• The Korean Journal of Zoology
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• v.36 no.4
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• pp.545-555
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• 1993

뱀장어속(Anguilla)의 뱀장어(A. ioponica)와 무태장어(A. marmoruta) 및 꾀붕장어(Anago anogo)의 유전적 특징과 종간 유연관계를 밝히기 위하여 isozyme 분석과 mtDNA 분석을 실시하였다. Isozyme 분석결과 20개의 효소 및 비효소단백질에서 총 39개의 유전자를 검출하였고 각종 특유의 genetic marker를 확인하였다. 3종의 평균 유전적 변이는 뱀장어가 HD=0.057. HG=0.065, 무태장어는 HD=0.067 HG=0.053, 체불장어가 HD=0.018. HG=0.020으로 각각 나타났다. 뱀장어와 무태장어의 평균 종간유전적 근인관계는 S=0.420 (D=0.869)로 멀게 나타났다. 6 base를 인지하는 10종류의 제한효소를 처리한 결과 mtDNA 절편양상은 각 종내에서 동일하게 나타났으나 각종간에 차이를 보였고, 종간 평균염기 치 환율은 뱀장어와 무태장어가 p=3.4%, 뱀장어속 2종과 꾀붕장어는 p=9.6%로 나타났다.

• Animal Systematics, Evolution and Diversity
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• v.18 no.1
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• pp.23-33
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• 2002

Two lichomolgoid copepods, Lichomolgus inflatus Tanaka and Philoconcha paphiae Yamaguti, both known very rarely since the original descriptions, are redescribed based on the specimens discovered as associates with the bivalve Dosinorbis japonicus from the Korea Strait. Lichomolgus inflatus is very closely related to L. chamarum Humes, but can be differentiated by the features of the rostrum and genital double-somite. Philoconcha paphiae is found to have an extremely variable leg armature. This is the first discovery of the two species of copepods outside the Japanese waters.

• The Korean Journal of Ecology
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• v.23 no.3
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• pp.241-253
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• 2000

The degree to which microenvironmental factors are linked to spatial patterns of vegetational factors within ecosystems has important consequences for our understanding of how ecosytems are structured and for conservation of rare species in ecosystems. We studied this relationships between the spatial patterns of microenvironmental factors and vegetational factors in temperate hardwood forest in Mt. Jumbong Biological Reserve Area, Korea. To do this, environmental and vegetational factors from 196 micropoints in a 0.49 ha plot were investigated. Most of all environmental factors and vegetational factors showed the variations among micropoints. Microtopographic factors, litter depth, soil moisture content and relative light intensity at this site were spatially dependent at a scale of 14∼62 m. Coverage of tree and shrub layer and species diversity of herb layer in autumn were spatially dependent at a scale of < 15 m. Species richness and species diversity of herb layer in spring and species richness of herb layer in autumn were spatially dependent at a scale of 28∼48 m. Multiple regression analysis showed that spatial patterns of species richness and species diversity of herb layer in spring and autumn were affected by litter depth, slope, subtree layer, shrub, Sasa borealis etc. The best predictor for the spatial patterns of species richness and species diversity of herb layer at this site was the spatial pattern of litter depth. Species richness and species diversity of herb layer showed strongly negative correlation with litter depth. We estimate that the spatial pattern of litter depth at this site were affected by direction of wind, microtopography and spatial pattern of shrub layer.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.121-128
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• 2003

This study was carried out to identify the phylogenetic relationship of Phellinus species and to know its distribution by comparing the DNA sequences of internal transcribed spacer regions(ITS1 and IST2) and 5.8S ribosomal DNA (rDNA) repeat unit. The Phellinus species had their specific sequences in IST1 and 2 regions depending on suedes. The comparison of the ITS sequences of standard strains indicated that the sequences of ITS1 were more variable than those of ITS2. Nine strains of the commercial products of Phellinus species used in this study were identified as P. lintues, P. baumii, P. igniarius, and P. pini. Most of commercial species were P. pini and P. baumii, and P. gilvus was not found. Also, P. linteus was only found in form of mycelial culture rather than fruiting body. Moreover, the species-specific primers were designed based on ITS sequence data. Each species-specific primers were bound in P. lintues(ITSF-PL2R), P. baumii(PB1F-ITS4R), P. igniarius(IF1-IR3), P. pini(PF1-PR3), and P. gilvus(GF2-GR4), respectively. These primer sets would be useful fer the detection of specific-species among unidentified Phellinus species rapidly.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.533-537
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• 2015

Micro-algae Chlorella vulgaris (C. vulgaris) is an important source for bio-diesel because of the high content of neutral lipids. In this study, we intended to induce mutants of C. vulgaris by UV-B irradiation. C. vulgaris was first exposed to UV-B for 1, 2, 3, 4, 5 min. As the UV-B exposure time increased, the cell viability and pigment content were decreased. Mutants of C. vulgaris were also induced through ultraviolet irradiation and two strains were selected with respect to lipid contents, where were named as 'UM10', 'UM15'. They were then cultivated in the same way as to the wild type. After 21 days of cultivation, the cell growth, dry cell weight, pigment contents, and lipid contents were measured for investigating characteristics of mutants. As a result, the cell growth and dry cell weight of both mutants increased about 1.4 and 1.5 times, respectively compared with those of wild type. In addition, chlorophyll and carotenoid contents were measured in order to investigate pigment contents in micro-algae through photosynthesis. It was shown that chlorophyll and carotenoid contents of both mutants decreased about 10% compared to those of wild type. Lipid contents in UM10 and UM15 increased about 1.2 and 1.5 times, respectively compared to that of wild type.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.151-160
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• 1998

The Leuconostoc paramesenteroides dominated at refrigeration temperature range was isolated from kimchi, and improved its growth properties by mutation for competitive growth against Lactobacillus plantarum at lower pH. It was found that the minimal pH for the wild type Leuconostoc paramesenteroides Pw growth was pH 4.5 adjusted with HCI and pH 5.0 adjusted with organic-mixture (lactic acid:acetic acid=1:2), respectively. The mutant P-100 could grow in pH 4.0, 4.5, respectively, in MRS broth. Two strains Pw and P-100 were added into kimchi as starter and compared the quality characteristics of kimchi. The total acceptability of Pw and P-100 inoculated kimchi were evaluated better than that of control kimchi (no starter added) by sensory test and extended the optimal pH range of kimchi up to about 2.2, 2.5 times, respectively. In kimchi added P-100, the succinic acid was more abundant than others and the total number of Lactobacillus plantarum was down about 2.5 times in contrast to control kimchi.

• FLOWER RESEARCH JOURNAL
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• v.16 no.2
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• pp.128-133
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• 2008

This study was conducted to select new variants with different characteristics in plant height, leaf color, and petal color of plantain lily (Hosta plantaginea) and Japanese farfugium (Farfugium japonicum). After 10-30Gy ${\gamma}-ray$ irradiation to seeds of both species, seed germination, variant induction, growth of variants, and survival ratios were estimated. Days required for seed germination were lengthened and % seed germination decreased as the dosage of ${\gamma}-ray$ increased over 20Gy. Lethal dose ($LD_{50}$) for plantain lily and Japanese farfugium were 30Gy and 25Gy, respectively. Plantain lily and Japanese farfugium treated by more than 20Gy ${\gamma}-ray$ showed dwarf characteristics in growth, and variations in leaf and petal colors. Total 166 variants in plantain lily were induced by ${\gamma}-ray$ irradiation in a $M_1$ generation, among which 12 promising variants were selected in a $M_2$ generation. Total 57 variants of Japanese farfugium were induced by ${\gamma}-ray$ irradiation in a $M_1$ generation, among which nine promising variants were selected in a $M_2$ generation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.424-437
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• 1993

About three fourths of total variability of zooplankton in Asan Bay was associated with season and the difference between inner bay and outer bay was relatively small. However, the differences in percent compositions of major taxa at inner bay and outer bay increased gradually with time, suggesting the change of ecosystem in this bay due to the human exploitation such as reclamation. Seasons of maximum abundances were different among the taxa but consistent for each taxon throughout the three survey years. Calanus sinicus and Acartia bifilosa showed maximum abundance in spring. Sagitta crassa, Paracalanus parvus, A. pacifica, Tortanus spinicaudatus, Corycaeus affinis and Decapoda larva were most abundant in summer. Labidocera euchaeta and Bivalve larva appeared most abundantly in fall. But in winter no taxon showed maximum. In general, low abundance with many species in fall, low abundance and few taxa in winter, increase in both number of taxa and abundance in spring, and high abundance and many taxa in summer were observed. A hypothesis for the observed patterns was suggested although more evidences were needed to support this.

• Journal of fish pathology
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• v.11 no.2
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• pp.89-96
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• 1998

Marine birnavirus (MABV) has wide host range in marine organisms. To clarify various infection properties of MABV in different host species, in vitro study was performed by subculture for 10 passages in several fish cell lines. In CHSE-214, RTG-2 and RSBK-2 cells, the virus produced high yield of virus. Typical CPE with high protein expression was observed in these cells. On the contrary, the virus grown in EPC, FHM and BF-2 cells exhibited no CPE appearance although virus protein was detected. In EPC and FHM cells, the virus titer increased in later passages. The plaque size was distinctly bigger in CHSE-214, RTG-2 and RSBK-2 cells than in other cell lines. The nucleotide sequence of VP2/NS junction region on genome segment A exhibited one specific nucleotide change at 195. The different infection properties in several cell types performed in the present work might reflect in vivo MABV infection in various host species occurring in natural conditions.

• Korean Journal of Plant Taxonomy
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• v.33 no.4
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• pp.359-371
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• 2003

Numerical analyses using 28 morphological characters from 14 populations of four Korean Orostachys species were conducted to investigate infra-specific variation and to test species relationships. The resulting phenogram recognized three distinct clusters, and the populations of O. malacophyllus, O. iwarenge and O. minutus were closely related each other. The populations of O. japonicus from Gaeksanri (I) and Gadeuk-do were isolated from the remaining populations of the species, and it suggests that the ranges of morphological variation within the species are significant, and related to the previous cytological variation. The Jungdongjin population of O. malacophyllus was not grouped together with the same species, but was clustered with the populations of the O. japonicus, and suggested that it seems to be an unrelated population in O. malacophyllus. The results of the PCA analysis recognized two distinct groups: the populations of O. japonicus and remaining species populations. The populations of O. malacophyllus, O. minutus and O. iwarenge placed within the closely related species.