-guided fractionation of the whole extract of Viscum album var. coloratum Ohwi (Loranthaceae) led to the isolation of two triterpenoidal components; oleanolic acid (1) and ${\beta}-amyrin$ acetate (2), and a flavonoid, homoflavoyadorinin B (3) as well as large quantity of free fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble fraction and BuOH soluble fraction of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system), and HCT-15 (colon) in vitro, whereas the remaining water soluble fraction exhibited a poor inhibition. The intensive phytochemical investigation of the EtOAc soluble fraction and BuOH soluble fraction of the extract indicated that the oleanolic acid (1) and large amounts of free fatty acid mixtures might be attributed to the in vitro antitumoral property of the whole extract of Viscum album var. coloratum.

• Korean Journal of Pharmacognosy
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• v.39 no.4
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• pp.347-351
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• 2008

The methanol (MeOH) extract of the rhizome of Alpinia officinarum Hance (Zingiberaceae) demonstrated a potent inhibition on the proliferation of cultured human tumor cell lines such as MES-SA (human uterine carcinoma cell line), MESSA/DX5 (multidrug resistant subline of MES-SA), HCT-15 (human colorectal adenocarcinoma cell line), HCT15/CL02 (multidrug resistant subline of HCT15). The MeOH extract was fractionated into four portions by serial solvent partition, ie., methylene chloride (CH2Cl2) soluble part, ethylacetate (EtOAc) soluble part, n-butanol (BuOH) soluble part and remaining water layer. Among them, the $CH_2Cl_2$ soluble part of the extract exhibited a most potent inhibition on the proliferation of tested tumor cell lines. Bioassay-guided fractionation of the $CH_2Cl_2$ soluble part led to the isolation of five diarylheptanoid and two flavonoid constituents, i. e., galangin (1), 7-(4"-hydroxy-3"-methoxyphenyl)-1-phenylhept-4-en-3-one (2), 1,7-diphenyl-5-hydroxy-3-heptanone (3), trans,trans-1-(3'-methoxy-4'-hydroxyphenyl)-7-phenyl-5-ol-4,6-dien-3-heptanone (4), 5-methoxy-7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-3-heptanone (5), kaempferide (6), 5-hydroxy-7-(4"-hydroxy-3"-methoxyphenyl)-1-phenyl-3-heptanone (7). Structures of the isolated active components (1 - 7) were established by chemical and spectroscopic means.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.308-313
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• 2003

A bioassay-guided fractionation of the stem bark extract of Eucommia ulmoides Oliver (Eucommiaceae) led to the isolation of three iridoid constituents, genipin (1), geniposide (3), geniposidic acid (4) as well as $({\pm})-guaiacylglycerol$ (2) and fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble part and BuOH soluble part of the extract demonstrated a potent inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited a poor inhibition. The intensive investigation of the EtOAc soluble part and BuOH soluble part of the extract yielded genipin, guaiacylglycerol, geniposide, geniposidic acid and large amounts of fatty acid mixtures as active components.

• Korean Journal of Pharmacognosy
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• v.40 no.3
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• pp.229-232
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• 2009

The ethanol (EtOH) extract of the branches of Cotinus coggygria (Anacardiaceae) exhibited a significant inhibition on the yeast $\alpha$-glucosidase, one of the key enzymes related with diabetes mellitus, in a dose dependent manner, in vitro. The intensive phytochemical survey of the EtOH extract of the species by way of bioactivity-guided fractionation resulted in the isolation of 1,2,3,4,6-penta-O-galloyl-$\beta$-D-glucose (1) as an active principle responsible for the inhibition on $\alpha$-glucosidase, together with two related components 2 and 3. Compound 1 demonstrated a strong inhibition on the yeast $\alpha$-glucosidase, in vitro and $IC_{50}$ value was calculated as 0.96 mg/ml, when that of a reference drug, acarbose was estimated as 5.3 mg/ml. On the other hand, other related constituents of the species, 1,2,3,6-tetra-O-galloyl-$\beta$-D-glucose (2) and gallic acid (3) were exhibited relatively poor inhibition upon the yeast $\alpha$-glucosidase, respectively.

• Journal of Technologic Dentistry
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• v.22 no.1
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• pp.145-152
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• 2000

In order to select an effective antibiotic substance against oral resident bacteria, we were isolated from soil and texonomically analyzed. Seven hundred and eighteen strains were isolated on humic acid- vitamin agar(HV agar) and 220 strains were on methanol medium from three each paddy forest, field and riverside soil samples. So, during the screening of antibiotics from soil, we isolated microorganisms showing powerful antagonistic activity against oral resident bacteria. Microorganism was tested against 25 strains of bacteria, yeast and fungi. Among them, No. 248 strain exhibited the most strongly growth inhibition. So, the taxonomical analysis the isolated strain was found to be unknown Actinomyces sp. and was named No 248. A production of the antibiotics from No. 248 begins at the early exponential phase developed at the 72th hour under the optinum conditions. The property of No. 248 antimicrobial compound was very stable under acid(pH 3.0) and alkali(pH 10.0) treatment, but it was instable in heat treatment at $120^{\circ}C$. For the improvement of antibiotic activity, two mutants were isolated from strain No. 248 by the treatment of mutagenic agents, NTG and hydroxylamine. As a result, the mutant strains excreted the potent antibiotics to inhibit the growth of Candida albicans.

• Journal of Species Research
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• v.4 no.2
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• pp.97-108
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• 2015

As a subset study to discover indigenous prokaryotic species in Korea, a total of 29 bacterial strains assigned to the classes Alphaproteobacteria were isolated from various environmental samples collected from plant root, ginseng soil, forest soil, marsh, mud flat, freshwater and seawater. From the high 16S rRNA gene sequence similarity (>99.1%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 29 species included in Alphaproteobacteria is have been described in Korea; therefore 14 species of 9 genera in the order Rhizobiales, 7 species of 6 genera in the order Sphingomonadales and 4 species of 2 genera in the order Caulobacterales and 3 species in the order Rhodobacterales and 1 species in the order Rhodospirillales found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section.

• Journal of Species Research
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• v.7 no.1
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• pp.13-23
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• 2018

In 2016, as a part of the research program 'Survey of Korean Indigenous Species', diverse environmental samples were collected from various sources of freshwater, seawater, soil, wetland, reclaimed land, sand, pine forest, plant root, ginseng field, solar saltern, and caves. Thousands of bacterial strains were isolated from the diverse samples and identified based on 16S rRNA gene sequence analyses. The present study, as a phylogenetic subset of the primary research program, reports 24 unrecorded bacterial species in Korea that belong to the orders Rhizobiales and Sphingomonadales in the class Alphaproteobacteria. Based on the high 16S rRNA gene sequence similarities (>98.8%) and formation of a robust phylogenetic clade with the closest type species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 24 bacterial species have been described in Korea; therefore, 10 species of nine genera in the order Rhizobiales and 14 species of seven genera in the order Sphingomonadales are described for unreported alphaproteobacterial species in Korea. Gram reaction, colony and cell morphology, biochemical properties, and isolation sources are also provided in the species description section.