• Research in Plant Disease
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• v.23 no.1
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• pp.56-59
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• 2017

During growing season of 2011 to 2013, Sclerotinia rot symptoms consistently have been observed on basil in Yesan-gun, Chungcheongnam-do in Korea. The typical symptom formed initially brownish spot on leaf and stem, and then advancing margins, wilting the whole plant and blighting, eventually died. On the surface of diseased lesions was observed cottony, white, dense mat of mycelial growth, and sclerotia ($30-100{\mu}m$ diameter) formed on stem and leaf. Morphological and cultural characteristic on potato dextrose agar, color of colony was white and colorless chocolate, sclerotium of irregular shape of the oval was black and $5-50{\mu}m$ diameter in size. In pathogenicity test, necrosis and wilt of the inoculated stem were observed in all plants and the pathogen was reisolated from stems. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer rDNA sequence analysis, this fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia rot on basil caused by S. sclerotiorum in Korea.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.336-341
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• 2007

To investigate the variations of physico-chemical factors and microbial population, in ten stations at water region of coastal area of Chagwi-Do, Nutritive salts, water temperature, transparency, suspended solid, salinity, COD, DO, pH, heterotrophic bacteria, were analysed three times in September, November in 2004 and February in 2005. Heterotrophic bacteria in surface water was $3.5\times10^1\sim1.16\times10^3\;cfu\;mL^{-1}$, $0.4\times10^1\sim5.6\times10^1\;cfu\;mL^{-1}$, $0.4\times10^1\sim7.8\times10^1$ and bottom water counted $4.5\times10^1\sim1.0\times10^3\;cfu\;mL^{-1}$, $1.2\times10^1\sim1.5\times10^2\;cfu\;mL^{-1}$, $0.4\times10^1\sim4.4\times10^1\;cfu\;mL^{-1}$ in September, November 2004 and February 2005, respectively. The dominant species isolated from the coastal area of Chagwi-Do were identified to be Vibrio spp., Pseudoalteromonas spp. Psuedomonas spp, Bacillus spp., Alteromonas spp., Aeromonas spp., Psychrobacter spp., and Flavobacterium spp.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.360-366
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• 2013

This study was it conducted on effluent or river water close to discharge locations from a treatment plant, which were analyzed for the presence, phenotype and antibiotic resistance rates of Vancomycin Resistant Enterococci (VRE). The test results for isolation and identification of Enterococcus spp. showed that they all were VRE positive, with a total of 32 strains detected. Multiplex PCR was conducted for 32 strains, each of which were identified as E. faecium, and the results indicated that they were all confirmed as VRE, corresponding to the Van A phenotype. The results of E. faecium concentrations measured at various locations indicated that they were, on average, higher at the location of sewage treatment plants. The frequency of positive tests as well as the number of colonies was higher downstream of treatment plants. The minimum inhibitory concentration was inspected for 26 strains of discharged water samples from sewage water treatment plants, and 6 strains of river samples. Out of 19 antibiotics, 14 and 5 species showed resistance and sensitivity, respectively.

• Research in Plant Disease
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• v.8 no.1
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• pp.59-62
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• 2002

Anthracnose symptoms were observed on the community area in Sancheong-gun, Gyeongnam Province in Korea. The symptoms occurred on leaf and stem, and then plants eventually were died. Colony color was whitish gray to dark gray on potato dextrose agar. Conidia were single celled . colorless, cylindrical and was 10.2~20.4$\times$3.6$\times$6.0$\mu$m in size. Appressoria were dark brown, ovate to obovate and 6.2~10.5$\times$4.3$\times$8.6$\mu$m in size. Perithecia were brown to black in color and shaped as globose to obpyriform and 72.6~284.7$\mu$m in size. Asci were clavate to cylindrical in shape and 63.6~98.8$\times$8.3~12.5$\mu$m in size. Ascospores were cylindrical. fusiform, slightly curved at the center and 9.6~21.8$\times$4.0~6.0$\mu$m in size. Optimum temperature fur growth was 3$0^{\circ}C$. On the basis of mycological characteristics and pathogenecity test on host plants, the fungus was identified as Glomerella cingulata . This is the first report on the Anthracnose of achyranthes caused by Glomerella cingulata in Korea.

• Research in Plant Disease
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• v.13 no.1
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• pp.15-19
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• 2007

A wilt disease on the greenhouse-grown chrysanthemum occurred at Kumi, Masan and Busan, Korea in $2003{\sim}2005$. Symptoms of wilting, yellowing, and marginal burning started from lower leaves and progressed upward. Early symptoms often appeared on one side, involving only one part of the plant or one side of individual leaves or stems without a vascular discoloration. Vascular tissues of the infected leaf-base's discolored to brown. Fungal isolates obtained from discolored tissues were identified as Verticillium dahliae based on its cultural and morphological characteristics. The fungus showed whitish to creamy colony pattern with abundant dark brown to black elongated microsclerotia on PDA. Conidiophores were verticillately branched and conidia were ellipsoidal to sub-cylindrical shape, and measured as $2.5{\sim}8.8{\times}2.0{\sim}3.8{\mu}m$. Pathogenicity tests by root dipping resulted in similar symptoms observed in the naturally infected chrysanthemum in fields.

• Journal of Environmental Impact Assessment
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• v.20 no.2
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• pp.187-198
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• 2011

The objective of this study is to analyze the flora and forest vegetation of trails with high visitor density at Molundae. Nine quadrats of $20{\times}20m$ were selected for the survey. The survey was conducted from April to October 2010. The obtained results are summarized as follows. Plot1, plot2, plot3, plot4, plot6, and plot7 were located at slopes of $5{\sim}20^{\circ}$, 17~40m above sea level, and were formed with the colony of Japanese black pine(Pinus thunbergii Parl) and Japanese black pine(Pinus thunbergii Parl)-white oak(Quercus aliena Blume). Tree layer had the height of 8~20m, and the coverage of 50~70%, while subtree layer had the height of 3-8m, and the coverage 30~80%. On the other hand, shrub layer had the height of 2~4m, and the coverage of 10~30%, and herb had the height of 0.2~1m and coverage 5~20%. Plot5, plot8, and plot9 were located at the summit areas of 57~78m above sea level, and $0^{\circ}$ slope. Japanese black pine(Pinus thunbergii Parl) formed a community there. Tree layer was 8~20m high, and covered 60~70%, of the area, and subtree layer was 6~8m high, and coverage 30~40%. Shrub layer had the height of 2~6m, and the coverage of 30%, while herb layer had the height 0.2~2m, and the coverage 20-80%. Succession does not occur in the surveyed areas which have high visitor density. Artificially planted sawtooth oak(Quercus acutissima) trees were found to disturb succession and formation of multi-layer vegetation, resulting in the ecologically unstable forest. Therefore, the researcher suggested the strategy of managing the vegetation in the conclusion. This study has the limit in that the plots selected for the survey reflected only part of various trails in the Molundae area. It is necessary to suggest the vegetation management plans by selecting more diverse trail areas in consideration of the visitor density and behaviors, and analyzing the changes in vegetation quantitatively in order to manage the vegetation in urban areas damaged by visitors more effectively.

• Journal of Life Science
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• v.27 no.5
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• pp.567-574
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• 2017

This study is to isolate and identify ${\gamma}$-amino butyric acid (GABA) producing lactic acid bacteria (LAB) from Makgeolii, traditional Korean rice wine and then establish the optimal culture conditions for GABA production. Sixty four LAB from Makgeolli were isolated according to the characteristics of the shape and color of the colony grown on MRS agar plate. The GABA production of the isolated strain cultured in MRS broth contained 1% MSG (mono-sodium glutamate) were determined and evaluated by TLC and HPLC analysis. Strain B-134 was selected for highest GABA production. From the analysis of 16S rRNA and glutamate decarboxylase B (gadB) gene sequences, strain B-134 was tentatively identified as a Lactobacillus plantarum subsp. plantarum B-134. Effects of culture parameters, including glutamic acid level, culture temperature, NaCl level, and pH on GABA production were investigated for culture optimization. The optimum culture condition for GABA production by B-134 were culture temperature of $37^{\circ}C$, pH of 5.7, NaCl content of 0% (w/v) and MSG content of 3% (w/v), which produced 25 mM of GABA during cultivation time of 48 hr. From these results, strain B-134 is expected to be utilized as useful microorganisms for GABA-enriched health beneficial food.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.3
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• pp.284-294
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• 2006

Statement of problem. Proliferation of Candida albicans is primarily within the plaque on the fitting surface of the denture rather than on the inflamed mucosa. Consequently, the treatment of the denture is equally important as treatment of the tissue. Cleansing and disinfection should be efficiently carried-out as the organisms can penetrate into the voids of the acrylic resin and grow in them, from which they can continue to infect and reinfect bearing tissues. Purpose. The purpose of this study was to evaluate the applicability of photocatalytic reaction to eliminate Candida albicans from acrylic resin denture base, and to investigate the anti-fungal effect with various UVA illumination time. Materials and Methods. The specimens were cured by the conventional method following the manufacturer's instruction using thermal polymerized denture base resin (Vertex RS: Dentimex, Netherlands). $TiO_2$ photocatalyst sol(LT), which is able to be coated at normal temperature, was made from the Ti-alkoxide progenitor. The XRD patterns, TEM images and nitrogen absorption ability of the $TiO_2$ photocatalyst sol(LT) were compared with the commercial $TiO_2$ photocatalyst P-25. The experimental specimens were coated with the mixture of the $TiO_2$ photocatalyst sol(LT) and binder material (silane) using dip-coater, and uncoated resin plates were used as the control group. Crystallinity of $TiO_2$ of the specimen was tested by the XRD. Size, shape and chemical compositions were also analyzed using the FE-SEM/ EDS. The angle and methylene blue degradation efsciency were measured for evaluating the photocatalytic activity of the $TiO_2$ film. Finally, the antifungal activity of the specimen was tested. Candida albicans KCTC 7629(1 ml, initial concentration $10^5$ cells/ ml) were applied to the experiment and control group specimens and subsequently two UVA light source with 10W, 353 nm peak emission were illuminated to the specimens from 15cm above. The extracted $2{\mu}l$ of sample was plated on nutrient agar plate ($Bacto^{TM}$ Brain Heart Infusion; BD, USA) with 10 minute intervals for 120 minute, respectively. It was incubated for 24 hours at $37^{\circ}C$ and the colony forming units (CFUs) were then counted. Results. Compared the characteristics of LT photocatalyst with commercial P-25 photocatalyst, LT were shown higher activity than P-25. The LT coated experimental specimen surface had anatase crystal form, less than 20 nm of particle size and wide specific surface area. To evaluate the photocatalytic activity of specimens, methylene blue degradation reaction were used and about 5% of degradation rate were measured after 2 hours. The average contact angle was less than $20^{\circ}$ indicating that the LT photocatalyst had hydrophilicity. In the antifungal activity test for Candida albicans, 0% survival rate were measured within 30 minute after irradiation of UVA light. Conclusion. From the results reported above, it is concluded that the UVA-LT photocatalytic reaction have an antifungal effect on the denture surface Candida albicans, and so that could be applicable to the clinical use as a cleaning method.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1197-1204
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• 2018

Objective: The objective was to characterize the fermentative and microbiological profile of Tifton 85 bermudagrass haylage with different layers of polyethylene film and storage time. Methods: The experimental design consisted of a randomized block design with four and six wrapping layers (100 and 150 microns in total. respectively) allocated in the main plots, through repeated measures analysis (30, 60, and 90 days of storage) with four replicates. Results: The storage time and number of wrapping layers did not show changes in the population of Clostridium and lactic acid bacteria. A decrease was observed in the enterobacteria population with an increase in the storage period in the two wrapping layers studied. Upon opening of the haylage at 30 days, the population of Bacillus was lower in haylages made with six layers of wrapping (3.63 log colony forming units/g). No growth of Listeria sp. or Salmonella sp. was observed during the experimental period. The fungal genera with a greater occurrence were Penicillium sp. and Fusarium sp. The following mycotoxins were not detected: ochratoxin A, fumonisins, and zearalenone. Relative to the organic butyric, propionic, and acetic acids, the haylages presented a low concentration of lactic acid; this may have prevented a drop in the pH, which was high when the silos were opened (5.4). The levels of ammoniacal nitrogen and soluble carbohydrates presented no variation among the number of wrapping layers, with an overall average of 35.55 and 38.04 g/kg. Conclusion: Tifton 85 bermudagrass haylage wrapped with four and six layers presented adequate fermentation and microbiological characteristics in the evaluated periods.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.117-119
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• 2009

Rhizopus soft rot caused by Rhizopus stolonifer occurred on strawberry (Fragaria ${\times}$ ananassa) in the plastic boxes in Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea on April 2008. The infected fruits were rapidly softened, water soaked and finally rotted. The symptoms were mainly occurred through wounds at harvest time. The colony color was white, cottony to brownish black after fully matured and numerous sporangiospores were formed on sporangia. The optimum growth temperature of the fungus was $30^{\circ}C$ on potato dextrose agar. Sporangia were globose or hemispheric shape of white color at initial stage and gradually changed with black color of $82{\sim}195{\mu}m$ in size. Sporangiophores were $12{\sim}25{\mu}m$ in width. Columella were hemispheric in shape, and $70{\sim}92{\mu}m$ in size. Sporangiospores were irregular round or oval in shape, brownish-black in color and $9{\sim}21\;{\times}\;7{\sim}8{\mu}m$ in size. This fungus formed stolones and rhizoid on PDA. On the basis of symptom, mycological characteristics and pathogenicity of the fungus, the causal fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill.