• Research in Plant Disease
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• v.8 no.4
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• pp.239-244
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• 2002

Among 34 isolates of Colletotrichum spp., 20 from red pepper and 14 from apple, only one isolate 2001-45 was identified as the isolate resistant to sterol biosynthesis inhibiting fungicides. EC$_{50}$ values of the isolate 2001-45 were 153.5, 42.7, 34.0, and 17.1 $\mu\textrm{g}$/ml for myclobutanil, tebuconazole, hexaconazole and nuarimol, respectively, The resistance factor of the isolate 2001-45 against the other isolate 2001-44 to 4 above fungicides was ranged from 17 to 57. However, EC$_{50}$ value of the 2001-45 for prochloraz was 0.07 $\mu\textrm{g}$/ml, which was lower than those of the 2001-44 and the isolate JC24. For the fitness test of the 2001-45, mycelial growth, sporulation on PDA and pathogenicity on fruits were investigated. No difference in mycelial growth was found between 2001-45 and 2001-44, but great difference in sporulation. No symptom was developed by 2001-45 even by wound inoculation of pepper fruit. Therefore, this study indicated that the isolate 2001-45 was inferior to the other isolates in the fitness, although the isolate 2001-45 was highly resistant to sterol biosynthesis inhibiting fungicides.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.602-603
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• 2006

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.554-555
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• 2006

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1170-1172
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• 2009

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.13-13
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• 2015

Rice blast fungus, Magnaporthe oryzae, is the most destructive pathogen of rice in the world. This fungus has a biotrophic phase early in infection and switches to a necrotrophic lifestyle after host cell death. During the biotrophic phase, the fungus competes with host for nutrients and oxygen. Continuous uptake of oxygen is essential for successful establishment of blast disease of this pathogen. Here, we report transcriptional responses of the fungus to oxygen limitation. Transcriptome analysis using RNA-Seq identified 1,047 up-regulated genes in response to hypoxia. Those genes were involved in mycelial development, sterol biosynthesis, and metal ion transport based on hierarchical GO terms and well-conserved among three different fungal species. In addition, null mutants of three hypoxia-responsive genes were generated and tested for their roles on fungal development and pathogenicity. The mutants for a sterol regulatory element-binding protein gene, MoSRE1, and C4 methyl sterol oxidase gene, ERG25, exhibited increased sensitivity to hypoxia-mimetic agent, increased conidiation, and delayed invasive growth within host cells, suggesting important roles in fungal development. However, such defects did not cause any significant decrease in disease severity. The other null mutant for alcohol dehydrogenase gene, MoADH1, showed no defect in the hypoxia-mimic condition and fungal development. Taken together, this comprehensive transcriptional profiling in response to a hypoxia condition with experimental validations would provide new insights on fungal development and pathogenicity in plant pathogenic fungi.

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.84.2-84.2
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• 2006

• Korean Journal of Pharmacognosy
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• v.13 no.1
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• pp.39-42
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• 1982

Spiraea prunifolia Sieb. et. Zucc. var. simpliciflora Nakai (Rosaceae) is distributed in Korea, and used as a folk medicine for antipyretic, antimalarial and emetic. Sterols were obtained from the methanolic extract of the root of above plant. The composition of sterols are campesterol and ${\beta}-sitosterol$ which has been determined by gaschromatographic analysis.

• Journal of Applied Biological Chemistry
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• v.53 no.2
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• pp.77-81
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• 2010

The seed of cowpea (Vigna sinensis K.) was extracted with 80% aqueous methanol (MeOH). And the concentrated extract was partitioned with ethyl acetate (EtOAc), n-butanol (n-BuOH) and $H_2O$, successively. The repeated silica gel and octadecyl silica gel (ODS) column chromatographic separations for the EtOAc and n-BuOH fractions led to isolation of four sterols. And the chemical structures of the compounds were determined as a mixture of stigmasterol and $\beta$-sitosterol with the ratio of 4 to 3 (1), 7-ketositosterol (2), and stigmasterol 3-O-$\beta$D-glucopyranoside (3) from the interpretation of spectroscopic data including nuclear magnetic resonance (NMR) spectrum metric, mass (MS) spectrum metric and infrared (IR) spectroscope. This study reports the first isolation of $\beta$-sitosterol, 7-ketositosterol, and stigmasterol 3-O-$\beta$-D-glucopyranoside from the seed of Vigna sinensis K. In addition, compound 2, 7-ketositosterol, is rarely occurred in natural source including plant.

• Korean Journal of Pharmacognosy
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• v.40 no.4
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• pp.319-325
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• 2009

Twelve compounds were isolated from the 70% ethanol extract of Lonicera Caulis (Caprifoliaceae) and their structures were identified as six triterpenoids [(24S)-cycloart-25-en-$3{\beta}$,24-diol (1), pomolic acid (7), ursolic acid (8), euscaphic acid (9), hederagenin (10), and 23-hydroxytormentic acid (12)] and six sterols [obtusifoliol (2), gramisterol (3), citrostadienol (4), ${\beta}$-sitosterol (5), ergosterol peroxide (6) and ${\beta}$-sitosterol glucoside (11)]. The chemical structures of these compounds were identified on the basis of spectroscopic methods and comparison with literature values. All the compounds were isolated from this plant parts for the first time.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.140-144
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• 2006

Sajabalssuk (Artemisia herba) was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc and n-BuOH fractions, four sterols were isolated through the repeated silica gel and ODS column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the sterols were determined as ${\beta}-sitosterol$ (1), ergosterol peroxide (2), stigmasterol (3) and daucosterol (4). They were the first to be isolated from Sajabalssuk (Artemisia herba).