• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.111-111
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• 2003

Several fungal isolates were isolated from diseased monochoria(Monochoria vaginalis, weed of paddy field), which has an resistance to sulfonyl urea(S.U.) herbicide, and were evaluated in the laboratory and greenhouse as potential mycoherbicide. Eight fungi, Alternaria sp., Colletotrichum sp., Curvularia sp., Paenicillium sp and etc. were observed in the isolates. Pathogenicity testing were done on the monochorias in the greenhouse. Monochorias were inoculated with suspensions containing conidia of each isolate at the rates of 1.0 ${\times}$ 10$\^$5/ conidia/ml and 0.1％ Tween 80 with hand-gun sprayer. Curvularia sp. and an unidentified fungal isolate caused 90-95％ mortality on the monochorias 15∼20 days after inoculation. However the other isolates induced slight symptom of disease on the monochorias. In the early stage of disease development sun-burn appearance was shown at the infected site and the last infected leaves and stems were withered to death. Subsequently the pathogenicity on the rice was evaluated with above two effective isolates. From the test an unidentified isolate showed pathogenicity on the rice but Curvularia sp., named as DBB2003, didn't. Now the mass production and formulation using Curvularia sp. DBB2003 are in progress and the field test will be followed. Combination product with Curvularia sp. DBB2003 and chemical herbicide will be more effect to control the monochoria resisted on S.U. herbicide and need to be further tested.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.118-124
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• 2008

Skin sooty dapple disease, a fungal disease that lowers Asian pear fruit quality, has emerged recently in Korea but has not yet been thoroughly characterized. This disease affects the surface of fruit, leaves, and young shoots of the Asian pear, typically appearing as a dark or pale black dapple on the fruit surface. The disease initiates on the fruit with small circular lesions that become bigger, eventually spreading to form large circular or indefinite lesions. Sparse dark or flourishing white-greyish aerial mycelia and appearance of a dark or pale black dapple on the fruit surface are typical signs of this disease. The disease was severe during cold storage of the Niitaka and Chuhwangbae varieties, but more limited on the Gamcheonbae and Hwangkeumbae varieties. To identify causal pathogens, 123 fungal isolates were obtained from lesions. The fungi that caused typical skin sooty dapple disease symptoms in our bioassay were identified. Based on their morphological characteristics, 74% of the isolates were Cladosporium sp. and 5-7 % of the isolates were Leptosphaerulina sp., Tripospermum sp., or Tilletiopsis sp. None of the isolates caused severe soft rot by injection to a wound plug, but some of the Cladosporium sp. isolates caused mild maceration. Therefore this microbiol complex cannot account for the soft rot also observed in stored fruits. The high frequency of isolation of Cladosporium sp. from disease tissues and bioassay on pear fruit surface suggest that Cladosporium sp. could be a major pathogen in the microbial complex associated with skin sooty dapple disease of the Asian pear in Korea.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.52-57
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• 2008

Twenty isolates of Bacillus spp. obtained from livestock manure composts and cotton-waste composts were tested for in vitro antagonistic effects against soilborne plant pathogenic fungi, Fusarium oxysporum, Phytophthora capsici, Rhizoctonia solani AG-4, and Sclerotinia sclerotiorum. Seven isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of F. oxysporum tested. The bacterial isolate RM43 was the most effective to inhibit the mycelial growth of the fungal isolates. Twelve isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of P. capsici tested. The bacterial isolates M34 and M47 were very effective to inhibit the mycelial growth of the fungal isolates. Thirteen isolates of Bacillus spp. had antagonistic effects on mycelial growth of all the isolates of R. solani AG-4 tested. The bacterial isolates M27 and M75 were very effective to inhibit the mycelial growth of the fungal isolates. Fourteen isolates of Bacillus sp. had antagonistic effects on mycelial growth of all the isolates of S. sclerotiorum tested. The bacterial isolates M49 and M75 were very effective to inhibit the mycelial growth of the fungal isolates. The antagonistic effects of most Bacillus spp. isolates against the isolates of the four fungi differed depending on the fungal species and the isolates of each fungus. The bacterial isolates M27 and M75 were the most effective to inhibit the mycelial growth of all four fungi.

• Mycobiology
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• v.39 no.3
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• pp.206-218
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• 2011

The seed-borne mycoflora of sorghum and foxtail millet collected from different growing areas in South Korea were isolated and taxonomically identified using dry inspection, standard blotter and the agar plate method. We investigated the in vitro and in vitro germination rates of disinfected and non-disinfected seeds of sorghum and foxtail millet using sterilized and unsterilized soil. The percent recovery of seed-borne mycoflora from the seed components of sorghum and foxtail millet seeds was determined and an infection experiment using the dominant species was evaluated for seedling emergence and mortality. A higher number of seed-borne fungi was observed in sorghum compared to that of foxtail millet. Eighteen fungal genera with 34 fungal species were identified from the seeds of sorghum and 13 genera with 22 species were identified from the seeds of foxtail millet. Five dominant species such as Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme and Phoma sp. were recorded as seed-borne mycoflora in sorghum and 4 dominant species (Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme) were observed in foxtail millet. The in vitro and in vitro germination rates were higher using disinfected seeds and sterilized soil. More seed-borne fungi were recovered from the pericarp compared to the endosperm and seed embryo. The percent recovery of seed-borne fungi ranged from 2.22% to 60.0%, and Alternaria alternata, Curvularia lunata and 4 species of Fusarium were isolated from the endosperm and embryo of sorghum and foxtail millet. Inoculation of the dominant seed-borne fungi showed considerable mortality of seedlings. All the transmitted seed-borne fungi might well be a primary source of infection of sorghum and foxtail millet crops.

• Korean Journal of Environmental Biology
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• v.20 no.3
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• pp.237-244
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• 2002

To analyze proteins related to antifungal activity, SAR01 strain was isolated from seaweed and identified as Streptomyces sp. from the result of FAME (fatty acid methyl ester) analysis. The isolated strain had antifungal activities against T species of plant pathogenic fungi. Antifungal activity deficient mutant (SAR 535) of Streptomyces sp. SAR01 was induced by gamma radiation $(^{60}Co,\;5kGy)$. By 2 D electrophoresis analysis, 6 protein spots were found in wild strain (SAR01) but these spots disappeared in mutant strain (SAR535). Among them, 5 proteins showed similarities to heat shock protein 70(HSP70), Fe-containing superoxide dismutase II (Fe- SODII), ribosome recycling factor (RRF), 10 kDa chnperonin (GroES) and inorganic pyrophosphatase (PPAse), respectively. It suggested that the above 6 proteins could be closely related to the antifungal activity of Streptomyces sp. SAR01.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.2
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• pp.95-112
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• 1998

For the effective disposal of organic food wastes, we seleted 4 strains of microorganism from 186 microbial candidate via enzyme activity test, salt tolerance, food decomposition rate, stability and safety of strains. The identity of these 4 strains are as follows : Fungi is Rhizopus sp., yeasts are Galactomyces sp., Pichia sp. and Hyphopichia sp., In the 50L fermenter scale, we tested various fermenting factor for the optimization of conditions of food waste decomposition using 4 selected strains. The optimum fomenting conditions were as follows : BIO-CHIP Volume 25-30 L, BIO CHIP size 2.0-6.0mm, air flow 200-280L/min, mixing intensity 2-4rpm, temperature $30-45^{\circ}C$. In these fermenting conditions, the efficiency of decomposition(rate of weight loss of food wastes) were 93%. Also the quality of fermenting output were assayed at the basis of fertilizer, and the results were as good as general compost.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.333-338
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• 2012

Lichens are a symbiosis between fungi, algae and cyanobacteria. Our group recently studied the antioxidant properties of some bacterial species isolated from Arctic lichens and we confirmed that they possess high antioxidant activities. In this paper, we investigated the antioxidant capacity of 5 microorganisms newly isolated from 4 Arctic lichen species, Cladonia sp., Sterocaulon sp., Umbilicaria sp. and Cetraria sp., using various solvent extractions. We carried out 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2'-azino-bis(3-ethyl benzothiazoline-6-sulphonic acid) (ABTS) free radical scavenging activity test and ferric reducing antioxidant power (FRAP) assay. Also total phenolic and flavonoid content assays were performed. Among the bacterial culture extracts of the tested lichen-microorganisms, ethyl acetate extracts of Burkholderia sordidicola S5-B(T) had not only a high antioxidant activity (72.9%) when compared with the ascorbic acid used as the control (51.3%) in the DPPH assay, but also a high amount of phenolic content as well as flavonoid content. As a result, these lichen-microorganisms may be potentially useful sources of natural antioxidants.

• Journal of the Korean Applied Science and Technology
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• v.27 no.4
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• pp.501-507
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• 2010

In this study, we evaluate the anti-microbiological activity of paraben in eye shadows that are composed of pigments and oil binders using various analytical methods and microbiological tests. Paraben does not show the microbiological activity properly when it was used with Nylon SP$^{(R)}$ 10, Talc RF SSA$^{(R)}$, OMC Talc AS$^{(R)}$ and $BaSO_4$. In the test of fungi, Nylon SP$^{(R)}$ 10 causes the decrease of microbiological activity regardless of the type of oil binders. The pigment of Mango violet also causes the decrease of microbiological activity when ester oil binder was used. Regardless of the type of oil binder, samples containing nylon SP 10, 0.15% of methyl paraben and 0.05% of propyl paraben had not been able to maintain microbiological activity only if the concentration of parabens were increased. Trace amounts of metal ions present in pigments reduced the activity of preservatives by inactivation of hydroxyl group of paraben. It is thought that swollen nylon SP 10 in ester oil increase the absorption or interaction of parabens and swollen nylon powder causes the inactivation of paraben.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.80-85
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• 2008

This study was carried out to assess the antidermatophytic potential of the ethyl acetate(EtOAc) extract of the marine isolate of Aspergillus sp.. The fungus was isolated by serial dilution, and was identified Aspergillus sp.. The EtOAc extract of the fungus was examined to evaluate the antidermatophytic efficacy against the fungal pathogens infecting human skin using the disc diffusion and MIC(minimum inhibitory concentration) determination methods. The EtOAc extract($5{\mu}l\;disc^{-1}$) was considered to have the antidermatophytic activity based on the inhibition percentage of the mycelial growth of the fungi tested such as Trichophyton mentagrophytes KCTC 6085, Microsporum canis KCTC 6591, Microsporum canis KCTC 6348, Trichophyton rubrum KCTC 6352, Microsporum canis KCTC 6349 and Trichophyton mentagrophytes KCTC 6316. The percentage of the inhibition ranged from 54% to 81, and the MIC obtained was 62.5, 62.5, 250, 125, 125, and $125{\mu}g\;ml^{-1}$, respectively. The extract had a strong detrimental effect on the spore germination of the tested skin infectious pathogens. These findings strongly support the role of the ethyl acetate extract as a potential antidermatophytic agent.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.20-20
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• 2015

Endophytic fungi are microorganisms inhabiting living plant tissues without causing apparent harm to the host. They are drawing increasing attention due to their ability to produce various bioactive compounds as well as their effects on host growth and resistance to biotic and abiotic stresses. As a first step to assess biodiversity of plant associated fungi in Korea and the following evaluation on diverse biological activities, we are collecting endophytic fungi from plant in wild followed by systematic long-term storage in liquid nitrogen. Molecular identification using ITS sequences was also incorporated for pure culture by hyphal tip isolation. As of April 2015, about 1,400 fungal strains had been isolated from about 170 plant taxa. Fungal isolates belonging to Pleosporales, Diaporthales, Glomerellales, Hypocreales, and Xylariales were the most abundant. These collections are being used for several complementary researches, including screening of isolates with novel bioactive compounds or conferring drought stress resistance, phylogenetic and genomic study. Genome sequencing was performed for 3 isolates, one Xylaria sp. strain JS573 producing griseofulvin, an antifungal compound, and two Fusarium spp. strains JS626 and JS1030, which are assumed to be new species found in Korea. More detailed analysis on these genomes will be presented. These collections and genome informations will serve as invaluable resources for identifying novel bioactive materials in addition to expand our knowledge on fungal biodiversity.