• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.599-606
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• 2004

Gram-positive antagonistic bacilli were isolated from agricultural soils for possible use in biocontrol of plant pathogenic fungi, Fusarium oxysporum, Rhizoctonia solani, and/or Pythium ultimum. Among the 65 antagonistic Gram-positive soil isolates, 22 strains were identified as Bacillus species by 16S rDNA sequence analyses. Four strains, including DF14, especially exhibited multiple antagonistic properties against the three damping-off fungi. Genotypic properties of the Bacillus isolates were characterized by rapid molecular fingerprinting methods using repetitive extragenic palindromic-PCR (REP-PCR), ribosomal intergenic spacer-length polymorphisms (RIS-LP), 16S rDNA PCR-restriction fragment length polymorphisms (PCR-RFLP), and strain-specific PCR assays. The results indicated that the REP-PCR method was more valuable than the RIS-LP and 16S rDNA PCR-RFLP analyses as a rapid and reliable approach for bacilli typing and identification. The use of strain-specific primers designed based on 16S rDNA sequence comparisons enabled it to be possible to selectively detect a strain, DF14, which is being used as a biocontrol agent against damping-off fungi.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.55-55
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• 2002

Occurrences of diseased sweet flag (Acorus calamus L. var. asiaticus) were found in Chonju and Buan Province, on August 2002. The typical symptoms of the disease affected the leaves, pods, and collar of the infected plants. The leaves or pods became darker brown, then dry rotted, and white fluffy mycelia formed on the lesion. The collar, of the infected plants, formed black spot. The spores grew rapidly on PDA medium. Pathogenic fungi have not been identified clearly, as of yet. These fungi were formed from developed spores, as well as, undeveloped spores. These fungi suggest that Fusarium sp. and Rhizoctonia sp.. The range of temperatures were tested from 5$^{\circ}C$ to 35$^{\circ}C$ for mycelial growth. The optimum temperature for growth was 3$0^{\circ}C$. This is the first report on the fungus disease of sweet flag by some pathogens, in Korea. We would like to do further research for single spore isolation, pathogenity, and characterization of fungi.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.10-19
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• 2012

This study investigated the distribution of endophytic fungi obtained from the surface sterilized tissues of leaves, stems and roots of chili pepper ($Capsicum$ $annuum$ L.) plants in seedling, flowering and fruiting stages in Korea and their antifungal activity. A total of 481 isolates were recovered and were identified using molecular techniques. Based on rDNA ITS gene sequence and phylogenetic analysis, 21 fungal genera were characterized, belonging to 16 Ascomycota and 5 Basidiomycota. $Penicillium$ in seedling stage, $Fusarium$ in flowering stage, $Colletotrichum$ followed by $Fusarium$, $Alternaria$ and $Xylaria$ in fruiting stage was predominant and $Alternaria$, $Cladosporium$ and $Fusarium$ were common in all growth stages. Among 481 endophytes 90 phenotypes were evaluated for the antimicrobial activity against three major pathogens ($Phytophthora$ $capsici$, $Colletotrichum$ $acutatum$ and $Fusarium$ $oxysporum$) of chili pepper. Among them 16 isolates inhibited the growth of at least one test microorganisms. Three strains showed a broad spectrum antifungal activity and displayed strong inhibition against chili pepper pathogenic fungi.

• Mycobiology
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• v.33 no.4
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• pp.206-209
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• 2005

Narceine methyl ester and narceine are potent alkaloids which were isolated from Corydalis longipes were found effective in vitro at very low concentration, i.e., $100{\sim}500\;ppm$ against spore germination of some test plant pathogenic fungi (Alternaria solani, A. tagetica, Cercospora abelmoschi, Curvularia maculans, Erysiphe cichoracearum, E. pisi, Fusarium udum, Helminthosporium oryzae, H. penniseti, Ustilago cynodontis). Among the test, phytopathogens the spores of F. udum, C. maculans and H. penniseti were highly sensitive at 200 ppm. However, spores of E. pisi, A. solani and A. tagetica were less sensitive at low concentration followed by other test fungi. Most of the fungi showed zero or nearly zero percent spore germination at 400 and 500 ppm.

• Mycobiology
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• v.30 no.1
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• pp.55-56
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• 2002

The 4',7-dimethoxyisoflavone was isolated from the leaves of Albizzia lebbeck for the first time. This flavonoid showed antifungal activity against some plant pathogenic fungi tested in vitro, e.g., Alternaria melongenae, A. brassicicola, A. brassicae, Curvularia maculans, C. pallescens, C. lunata, Curvularia species, Colletotrichum species, Helminthosporium penniseti and H. speciferum. The sensitivity of different fungi to this chemical varied considerably. A. brassicae was most sensitive as complete inhibition of germination was observed in all the concentrations(100 to 1000 ppm) of the chemical. Similar effect on H. speciferum and Curvularia species was also recorded at 500 ppm, whereas H. penniseti did not germinate at 250 ppm. A. melongenae and A. brassicicola also did not germinate at 1000 ppm while 750 ppm was inhibitory to C. lunata and C. maculans. Germination in almost all fungi was significantly inhibited at each concentration in comparison to control except Curvularia sp. and H. speciferum. Use of 4',7-dimethoxyisoflavone to control some plant diseases under field conditions has been suggested.

• The Plant Pathology Journal
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• v.38 no.1
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• pp.33-45
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• 2022

To screen antagonistic fungi against plant pathogens, dual culture assay (DCA) and culture filtrate assay (CFA) were performed with unknown soil-born fungi. Among the different fungi isolated and screened from the soil, fungal isolate ANU-301 successfully inhibited growth of different plant pathogenic fungi, Colletotrichum acutatum, Alternaria alternata, and Fusarium oxysporum, in DCA and CFA. Morphological characteristics and rDNA internal transcribed spacer sequence analysis identified ANU-301 as Aspergillus terreus. Inoculation of tomato plants with Fusarium oxysporum f. sp. lycopersici (FOL) induced severe wilting symptom; however, co-inoculation with ANU-301 significantly enhanced resistance of tomato plants against FOL. In addition, culture filtrate (CF) of ANU-301 not only showed bacterial growth inhibition activity against Dickeya chrysanthemi (Dc), but also demonstrated protective effect in potato tuber against soft rot disease. Gas chromatography-tandem mass spectrometry analysis of CF of ANU-301 identified 2,4-bis(1-methyl-1-phenylethyl)-phenol (MPP) as the most abundant compound. MPP inhibited growth of Dc, but not of FOL, in a dose-dependent manner, and protected potato tuber from the soft rot disease induced by Dc. In conclusion, Aspergillus terreus ANU-301 could be used and further tested as a potential biological control agent.

• Journal of Veterinary Clinics
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• v.7 no.2
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• pp.489-495
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• 1990

The purpose of this study was to investigate the contamination rates of Keratinophilic fungi in soils In Chonju. From september to November 1986, 98 soil samples were collected at the school and children's play ground, dog barn, pig barn, cow barn, horse barn and fowl barn( total 33 sites ). The samples were collected at the different depths(0～2cm, 30cm, 50cm ) in each of the sites, respectively. Each sample was cultured at 25$^{\circ}C$ according to Modified hair baiting method by using horse mane hair as a bait. The results obtained were summerized as follows ; 1. Eighty one of the 98 soil samples were found to be positive for Keratinophilic fungi. 2. In the examination of keratinophilic fungi in 98 soil samples, the organisms isolated weie as follows; Microsporum gypseum 20, Trichophyton ajelloi 15, Chrysosporium tropicum 40, C. Keratinophilum 24, C. tuberculatum 6 and Chrysosporium spp. like organism 4 strains. 3. The positive rates of keratinophilic fungi in each of the depths were 87.9%(29/33) in surface layer, 90.9%(30/33) in middle layer and 68.8％(22/32) in deep layer. 4. The positive rates of Keratinophilic fungi in each of the sites were 100%(3/3) in horse barn 91.7％ (l1/12) in dog barn, 88.9%(16/18) in pig barn, 86.7%(13/15) in cow barn, 76.2%(16/21) in fowl barn and 75.9%(22/29) in school and children's play ground. 5. The isolation rates of M. gypseum, Pathogenic fungi for human and animals, were as follows ; 58.3％ in dog barn(surface layers 100％, middle layers 50％, deep layers 25％) and 16.7％ in pig barn(surface 33.3％, middle 16.7%, deep 0％). In the cow barn, the isolation rates were 13.3%(surface 40.0％, middle 0%, deep 0％) and 10% in horse barn(surface l00％, middle 100%, depp 100%). In the fowl barn, the isolation rates was 19.1%(surface 28.8%, middle 14.3%, deep 14.3%) and 3.5% in school and children's play ground(surface 0％, middle 0％, deep 11.1%).

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.415-418
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• 1999

Thecodiplosis japonensis is an important insect pest in pine trees and hard to be controlled by chemical pesticides due to its characteristic life cycle. Experiments were conducted to determine the pathogenicity and growth temperature of several entomopathogenic fungi as potential microbial insectcides for T. japonensis. Beauveria bassiana SFB-SC and Paecilomyces fumosoroseus SFP-198 were highly pathogenic against T. japonensis. B. bassiana SFB-SC had also pathogenicity against a beneficial insect Bombyx mori. Growth rate and pathogenicity of P. funmosoroseus SFP-198 under 15$^{\circ}C$ was higher than those of B. bassians SFB-SC. These results indicated that P. fumosoroseus SFP-198 is a potential microbial control candidate for control of T. japonensis.

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1031-1036
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• 2005

[ $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ ] (1) was isolated from an ethyl acetate extract of the root bark from Lycium chinense Miller, and its structure was determined using 1D and 2D NMR spectroscopy including DEPT, HMQC, and HMBC. $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ exhibited potent antimicrobial activity against antibiotic-resistant bacterial strains, methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients, and human pathogenic fungi without having any hemolytic effect on human erythrocytes. In particular, compound 1 induced the accumulation of intracellular trehalose on C. albicans as stress response to the drug, and disrupted the dimorphic transition that forms pseudo-hyphae caused by the pathogenesis. This indicates that $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ has excellent potential as a lead compound for the development of antibiotic agents.

• Mycobiology
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• v.30 no.2
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• pp.96-101
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• 2002

Four pathogenic fungal isolates belonging to different genera including Alternaria, Fusarium and Curvularia were isolated from selected diseased weeds growing in the fields in Dakahalia district. The inoculum of these pathogenic fungi specific to weeds were cultured, standardized and formulated as alginate pellets containing mycelium plus culture filtrate. These mycoherbicides were evaluated for disease severity(DS). Maximum DS was obtained with the alginate pellets of mycelium filtrate Fusarium solani. Physiological changes of the treated weed were determined 5 aiid 10 days after treatments. As compared to the healthy weeds, all mycoherbicide formulations significantly decreased the amount of photosynthetic pigments and subsequently soluble and insoluble sugars in the infected weeds. The mycoherbicide formulation of F. solani had the greatest effect on lowering to the abovementioned amount in the leaves of Chenopodium murale. Generally, treatment of weed leaves with the specific mycoherbicide led to a highly significant increase in total phenol content when compared to the healthy control weed. C. murale infected with the mycoherbicide formulation of F. solani had higher levels of phenolic compounds than those other treated weeds particularly after 10 days of inoculation.