• Research in Plant Disease
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• v.12 no.3
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• pp.290-293
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• 2006

A fruit rot of sweet persimmon(Diospyros kaki cv. 'Fuyu') that infected with blue mold was found during the storage and transport in Jinju Gyeongnam Province, Korea. Fruit surfaces that infected with the fungus were formed water soaked lesion at first then gradually colonized with the fungus and formed mycelial mats. From the point of infection, fruits become sunken and mostly ruptured. The pathogenic fungus was isolated from infected fruits and cultured on potato dextrose agar. The colonies of the pathogenic fungi were white at frist then became greyish green on malt extract agar. Conidia were ellipsoidal and $2.6{\sim}3.8{\times}2.4{\sim}3.8{\mu}m$ in size. Phialides were ampulliform, verticilate of 3-7, $8.0{\sim}9.2{\times}2.0{\sim}3.0{\mu}m$ in size. Metulae were verticils of 2-4, smooth, $9.0{\sim}12.6{\times}3.0{\sim}4.6{\mu}m$ in size. Ramuli were groups 1-3, smooth, $11.0{\sim}17.6{\times}2.3{\sim}3.0{\mu}m$ in size. Rami were groups 1-2, $7.5{\sim}32.6{\times}2.6{\sim}4.2{\mu}m$ in size. Stipes were septate, smooth, thin walled, $56{\sim}302{\times}2.8{\sim}4.0{\mu}m$ in size. Penicilli were mostly quaterverticillate. Based on the cultural and mycological characteristics as well as pathogenicity test on host plants, the fungus was identified as Penicillium expansum. This is the first report on the blue mold of sweet persimmon(Diospyros kaki) caused by P. expansum in Korea.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.33-33
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• 2018

Air-borne plant pathogenic fungus Fusarium graminearum and seed-borne plant pathogenic bacterium Burkholderia glumae are cause similar disease symptoms in rice heads. Here we showed that two pathogens frequently co-isolated in rice heads and F. graminearum is resistant to toxoflavin produced by B. glumae while other fungal genera are sensitive to the toxin. We have tried to clarify the resistant mechanism of F. graminearum against toxoflavin and the ecological reason of co-existence of the two pathogens in rice. We found that F. graminearum carries resistance to toxoflavin as accumulating lipid in fungal cells. Co-cultivation of two pathogens resulted in increased conidia and enhanced chemical attraction and attachment of the bacterial cells to the fungal conidia. Bacteria physically attached to fungal conidia, which protected bacterium cells from UV light and allowed disease dispersal. Chemotaxis analysis showed that bacterial cells moved toward the fungal exudation compared to a control. Even enhanced the production of phytotoxic trichothecene by the fungal under presence of toxoflavin and disease severity on rice heads was significantly increased by co-inoculation rather than single inoculation. This study suggested that the undisclosed potentiality of air-born infection of bacteria using the fungal spores for survival and dispersal.

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.292-296
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• 2003

Effects of aybusculayr mycorrhizal fungus (aMF), Glomus manihot, on plant growth and nutrient uptake on pepper (Capsicum annuum L.) seedlings were evaluated in the nursery experiment. Five different strains of pepper, Chungok, Shingang, Manitta, Gonggongchil, and Shintaeyang, were used in this study. Total fresh weight, nutrient (nitrogen, phosphate and potassium) uptake were increased in all strains inoculated with G. manihot alone and G. manihot and rock phosphate over control at 2 weeks after seeding. Plant weight and phosphate uptake in plants treated with AMF were significantly higher (P< 0.05) than those of control at 6 weeks after seeding. The treatment with G. manihot and rock phosphate gave better plant performance than the treatment with G. manihot alone at 6 weeks after seeding. The lengths of pathogenic symptom on pepper by Phytophthora capsici were reduced significantly by the inoculation of G. manihot spores, Therefore, it would be expected that AMF can be used as the biocontrol agent on pathogens in pepper.

• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.950-956
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• 2002

The antitumor activity of the insect pathogenic fungus Paecilomyces japonica has been attributed to apoptotic cell death. However, the mechanism underlying the induced apoptosis has not yet been elucidated. In this study, we for the first time show that mitochondria-dependent caspase-3 activation were associated with the apoptotic activity of P. japonica in human acute leukemia Jurkat T cells. When Jurkat T cells were treated with the ethyl acetate extract of P japonica at concentrations ranging from $2-6{\mu}g/ml$, apoptotic cell death. accompanied by several biochemical events such as caspase-9 activation, caspase-3 activation, degradation of poly (ADP-ribose) polymerase (PARP), and apoptotic DNA fragmentation, was induced in a dose-dependent manner. In addition, the release of cytochrome c from mitochondria was detected. Under these conditions, the expression of Fas and Fas-ligand (FasL) remained unchanged. Ethyl acetate extract-induced mitochondrial cytochrome c release, caspase-3 activation, PARP cleavage, and apoptotic DNA fragmentation were suppressed by the ectopic expression of Bcl-2, which is known to block mitochondrial cytochrorme c release. Accordingly, these results demonstrate that P. japonica-induced apoptotic cell death is mediated by a cytochrome c-dependent caspase-3 activation pathway that can be interrupted by Bcl-2.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.6
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• pp.1184-1189
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• 2002

Allii sativi Bulbus(garlic) have been shown to possess medicinal value, in particular, antimicrobial activity. In this study, we compared the efficacy on some pathogenic bacteria and fungus among several different extracts(water, hexane, ethyl acetate, methanol, chloroform) of Allii sativi Bulbus. Animal pathogenic bacteria and fungus(S. gallinarium: KCTC 2441, S. flexneri: KCTC 2361, E. cloacae: KCTC 2006, K. pneumonia: KCTC 2208, C. albicans: KCTC 1940) were used to test by measurement of minimum inhibitory concentrations(MIC) and disc diffusion. Allii sativi Bulbus were cut and mixed with water at 37℃ about 24 h and filtered, and several different solvents(hexane, chloroform, ethyl acetate, methanol) were respectively added to separate the fraction of each solvent. The antimicrobial(bacteriocidal) and antifungal effect were apparently shown from water extract, hexane and ethyl acetate extract against using strains(Staphylococcus gallinarium, Shigella flexneri, Enterobacter doacae, Klebsiella pneumonia, Candida albicans). Especially, the water extract showed the superior efficacy. And the clear zone size of water extract (11～27 mm) was greater than that of gentamycin, hexane extract and ethyl acetate extract against S. gallinarium. S. flexneri, K. pneumonia and C. albicans. Minimum inhibitory concentrations(MIC) of water extract appeared to around 2.0～7.5 ㎎/㎖ against S. gallinarium, S. flexneri, E. cloacae and K. pneumonia. The greater activity was shown by water extract because the MIC of water extract for C. albicans observed in very low concentration(<1.0 ㎎/㎖) compared to hexane(5.0 ㎎/㎖) and ethyl acetate(10.0 ㎎/㎖). Therefore, these results exhibited that water extract of Allii sativi Bulbus have stronger antimicrobial activity than hexane and ethyl acetate extract, and may be useful as topical medicine of superficial infections causing C. albicans as well as antifungal agents.

• Molecules and Cells
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• v.42 no.1
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• pp.56-66
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• 2019

Histidine triad nucleotide-binding protein (HINT) is a member of the histidine triad (HIT) superfamily, which has hydrolase activity owing to a histidine triad motif. The HIT superfamily can be divided to five classes with functions in galactose metabolism, DNA repair, and tumor suppression. HINTs are highly conserved from archaea to humans and function as tumor suppressors, translation regulators, and neuropathy inhibitors. Although the structures of HINT proteins from various species have been reported, limited structural information is available for fungal species. Here, to elucidate the structural features and functional diversity of HINTs, we determined the crystal structure of HINT from the pathogenic fungus Candida albicans (CaHINT) in complex with zinc ions at a resolution of $2.5{\AA}$. Based on structural comparisons, the monomer of CaHINT overlaid best with HINT protein from the protozoal species Leishmania major. Additionally, structural comparisons with human HINT revealed an additional helix at the C-terminus of CaHINT. Interestingly, the extended C-terminal helix interacted with the N-terminal loop (${\alpha}1-{\beta}1$) and with the ${\alpha}3$ helix, which appeared to stabilize the dimerization of CaHINT. In the C-terminal region, structural and sequence comparisons showed strong relationships among 19 diverse species from archea to humans, suggesting early separation in the course of evolution. Further studies are required to address the functional significance of variations in the C-terminal region. This structural analysis of CaHINT provided important insights into the molecular aspects of evolution within the HIT superfamily.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.74-81
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• 1984

The experiments were conducted to study the distribution of wilt of strawberry caused by Fusarium in Korea, the characters of the causal fnngus and its control. The results obtained are summarized as follows. 1. Wilt of strawberry has been found in Gimhae and Samrangjin, Gyeongnam province a few years ago. This disease has been spreading year after year, and observed on farms in most of the strawberry-growing areas in Korea. 2. The fungus was isolated frequently from the crowns and petioles of diseased straw berry plants, and the fungus belonging to Fusariun oxysporum in terms of the morphological characteristics of macroconidia, microconidia, chlamydospore and conidiophore on V-8 Agar. 3. The macroconidia formation of the fungus varied remarkably with the Isolates and kinds of medium tested. However. all isolates abundantly produced macroconidia on V-8 Agar. 4. The cross-inoculation tests with several forma specialis of F. oxysporum to cucumber, tomato, watermelon, luffa, cabbage, melon and strawberry were carried out. The isolates from strawberry viz. Kodama's F. oxysporum f. sp. fragariae and S-1 of the authors were pathogenic to only strawberry. The fungus was also similar in morphology and symptoms to Kodama's and Winks' isolate of F. oxysporum f. sp. fragariae. Therefore, the fungus is identified as Fusarium oxysporum Schl. f. sp. fragariae Winks & Williams. 5. The most effective fungicides were Benomyl and Homai for inhibiting sporulation and mycelial growth of the fungus. 6 The cultivar Kurumae 35, Himiko, Senga gigana and Daehak I were resistant, whereas Hokowase, Instiate Z4, Juspa, Puget beauty and Marshall were susceptible to the fungus with artificial inoculation.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.31-38
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• 1998

Since 1990, destructive yellow rots on Ganoderma lucidum caused by a soilborne fungus have been occurred in major cultivation areas of Korea. Incidences of the disease were 61% in Chulwon and 94% in Kanghwa area where the mushroom has been cultivated for 10 years, whereas the disease has not been found yet in new cultivation areas such as Moonkyung and Hongsung. when severely infected, inner tissues of bed-logs showed severe yellow and fruiting bodies of the mushroom was not produced. Infected tissues of bed-logs were readily distinguished from those of healthy ones by a distinctive brown border line. When the disease progressed, mycelia of Ganoderma lucidum were totally destroyed, and abundant ascocarps of the pathogen were formed inside the tissues of bed-logs showing yellowish green. The fungus derived from a single ascospore strongly lysed mycelia of Ganoderma lucidum growing on bottle media, and non-volatile components secreted by the pathogen were also highly inhibitory to mycelial growth of the mushroom fungus. The pathogen was identified as Arthrographis cuboidea based on its distinctive cultural and morphological characters. The fungus produced arthroconidia and unbrached conidiophores. The width of fungal conidia was distinctively wide as compared with the length. Colonies of the fungi were pale yellow to yellowish green on agar media. As a causal pathogen of yellow rot of Ganoderma lucidum., this fungus has not been reported yet in Korea.

• Journal of dental hygiene science
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• v.18 no.1
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• pp.18-23
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• 2018

Propolis has been used as a natural remedy in folk medicine worldwide. The antibacterial, antiviral, antifungal, and antiprotozoal aspects of its antimicrobial properties have been widely investigated. However, few studies focused on its applications in dentistry. Many dental diseases are related to various microorganisms in the oral cavity. In this study, we assessed the antimicrobial activity of Korean propolis extract, collected from 6 different regions, on oral pathogenic microorganisms. The propolis samples, collected from 6 different regions (P1: Uijeongbu, P2: Ansan, P3: Hongcheon, P4: Iksan, P5: Gwangju, and P6: Sangju), were dissolved in ethanol at two different concentrations (10 and 50 mg/ml). Three oral bacteria (Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis) and one fungus (Candida albicans) were activated in general broth for 24 hours. Microorganisms were diluted and spread onto agar plates, onto which sterilized 6 mm filter papers with or without each propolis sample were placed. After 24 hours of incubation, clear zones of inhibition were observed. All tests were performed in triplicate. The propolis samples showed significant antibacterial and antifungal activity on oral pathogenic microorganisms; in addition, low-concentration groups showed outstanding antimicrobial efficacy on the 4 different microorganisms. Among the samples, P6 had significantly higher antibacterial activity than that of the others against three different bacteria. In particular, a high concentration of P6 showed a significant antifungal effect. In conclusion, we confirmed that Korean propolis has an inhibitory effect on oral pathogenic bacteria and fungi. Therefore, we suggest the possibility of developing oral medicine and oral care products based on Korean propolis.

• Research in Plant Disease
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• v.16 no.3
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• pp.323-325
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• 2010

The stem rot of sunflower (Helianthus annuus) occurred sporadically in the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services, on September, 2009. The infected plants were wilted and water-soaked brown spots were formed on the stem, than infected stems were mostly died. White mycelial mats were spread over lesions, and then sclerotia were formed on stem and near soil line. The sclerotia were globoid in shape, 1~3 mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$ and the hyphal width was $4{\sim}8\;{\mu}m$. The typical clamp connections were observed in the hyphae of the pathogenic fungus. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report on the stem rot of sunflower by S. rolfsii in Korea.