• Mycobiology
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• v.31 no.3
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• pp.157-161
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• 2003

Various soil samples were collected from twenty-four areas of ten different poultry farms in Korea and screened for prevalence of keratinolytic fungi. Fourteen species of feather-associated fungi belonging to ten genera Acremonium, Alternaria, Aspergillus, Cladosporium, Curvularia, Fusarium, Monascus, Mucor, Penicillum, and Verticillium isolated from poultry soils were grown on keratin medium. Especially, Aspergillus spp. populations associated with the soil sample is $1{\times}10^5$ cfu/g. A. flavus, A. fumigatus, A. niger, A. nidulans, and A. terreus could utilize keratin of chicken feather and degrade it, producing sulphydryl-containing compounds detected as keratinase, cysteine and total proteins. Keratinolytic activities of five Aspergillus species also changed the pH of the medium more alkaline than those that were less keratinolytic.

• Mycobiology
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• v.35 no.2
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• pp.69-71
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• 2007

1-Corydalmine, an alkaloid isolated from roots of Corydalis ehaerophylla inhibited spore germination of some plant pathogenic as well as saprophytic fungi e.g. Alternaria brassicae, A. brassicieola, A. solani, Curvularia lunata, C. maculans, C. sp., C. pallseens, Erysiphe pisi, Fusarium udum, Helminthosporium species, H. penniseti and a Heterosporium species. 1-Corydalmine significantly inhibited spore germination of all the fungi at 100 to 1500 ppm. It was effective against all the fungi at 1500 ppm. C. lunata was highly sensitive to this chemical even at 250 ppm.

• Preventive Nutrition and Food Science
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• v.3 no.1
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• pp.43-47
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• 1998

The incidence of total molds, Fusarium species, and the estrogenic mycotoxin,zearalenone, in Korean grain samples were investigated . The majority of molds infecting grain were identified as belonging to the genus Alternaria , with an average infection rate of kernels of 43% and 32% in rice and baley, respectively. Fusarium speciens were less common, with average infection rates of 13% and 19% in reice and barley, respectively. A number of field fungi including Curvularia and Dactylaria were also observed. Among the Fusarium speices, 71 of 94 Fusarium isolates were identified as F.semitectum. A few F. moniliforme and F. equiseti were observed linked immunosorbent assay (ELISA) or high-performance liquid chromatography(HPLC). In addition, deoxynivalenol was not deteted by ELISA . However, thepresence of molds, including Fusarium species, may pose possbile health hazards to persons consuming those grains.

• Journal of Life Science
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• v.8 no.5
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• pp.537-549
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• 1998

This investigation was performed to isloate and identify the total bacteria, Staphylococcus spp. and fungi from the indoor air exposed for 30 minutes on the blood agar plate at the 27 places in a hospital. Antibiotic susceptibility tests of the isolated bacteria were also studied. The mean numbers of total bacteria, Staphylococci spp. and fungi were 26, 17, and 2 in the summer and 19, 8, and 2 in the winter, respectively. Staphylococcus epidermidis was the most common isolated bacteria, and the next was Staphylococcus aureus, Aerococcus spp., Micrococcus spp., and Bacillus spp. from the indoor-air of hospital. Aspergillus spp., Cephalosporum spp., Curvularia spp., penicillium spp., and Phialophora spp. was frequently isolated from the indoor-air of hospital. The 109 strains of isolated Staphylococcus epidermidis sho-wed resistance to tetracycline(45.0%), methicillin(40.2%), erythromycin(31.2%), and kanamycin(24.8%). The 76 strains of isolated Staphylococcus aureus showed resistance to erythromycin(71.7%), methicillin(63.2%), kanamycin (44.7%), tetracycline(39.5%), and ampicillin(32.9). The 67 strains of isolated Aerococcus spp. showed resistance to erythromycin(26.9%), methicillin(25.4%), kanamycin(22%), and tetracycline(22.4%). The 48 strains of isolated Micrococus spp. showed resistance to tetracycline(27.0%), methicillin(22.9%), erythromycin(22.9%), and kanamycin(20.8%).

• Research in Plant Disease
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• v.11 no.2
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• pp.93-97
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• 2005

In order to detect casual agents associated with ear blight of rice, seed samples of 'Ilmi-byeo' and 'Daesan-byeo', susceptible cultivars were collected from 28 regions on a nationwide scale. Finally 23 fungi including Bipolaris oryzae($10.3\%$), Alternaria alternata ($10.2\%$), Cladosporium sp. ($7.5\%$), Nigrospora oryzae($5.2\%$) and Phoma sorghina ($6.3\%$) from seeds of 'Ilmi-byeo', and 13 fungi including N. oryzae ($15.1\%$), A. alternata ($9.6\%$) and Curvularia lunata ($2.2\%$) from seeds of 'Daesan-byeo' were detected. In case of discolored seeds caused by rice ear blight, B. oryzae($15.5\%$), A. alternata ($5.5\%$), Fusarium graminearum ($8.0\%$), N. oryzae($5.2\%$) and P. sorghina ($4.5\%$) were detected even from the hulled rice of Ilmi-byeo.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.259-269
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• 2019

Brown spot and sheath rot of rice are caused by fungal pathogens such as Curvularia lunata, Cochliobolus miyabeanus, and Sarocladium oryzae, and cause losses such as reduced rice yield and quality, which is an enormous problem with serious long-term effects. To search biological control agents of phytopathogenic fungi, five kinds of useful Bacillus-like isolates which are excellent in extracellular enzyme activity and produce siderophore were selected from paddy soil of Sunchang in Korea. The selected isolates were tested for excellent antifungal activity against three of the phytopathogenic fungi that frequently occur in rice, and JSRB 177 strain had the most excellent antifungal activity. Based on the experimental results, JSRB 177 is finally selected as a candidate for biological control and identified to Bacillus subtilis through 16S rRNA sequence analysis. In addition, physiological characteristics of JSRB 177 confirmed by analysis of carbohydrate fermentation patterns and enzyme production ability. Based on the above results, JSRB 177 is expected to be used as a biological control agent for the rice pathogenic fungi. In the future, further studies related to industrialization such as port test and establishment of mass production process are needed.

• Mycobiology
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• v.33 no.3
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• pp.147-149
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• 2005

The investigation was undertaken to enhance the decomposition process by pre-treatment of rice stubble, having higher concentration of lignin. Air-dried rice stubble was treated with 1.8 liter of 1% NaOH and autoclaved. Six cellulolytic fungi, Trichoderma harzianum, Penicillium citrinum, Curvularia lunata, Aspergillus flavus and Alternaria alternata were grown in basal synthetic medium along with delignified rice-residue as carbon source for production of soluble crude protein. Though the loss of cellulose has been observed by all of them but having a considerable status in the presence of T. harzianum and T. harzianum yielded highest percentage of crude protein (27.99%) with biomass of 375 mg, whereas the lowest protein value (17.91%) was recorded in case of A. niger with biomass of 422 mg. Among the imperfect fungi, T. harzianum was the most potent. Effects of incubation period and nitrogen sources on soluble crude protein production by T. harzianum were also undertaken in this study. Fifth day of incubation period and potassium nitrate as nitrogen source among other nitrogen sources was found most appropriate for soluble crude protein production by the mentioned organism.

• 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.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.378-381
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• 2014

A new pathogen was isolated from zoysiagrass-planted park of Jeju island in 2014. Symptoms appeared a type of irregular patches occurring brownish leaf blight, followed by stem and crown rot. The symptom was very similar to that of large patch caused by Rhizoctonia solani, a well-known devastating zoysiagrass disease. The isolate showed thin orange-colored mycelia and screlotia were formed on the medium based on cultural characteristics. The causal agent of the disease was finally identified as Waitea circinata by analysis of ribosomal DNA. On the inoculation test, Waitea circinatae showed strong pathogenicity to the zoysiagrass. The mycelia were obviously observed in the inoculated tissues. This is the first report of Waitea ring patch caused by Waitea circinata on zoysiagrass.

• Journal of Microbiology and Biotechnology
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• v.28 no.9
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• pp.1527-1535
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• 2018

Bacterial strain BAS23 was isolated from rice field soil and identified as Bacillus amyloliquefaciens. Based on dual culture method results, the bacterium BAS23 exhibited potent in vitro inhibitory activity on mycelial growth against a broad range of dirty panicle fungal pathogens of rice (Curvularia lunata, Fusarium semitectum and Helminthosporium oryzae). Cell-free culture of BAS23 displayed a significant effect on germ tube elongation and mycelial growth. The highest dry weight reduction (%) values of C. lunata, H. oryzae and F. semitectum were 92.7%, 75.7%, and 68.9%, respectively. Analysis of electrospray ionization-mass spectrometry (ESI-MS) and $^1H$ nuclear magnetic resonance (NMR) spectroscopy revealed that the lipopeptides were iturin A with a C14 side chain (C14 iturinic acid), and a C15 side chain (C15 iturinic acid), which were produced by BAS23 when it was cultured in nutrient broth (NB) for 72 h at $30^{\circ}C$. BAS23, the efficient antagonistic bacterium, also possessed in vitro multiple traits for plant growth promotion and improved rice seedling growth. The results indicated that BAS23 represents a useful option either for biocontrol or as a plant growth-promoting agent.