• 약학회지
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• 제45권5호
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• pp.431-436
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• 2001

Antifungal activities of trans-cinnamaldehyde (CA) derivatives including commercial CA derivatives as well as synthesized CA derivatives against various human pathogenic fungi were investigated. Among the derivatives tested, -chlorocinnamaldehyde, $\alpha$-bromocinnamaldehyde and 7-phenyl-2,4,6-heptatrienal were more potent than CA in antifungal activity, $\alpha$-Bromocinnamaldehyde was the most effective in inhibiting the growth of representative fungi of dermatomycosis with minimum inhibitory cocentration(MIC) of 0.61~9.76$\mu\textrm{g}$/ml . In the structure-activity relationship, introduction of the chlorine and bromine group into the C-2 of CA resulted in the decrease of MIC. Derivative with more double bonds exhibited the increase of antifungal activity against various pathogenic fungi.

• Mycobiology
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• 제41권2호
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• pp.67-72
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• 2013

Pathogenic microbes secrete various enzymes with lipolytic activities to facilitate their survival within the host. Lipolytic enzymes include extracellular lipases and phospholipases, and several lines of evidence have suggested that these enzymes contribute to the virulence of pathogenic fungi. Candida albicans and Cryptococcus neoformans are the most commonly isolated human fungal pathogens, and several biochemical and molecular approaches have identified their extracellular lipolytic enzymes. The role of lipases and phospholipases in the virulence of C. albicans has been extensively studied, and these enzymes have been shown to contribute to C. albicans morphological transition, colonization, cytotoxicity, and penetration to the host. While not much is known about the lipases in C. neoformans, the roles of phospholipases in the dissemination of fungal cells in the host and in signaling pathways have been described. Lipolytic enzymes may also influence the survival of the lipophilic cutaneous pathogenic yeast Malassezia species within the host, and an unusually high number of lipase-coding genes may complement the lipid dependency of this fungus. This review briefly describes the current understanding of the lipolytic enzymes in major human fungal pathogens, namely C. albicans, C. neoformans, and Malassezia spp.

• The Plant Pathology Journal
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• 제30권1호
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• pp.102-108
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• 2014

The bacterial strain T-9, which shows strong antifungal activity, is isolated from the soils of Samcheok, Gangwondo and identified as Paenibacillus kribbensis according to morphological and taxonomic characteristics and 16S rRNA gene sequence analysis. The P. kribbensis strain T-9 strongly inhibits the growth of various phytopathogenic fungi including Botrytis cinerea, Colletotricum acutatum, Fusarium oxysporum f. sp. radicis-lycopersici, Magnaporthe oryzae, Phytophthora capsici, Rhizoctonia solani, and Sclerotium cepivorum in vitro. Also, the P. kribbensis strain T-9 exhibited similar or better control effects to plant diseases than in fungicide treatment through in vivo assays. In the 2-year greenhouse experiments, P. kribbensis strain T-9 was highly effective against clubroot. In the 2-year field trials, the P. kribbensis strain T-9 was less effective than the fungicide, but reduced clubroot on Chinese cabbage when compared to the control. The above-described results indicate that the strain T-9 may have the potential as an antagonist to control various phytopathogenic fungi.

• 한국버섯학회지
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• 제8권2호
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• pp.41-50
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• 2010

Mycoviruses have been found in many fungal species including mushrooms. Double-stranded (ds) RNA genomes were common type in mycoviruses, but single-stranded (ss) RNA mycoviruses were also reported in some fungal species. Sequencing analysis using cDNA cloning experiments revealed that mycoviruses can be classified into several different virus families such as Totiviridae, Hypoviridae, Partitiviridae and Barnaviridae etc. Because the nucleotide sequence data that are available in these days are very limited in a number of mycoviruses, the existence of more diverse viral groups in fungi are currently expected. In this review, we selected four different fungal groups, which were considered as the model systems for mycovirus related studies in both plant pathogenic fungi and edible mushroom species, and discussed about their molecular characteristics of diverse mycoviruses. The plant pathogenic fungi introduced here were Cryphonectria parasitica and Helminthosporium victoriae and the edible mushroom species were Agaricus bisporus and Pleurotus ostreatus.

• Mycobiology
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• 제43권4호
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• pp.435-443
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• 2015

Sixty-one endophytic fungus strains with different colony morphologies were isolated from the leaves, stems and roots of Tephrosia purpurea with colonization rates of 66.95%, 37.50%, and 26.92%, respectively. Based on internal transcribed spacer sequence analysis, 61 isolates were classified into 16 genera belonging to 3 classes under the phylum Ascomycota. Of the 61 isolates, 6 (9.84%) exhibited antifungal activity against one or more indicator plant pathogenic fungi according to the dual culture test. Isolate TPL25 had the broadest antifungal spectrum of activity, and isolate TPL35 was active against 5 plant pathogenic fungi. Furthermore, culture filtrates of TPL25 and TPL35 exhibited greater than 80% growth inhibition against Sclerotinia sclerotiorum. We conclude that the endophytic fungal strains TPL25 and TPL35 are promising sources of bioactive compounds.

• Mycobiology
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• 제31권3호
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• pp.179-182
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• 2003

A total of 187 endophytic fungi were isolated from 11 plant species, which were collected from 11 locations in Korea. Their antifungal activities were screened in vivo by antifungal bioassays after they were cultured in potato dextrose broth and rice solid media. Antifungal activity against plant pathogenic fungi such as Magnaporthe grisea(rice blast), Corticium sasaki(rice sheath blight), Botrytis cinerea(tomato gray mold), Phytophthora infestans(tomato late blight), Puccinia recondita(wheat leaf rust), and Blumeria graminis f. sp. hordei(barley powdery mildew) was determined in vivo by observing the inhibition of plant disease development. Twenty(11.7%) endophytic fungi fermentation broths were able to control, by more than 90%, at least one of the six plant diseases tested. Among 187 liquid broths, the F0010 strain isolated from Abies holophylla had the most potent disease control activity; it showed control values of more than 90% against five plant diseases, except for tomato late blight. On the other hand, fourteen(7.5%) solid culture extracts exhibited potent disease control values of more than 90% against one of six plant diseases. The screening results of this study strongly suggested that metabolites of plant endophytic fungi could be good potential sources for screening programs of bioactive natural products.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2005년도 국제학술심포지움 The 44th Annual Meeting of Korean Society for Life Science
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• pp.73-74
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• 2005

• 한국균학회소식:학술대회논문집
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• 한국균학회 2016년도 춘계학술대회 및 임시총회
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• pp.13-13
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• 2016

Insects constitute the largest and most diverse group of animals in the world. They also serve as the hosts or nutrient sources for an immense assemblage of pathogens, parasites, and predators. More than 700 fungal species from 100 genera have adopted an entomopathogenic lifestyle. Although entomopathogenic fungi were studied as only biocontrol agents against a variety of pests in various countries, it has been recently focused their additional roles in nature. They are antagonists to/against plant pathogens, endophytes, and possibly even plant growth promoting agents. The potential antimicrobial effect against fungal plant pathogens by an isolate of entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have been reported since late 1990s, but wasn't reported pathogenicity of the isolate against pests. Later, a Canadian Lecanicillium sp. isolate and L. longisporium isolated from Vertalec$^{(R)}$ showed simultaneous control effect against both aphid and cucumber powder mildew. Therefore, the antimicrobial activities of 342 fungi isolates collected from various regions and conditions in Korea were evaluated against plant pathogenic fungus Botrytis cinerea using dual culture technique on agar plate. As a result, 186 isolates (54.4%) shown the antifungal activity against B. cinerea. The culture filtrates of selected fungi completely suppressed the growth of the microorganisms, indicating that suppression was due to the presence of antimicrobial substances in the culture filtrate. Mode of action of these fungi against insect involves the attachment of conidia to the insect cuticle, followed by germination, cuticle penetration, and internal dissemination throughout the insect. During infection process, secreted enzymes, proteinous toxins, and/or secondary metabolites secreted by entomopathogenic fungi can be used to overcome the host immune system, modify host behavior, and defend host resources. Recently, secondary metabolites isolated from entomopathogenic fungi have been reported as potential bioactive substances. Generally, most of bioactive substances produced by entomopathogenic fungi have reported low molecular weight (lower than 1,000 g/mol) as peptide and, in contrast the high molecular weight fungal bioactive substances are rare. Most substances based on entomopathogenic fungi were shown antimicrobial activity with narrow control ranges. In our study we analyzed the antimicrobial substances having antagonistic effects to B. cinerea. Antimicrobial substances in our fungal culture filtrates showed high thermostability, high stability to proteolytic enzymes, and hydrophilicity and their molecular weights were differed from substance. In conclusion, entomopathogenic fungi showed pathogenicity against insect pests and culture filtrate of the fungi also shown to antimicrobial activity. In the future, we can use the entomopathogenic fungi and its secondary metabolites to control both insect pest control and plant pathogenic fungi simultaneously.

• 대한임상검사과학회지
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• 제48권4호
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• pp.343-347
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• 2016

각질친화성 진균(keratinophilic fungi)은 대부분 토양에 분포하면서 사람이나 동물의 피부에 감염되어 상재균으로 존재하고, 각질에 침입하여 백선이라는 피부질환을 유발하기도 한다. 전세계적으로 광범위하게 분포되어 있으나 발생 양상은 기후나 지리적인 요건 등에 뚜렷한 차이를 보인다. 이 균주들은 피부나 손톱, 모발 등에 풍부한 케라틴을 분해하면서 영양분을 공급받으며 증식한다. 이 논문에서는 우리나라 여름철 휴가지로 가장 많은 인파가 몰리는 해운대를 선택하게 되었으며 매년 많은 사람들이 모이는 해운대 백사장에 피부사상균의 존재와 검출되는 균의 종에 대해 조사하고 고찰하였다. 토양시료는 무작위로 총 100개를 채취하였고 채취된 검체는 hair-baiting technique을 이용하여 분석하였으며 100개 시료 중 21곳의 모래시료에서 23종의 피부사상균이 검출되었다. 검출된 균들은 Microsporum gypseum (43%), Chrysosporium spp. (35%), Trichophyton ajelloi (13%), Microsporum cookie (9%) 순이었다. 본 연구를 통해 많은 사람들이 모이는 해변 모래사장에 다양한 병원성 진균들이 분포함을 확인하였다. 향후 지속적인 자료수집을 통해 각질친화성 피부사상균의 분포 추이를 조사할 수 있을 것으로 사료된다.

• The Plant Pathology Journal
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• 제15권5호
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• pp.280-286
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• 1999

Lichen-forming (LFF) or lichenicolous fungi (LCF) were isolated from the lichens collected at‘Backwoon’mountain area,‘Chiri’mountain area and‘Sorok’island in the southern regions of Korea and were screened for antagonistic efficacy against several phyto-pathogenic fungi. Symbiotic algae-free LFF and LCF were isolated by the following methods: I) discharged spores (ascospores), II) macerated thallus suspension and III) direct use of thallus fragments. Among 58 isolates obtained from 34 lichens, 8 isolates showed antifungal activity against Rhizoctonia solani. Antifungal activities of the strongest antagonistic isolate (LB9810) originated from the thallus of Parmelia quercina lichen were evaluated against 15 phyto-pathogenic fungi. When crude methanol extract of mycelia of the LB8910 isolate was employed at the rate of 0.5% (v/w), fungal growth of Magnaporthe grisea and Rhizoctonia solani was severly and Rhizoctonia solani was severly inhibited as much as approximately 60% compared to control. Growth of various food-borne same extract. The extract was successively partitioned with n-hexane, ethyl acetate and n-butanol. n-Hexane fraction displayed the strongest antifungal activities against R. solani. The LB9810 isolate was finally identified as Fusarium equiseti (Corda) Sacc., which has not been reported as LFF or LCF yet. Therefore, it is very likely that F. equiseti isolated it the study was originated from the contaminants associated with thallus fragments rather than from LFF or LCF.