• Journal of fish pathology
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• v.20 no.2
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• pp.147-160
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• 2007

Four strains of water mold, ChS-E0511, RaT-E0511, RaT-A0512 and MaS-F0512, were isolated from salmonid fish and/or their eggs taken from culture farms in Yangyang, Milyang and Pyeongchang, Korea in 2005. Descriptions of their morphological aspects, the results of the phylogenetic analysis conducted, and the sequence of the small sub-unit 18S rRNAs of the isolates confirmed that they all belong to the species Saprolegnia parasitica. Only one species, ChS-E0511, which was isolated from fertilized eggs of the chum salmon, was classified as part of the S. parasiticaGroup 1 according to its oogonia and gemmae production. The chemotherapeutic effects of various chemicals on the ChS-E0511 strain were assessed from the inhibitory effects of growth in GY media and the relative ratio of eyed eggs to fertilized eggs of the rainbow trout. Malchite green, a prohibited substance in food animals, was better than others, such as the Opuntia ficus-indicaextract, 2-bronopol, and sodium chloride. These results suggest that the fungi isolated from salmonids and/or their eggs identified as S. parasitica were composed of more than two groups. These isolates will be useful in an intensive evaluation of therapeutic agents.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.142-150
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• 2020

This experiment was conducted to set ideal harvest time for itallian ryegrass (IRG) seed in reclaimed land. For IRG 'Kowinearly' variety sown in both autumn and spring, the peak growth in reclaimed land occurred in 20-30 days after heading. Plant height of IRG seedings in the spring was 90.4% of the fall-sown's plants. The yield of IRG seeds in reclaimed land was generally lower than that of farm land due to poor growth conditions. After heading, the lodging and shattering increased gradually with time. The highest yield of seed in the fall-sown trial treatment was 238 kg/10a. However, in the spring-sown treatment, the highest yield reached 169 kg/10a, which was 71% that of the fall-sown treatment. To set optimum harvesting time for IRG seed, morphological changes in the plant, moisture content of seed, and germination rate were analyzed according to time series after heading. After heading, IRG stem color had turned pink in 18 days and seed color also changed after 20 days. Following 20-25 days after heading, the seed moisture content decreased to below 55% and germination rate increased to over 90%. Therefore optimum harvesting time for IRG 'Kowinearly' variety in reclaimed land was 20-30 days after heading because germination rate and yields were high and shattering percentage was low.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.299-304
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• 2003

A strain YB-9 was isolated from soil as a producer of the extracellular ${\beta}-D-galactosidase$, which catalyzes the hydrolysis of lactose. The strain YB-9 was identified as Streptomyces sp. on the basis of its cultural, morphological and physiological properties. After treating culture supematant of the isolate with ammonium sulfate $(15{\sim}70%)$, the precipitated protein was used as a crude ${\beta}-galactosidase$ for analyzing its reaction properties with $para-nitrophenyl-{\beta}-D-galactoside$ $(pNP-{\beta}Gal)$ and lactose as substrates. The {\beta}-galactosidase showed its maximal activity at pH $6.0{\sim}6.5$ and $60^{\circ}C$. The hydrolyzing activity of ${\beta}-galactosidase$ for both $pNP-{\beta}Gal$ and lactose was decreased by galactose. Its hydrolyzing activity for lactose was slightly decreased by glucose, but the activity for $pNP-{\beta}Gal$ was increased to 1.3-folds by glucose. Especially, its hydrolyzing activity was not affected for lactose and was increased to 1.6-folds for $pNP-{\beta}Gal$ by xylose.

• Journal of Microbiology and Biotechnology
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• v.18 no.8
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• pp.1459-1469
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• 2008

Using a rotating biological contactor modified with a sequencing bath reactor system (SBRBC) designed and operated to remove phosphate and nitrogen [58], the microbial community structure of the biofilm from the SBRBC system was characterized based on the extracellular polymeric substance (EPS) constituents, electron microscopy, and molecular techniques. Protein and carbohydrate were identified as the major EPS constituents at three different biofilm thicknesses, where the amount of EPS and bacterial cell number were highest in the initial thickness of 0-100${\mu}m$. However, the percent of carbohydrate in the total amount of EPS decreased by about 11.23%, whereas the percent of protein increased by about 11.15% as the biofilm grew. Thus, an abundant quantity of EPS and cell mass, as well as a specific quality of EPS were apparently needed to attach to the substratum in the first step of the biofilm growth. A FISH analysis revealed that the dominant phylogenetic group was $\beta$- and $\gamma$-Proteobacteria, where a significant subclass of Proteobacteria for removing phosphate and/or nitrate was found within a biofilm thickness of 0-250${\mu}m$. In addition, 16S rDNA clone libraries revealed that Klebsiella sp. and Citrobacter sp. were most dominant within the initial biofilm thickness of 0-250${\mu}m$, whereas sulfur-oxidizing bacteria, such as Beggiatoa sp. and Thiothrix sp., were detected in a biofilm thickness over 250${\mu}m$. The results of the bacterial community structure analysis using molecular techniques agreed with the results of the morphological structure based on scanning electron microscopy. Therefore, the overall results indicated that coliform bacteria participated in the nitrate and phosphorus removal when using the SBRBC system. Moreover, the structure of the biofilm was also found to be related to the EPS constituents, as well as the nitrogen and phosphate removal efficiency. Consequently, since this is the first identification of the bacterial community and structure of the biofilm from an RBC simultaneously removing nitrogen and phosphate from domestic wastewater, and it is hoped that the present results may provide a foundation for understanding nitrate and phosphate removal by an RBC system.

• Journal of Conservation Science
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• v.36 no.2
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• pp.93-102
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• 2020

A lichen is a complex microorganism comprising fungi and algae. Various lichens are commonly found in cultural heritage and are reportedly related to weathering. Lichens are commonly studied in Europe; however, few reports exist on lichens in Korean cultural heritage. The present study was conducted as part of the Korean National Arboretum's "A study on the Fungus and Lichen." We report the lichen diversity found at the Placenta Chambers of King Sejong's Sons, Seongju. A total of 65 lichens were collected from 19 placenta chambers and one memorial stone. We identified 40 species belonging to 10 genera, 17 families, and 23 orders. Morphological identification revealed that foliose lichens in the form of leaves(24, 36.9%) and crustose lichens in the form of crust(24, 36.9%) were distributed at a higher percentage than that of fruticose lichen in the form of branches(17, 26.2%). Xanthoparmelia coreana(foliose lichen) and Lepraria sp.(crustose lichen) were the most collected lichens and were distributed on 19 chambers. In addition, Clodonia, a fruticose lichen, had the highest species diversity with eight species. The highest species diversity of lichens was identified on the chamber of Prince Kyeyang(16 lichens), whereas the chamber of Prince Geumsung had the lowest species diversity(five lichens). This study will be used as primary data for the study of distribution of lichen diversity in Korean cultural heritage.

• The Korean Journal of Malacology
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• v.32 no.1
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• pp.55-62
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• 2016

In this study, an attempt has been made to analyze the morphology of Cephalopods distributed in Korea and collected samples from South-East Asian countries including Thailand, Indonesia, Vietnam, and China. A phylogenetic analysis was performed using the mitochondrial gene, Cytochrome c oxidase subunit I (COI) to understand the genetic divergences of the species and validate their origins. For achieving the objectives, samples were collected directly from Thailand Hat Yai, Songkhla, Indonesia Medan, Vietnam Ho Chi Minh, and Vung Tau in August 2015 and from China in September 2015. A total of 23 species of Cephalopods were identified falling under three orders, four familyies and nine genus. The species were distributed under Order: Octopoda (1 family, 3 genus, and 9 species), Order: Sepiolioda (1 family, 2 genus, and 8 species), and Order Teuthoidea (2 family, 4 genus, and 6 species). 23 species which is 1 family 3 genus 9 species in Octopoda, 1 family 2 genus 8 species in Sepiolioda, 2 family 4 genus 6 species in Teuthoidea. Phylogenetic analysis using COI gene was conducted for 18 species. For the remaining 5 species sequencing results showed severe variation and hence were not considered further. The COI phylogenetic analysis for the 18 species of Cephalopods were found consistent with the morphological identification. The excluded species will be subjected for a further detailed analysis.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.187-191
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• 1970

This experiment was carried out to isolate osmophilic yeasts for higher concentration of NaCl than 20 per cent may affect greatly the fermentation of soy sauce. 6 strains of yeasts were selected from the soy sauce mashes at the fermentating periods and identified observing their morphological characteristics. Their salt-resistance and effects upon the flavor of soy sauce were examined. The results obtained were as follows: (1) The strain $T_3,T_5,$ and $T_{11},\;T_8,\;T_9,\;and\; T_{10},$ selected were identified Saccharomyces cerevisiae group II, Debaryomyces nicotianae, Saccharomyces chevalieri, Saccharomyces rouxii and Saccharomyces rosei, respectively. (2) They were more salt-resistant on the liquid media than on the solid media in the case of cultures on the media containing more than 26 per cent of NaCl. (3) They were grown on the media containing 5-23 per cent of NaCl better than containing none of NaCl. (4) The strain $T_3,\;T_8,\;T_9,\;and\; T_{10}$ were grown on the media containing up to 28 per cent of NaCl, and $T_5\;and\;T_{11}$ up to 32 per cent of NaCl is the case of liquid cultures. (5) Among them, the strain $T_9$ showed the best alcohol fermentation ability and the best fermentative flavor, and $T_5\;and\;T_{11}$ formed moldy smell and pellicle.

• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1027-1036
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• 2020

Stipa purpurea is a unique and dominant herbaceous plant species in the alpine steppe and meadows on the Qinghai-Tibet Plateau (QTP). In this work, we analyzed the composition and diversity of the culturable endophytic fungi in S. purpurea according to morphological and molecular identification. Then, we investigated the bioactivities of these fungi against plant pathogenic fungi and 1-aminocyclopropane-1-carboxylate deaminase (ACCD) deaminase activities. A total of 323 fungal isolates were first isolated from S. purpurea, and 33 fungal taxa were identified by internal transcribed spacer primers and grouped into Ascomycota. The diversity of endophytic fungi in S. purpurea was significantly higher in roots as compared to leaves. In addition, more than 40% of the endophytic fungi carried the gene encoding for the ACCD gene. The antibiosis assay demonstrated that 29, 35, 28, 37 and 34 isolates (43.9, 53.1, 42.4, 56.1, and 51.5%) were antagonistic to five plant pathogenic fungi, respectively. Our study provided the first assessment of the diversity of culture-depending endophytic fungi of S. purpurea, demonstrated the potential application of ACCD activity and antifungal activities with potential benefits to the host plant, and contributed to high biomass production and adaptation of S. purpurea to an adverse environment.

• Korean Journal of Plant Taxonomy
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• v.36 no.3
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• pp.217-225
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• 2006

Among the seven taxa of the genus Vigna, Leguminosae vegetated in Korea peninsula, only two taxa, V. unguiculata subsp. unguiculata and V. vexillata var. tsusimensis, are recognized in Vigna. The rests are still remained in the genus Phaseolus in many floras and illustrations of Korea although they were placed into the genus Vigna by Verdcourt in 1970. There has been misidentification between V. angularis var. nipponensis and V. nakashimae because of their similar morphological characters and habit. It was also found that V. nakashimae has not been recorded in many floras. Objectives of this study are 1) to discuss the taxonomic differences between Vigna and Phaseolus, 2) to have a recommendation for using correct scientific names of Vigna taxa, 3) to discuss the taxonomic characteristics of the subgenus Ceratotropis, and 4) to provide a simple taxonomic key of V. angularis var. nipponensis and V. nakashimae.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.545-563
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• 2007

The investigated vascular plants of Dok-do island were confirmed that consisted of 46 species, 1 subspecies, 1 varieties in total of 48 taxa growing spontaneously. 1 taxa of Pteridophyta, 36 taxa of Dicotyledon and 11 taxa of Monocotyledon identified. In 48 identified taxa in this study, total 13 taxa included Orobanche coerulescens Stephan, Fallopia sachalinensis (F. Schmidt) Rouse Decr., Lonicera insularis Nakai identified according to the Korean plant taxa for environmental assessment. Planting species were about 10 taxa included Pinus thunbergii Parl., Hibiscus syriacus L. and etc. Four species confirmed in this study such as between Chenopodium virgatum Thunb. and Chenopodium album L., Echinochloa crusgalli (L.) P.Beauv. and Echinochloa crusgalli var. oryzicola (Vasinger) Ohwi. were doubt on identification in taxonomic entity due to morphological characteristics. The dispersion type of Do-kdo plants were anemochore 31 taxa, zoodchore 8 taxa, hydrochore 2 taxa and the others by artificial means.