• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.27-36
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• 1996

The aim of the present research program was to identify and develop strains of actinomycetes producing antifungal antibiotics which inhibit cell wall biosynthesis. 860 strains of Actinomycetes were isolated from various soil samples. Three isolates, EMS4, EMP22, and L234 were selected as the strains producing antifungal antibiotics inducing abnormal morphology against Penicillium cyclopium, Cryptococcus laurentii, and Aspergillus flavus, respectively. Taxonomic unit characters of the strains were tested and the data were analyzed numerically using TAXON program. EMS4, EMP22, and L234 were indentified to be a member of Streptomyces lavendulae, Streptomyces willmorei, and Streptomyces aburaviensis, respectively.

• Journal of Microbiology and Biotechnology
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• v.5 no.6
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• pp.324-334
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• 1995

The actinomycete strain A 11 was antagonistic to plant pathogenic fungi Phytophthora capsid and Magnaporthe grisea. Based on the diaminopimelic acid (DAP) type and morphological characteristics examined by scanning electron microscopy, the strain A 11 was confirmed to belong to the genus Streptomyces. Based on Willcox probability and similarity level, the strain A 11 was numerically identified as Streptomyces flaveus using TAXON program of Ward and Goodfellow. Antibiotic production of S. flaveus strain A 11 was most favorable when cultured on glycerol yeast extract peptone (GYP) agar for 20 days at $28^{\circ}C$. The crude antibiotics from solid GYP agar cultures of the strain A 11 were most effective against Phytophthora capsici and Sclerotinia sclerotiorum among the fungi tested. Antifungal activity of the antibiotics against Alternaria solani, Botryosphaeria dothidea, Cercospora capsici, Magnaporthe grisea, and Rhizoctonia solani was somewhat high, whereas Colletotrichum gloeosporioides and Fusarium oxysporum f. sp. cucumerinum were rarely inhibited even at high concentrations.

• Natural Product Sciences
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• v.16 no.3
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• pp.175-179
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• 2010

The present study aimed to assess the antifungal properties of the essential oil fraction from Ligusticum chuanxiong (Umbelliferae) and its components against five clinically important Aspergillus species. The essential oil fraction was extracted from the underground parts of the plant by steam distillation, and its main components, namely, Z-ligustilide, butylidene phthalide, and p-cresol were isolated by column chromatography. The antifungal activities of the essential oils were evaluated by the broth dilution method. Both the total essential oil fraction of L. chuanxiong and its components showed significant anti-Aspergillus activity against all five tested strains with MICs between 62.5 and 250 ${\mu}g$/ml, respectively. In a checkerboard microtiter assay, the combination of antibiotics, itraconazole with the essential oil fraction of L. chuanxiong or its main components exhibited synergistic or additive, and in some cases indifferent, effects against the tested Aspergillus species, resulting in FICIs (fractional inhibiting concentration indices) ranging from 0.12 to 2, while the combination of antibiotics, amphothericin B with L. chuanxiong essential oils mostly showed antagonistic effects.

• Microbiology and Biotechnology Letters
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• v.23 no.2
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• pp.170-177
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• 1995

To search and develop the compounds exhibiting antifungal activities against the mycelial phase of Candida albicans, approximately 2,900 microorganisms isolated from soil were examined for antifungal activity. Among them, a strain with preferential activity against the mycelial phase of Candida albicans was isolated and identified as Streptomyces sp. A393. Isolation and purification of compounds A393 showing antifungal activity against the mycelial phase of C. albicans were performed using XAD-7 column chromatography, silica gel chromatography, preparative thin- layer silica gel chromatography, and HPLC. The molecular weights of compounds isolated from Streptomyces sp. A393 were determined as 774, 790, 804 and 820. These compounds appeared to have a structure of macrolide antibiotics, oligomycin A, B, C and E. Especially, oligomycin E, which is formerly reported to have no antifungal activity, showed antifungal activity against the mycelial phase of Candida albicans.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.238-242
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• 2004

Antifungal agents, flavofungin and fungichromin were isolated from the fermentation culture broth of a Streptomyces sp. SKM338. Biological evaluation of these antibiotics indicated that the compounds possesses broad spectrum antifungal activity against various pathogens. Especially, these compounds inhibited throughly growth of Didymella bryoniae, caused Gummy stem blight of melons, occurs in the southeastern Korea. Inhibition of this pathogen may be prevented from directly reducing both pre- and post-harvest yields.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.212-215
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• 2004

In order to develop a biocontrol agent that can effectively control Fusarium wilt on Cymbidium genus, the effectiveness of antagonistic microbes against the cause pathogen was screened. The selected microbe showed a broad spectrum of antifungal activity, and the culture broth of this microbe had better preventive effect on Fusarium wilt than the commercial chemical agent in the pot assay. This isolated strain, GBA-12, was identified as Streptomyces kasugaensis, and the antifungal substance was purified from a broth culture of GBA-12. This purified substance was identified as a polyene macrolide (YS-822A) that was newly discovered from Streptomyces kasugaensis, and it exhibited antifungal activity against several phytopathogenic fungi.

• 한국균학회소식:학술대회논문집
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• 2009.10a
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• pp.57-59
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• 2009

• Mycobiology
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• v.37 no.2
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• pp.114-120
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• 2009

Streptomyces albidoflavus C247 was isolated from the soil of the Gyeongsan golf course in Korea. Physiological, biochemical and 16S rDNA gene sequence analysis strongly suggested that the isolate belonged to Streptomyces albidoflavus. Preliminary screening revealed that the isolate was active against fungi and bacteria. Self-directing optimization was employed to determine the best combination of parameters such as carbon and nitrogen source, pH and temperature. Nutritional and culture conditions for the production of antibiotics by this organism under shake-flask conditions were also optimized. Maltose (5%) and soytone (5%) were found to be the best carbon and nitrogen sources for the production of antibiotics by S. albidoflavus C247. Additionally, 62.89% mycelial growth inhibition was achieved when the organism was cultured at $30^{\circ}C$ and pH 6.5. Ethyl acetate (EtOAc) was the best extraction solvent for the isolation of the antibiotics, and 100 ${mu}$/ml of EtOAc extract was found to inhibit 60.27% of the mycelial growth of Rhizoctonia solani AG2-2(IV) when the poison plate diffusion method was conducted.

• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.564-569
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• 1993

AF-001A is a novel antifungal cyclic glyco-peptise isolated from Pseudomonas cepacia AF6008. AF-001A is a mixture of AF-011A1 and AF-001A2. Each compound contains glycine(1), serine(2), asparagine(1), 2,4-diaminobutyric acid(1), beta-hydroxytyrosine(1), xylose(1) and a methylene chain amino acid(1). Additionally, A1 contains one beta-hydroxyasparagine that is replaced with as asparagine in A2. AF-011A showed high in vitro antifungal activity against various animal and plant pathogenic fungi and caused no irritation on the skin of rabbits.

• The Korean Journal of Mycology
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• v.23 no.1 s.72
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• pp.14-27
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• 1995

For the searching of antibiotics in the mushroom, we studied on the screening of antiyeast and antifungal components. The powder of fruiting body of each mushroom was extracted with petroleum ether, 80% ethanol, and distilled water in that order, respectively. The antifungal activity of each extract from 32 different mushrooms were tested. The petroleum ether or ethanol extracts from fruiting bodies of Boletus auripes, Leccinum extremiorientale, Gomphus floccosus, Phaeolus schweinitzii, Pycnoporus cinnabarinus and Marasmius maximus showed antiyeast activities. The ethanol extract of Gyrophora esculenta showed an antiyeast activity against Cryptococcus neoformans, and its minimal inhibitory concentration (MIC) was $600\;{\mu}g/ml$. The petroleum ether or ethanol extracts from fruiting bodies of Amanita citrina, Leccinum extremiorientale, Gomphus floccosus, Phaeolus schweinitzii, Pycnoporus cinnabarinus, Marasmius maximus and Gyrophora esculenta showed antifungal activities. The ethanol extract of Gomphus floccoscus showed an antifungal activity against Microsporum gypseum, and its MIC was $1,000\;{\mu}g/ml$. The ethanol extract of Gyrophora esculenta showed antifungal activities against Trichophyton mentagrophytes, Microsporum gypseum and Pyricularia oryzae, and theirs MIC were $300\;{\mu}g/ml,\;600\;{\mu}g/ml\;and\;600\;{\mu}g/ml$, respectively. The petroleum ether extract of Gyrophrora esculenta also showed an antifungal activity against Microsporum gypseum, and its MIC was $300\;{\mu}g/ml$.