• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.22-22
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• 1992

국내의 토양에서 Streptomyces spp.를 분리하였고 이 중 항균활성이 우수한 균주들을 선별하였다. 이들 균주들을 적절한 조건에서 배양하여 얻은 배양액을 이온 교한 수지와 흡착 크로마토그래피를 행하여 항생물질들을 분리하였다. 이들 항생물질들은 Bacillus subtilis, Pyricularia oryzae, Alternaria mail, Candida albicans, Mycobacterium smegmatis, Pseudomonas aeruginosa , 및 Escherichia coli에 강한 항균활성을 나타내었다. 각 항생물질들을 산으로 가수분해하고 흡착관 크로마토그래피로 가수분해 생성물을 분리하였다. 분리한 항생물질과 가수분해 생성물들의 $^1$IH-NMR, $13^{C}$ -NMR, FAB-Mass 스펙트럼을 분석하여 구조를 연구하였다.

• The Plant Pathology Journal
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• v.34 no.5
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• pp.356-366
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• 2018

The red flour beetle, Tribolium castaneum, is one of the most common and economically important pests of stored cereal products worldwide. Furthermore, these beetles can act as vectors for several fungal post-harvest diseases. In this study, we collected T. castaneum from 49 rice processing complexes (RPCs) nationwide during 2016-2017 and identified contaminating fungal species on the surface of the beetles. Five beetles from each region were placed on potato dextrose agar media or Fusarium selection media after wet processing with 100% relative humidity at $27^{\circ}C$ for one week. A total of 142 fungal isolates were thus collected. By sequence analysis of the internal transcribed spacer region, 23 fungal genera including one unidentified taxon were found to be associated with T. castaneum. The genus Aspergillus spp. (28.9%) was the most frequently present, followed by Cladosporium spp. (12.0%), Hyphopichia burtonii (9.2%), Penicillium spp. (8.5%), Mucor spp. (6.3%), Rhizopus spp. (5.6%), Cephaliophora spp. (3.5%), Alternaria alternata (2.8%) and Monascus sp. (2.8%). Less commonly identified were genera Fusarium, Nigrospora, Beauveria, Chaetomium, Coprinellus, Irpex, Lichtheimia, Trichoderma, Byssochlamys, Cochliobolus, Cunninghamella, Mortierella, Polyporales, Rhizomucor and Talaromyces. Among the isolates, two known mycotoxin-producing fungi, Aspergillus flavus and Fusarium spp. were also identified. This result is consistent with previous studies that surveyed fungal and mycotoxin contamination in rice from RPCs. Our study indicates that the storage pest, T. castaneum, would play an important role in spreading fungal contaminants and consequently increasing mycotoxin contamination in stored rice.

• 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.

• Research in Plant Disease
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• v.18 no.4
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• pp.261-267
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• 2012

Inspection of deteriorated rices in Korea for fungal occurrence revealed that Aspergillus was the most frequently observed genus and some isolates of the Aspergillus spp. turned out to produce aflatoxin. Diverse fungal genera including Fusarium, Aspergillus, Penicillium, or Alternaria spp. were observed in most of the rice samples. Aflatoxin occurred infrequently and the levels of aflatoxin present in the rice samples were lower than regulatory limit but Fusarium toxins such as deoxynivalenol, nivalenol, zearalenone, and fumonisin occurred frequently. In rice processing complexes, fungal and mycotoxin contamination of rice decreased by milling process, resulting in the lowest level of mycotoxin and fungi in polished rice. Currently, it appears that Korean rice and milled by-products need a safety control for Fusarium toxins rather than aflatoxin.

• Korean Journal of Agricultural Science
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• v.20 no.1
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• pp.18-24
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• 1993

This experiment was focused on determining the potential of sodium hypochlorite (NaOCl) as fungicide against seed-borne fungi. Effects of NaOCl to control seed-borne fungi were compared to the those of Benlate T in several crop seeds. 1. The effect of NaOCl on disinfection of sesame seeds without imparing germination was highest in the range of 1-2% solution for 10 min. Also, a 30 min immersion of rice seed in 1-2% solution reduced incedence of seed-borne fungi. 2. Alternaria spp. in seeds of radish and chinese cabbage and Colletoricum spp. in pepper were significantly reduced by a 10 min immersion of seeds in 1% NaOCl. 3. The effective control range of NaOCl for seed-borne fungi was much wider than that of Benlate T in sesame seeds. No clear difference between chemicals was found in rice seeds. However, germination of seeds were impaired at 1-2% NaOCl immersion for more than 1 hour.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.93-99
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• 2013

The disease and insect were surveyed locally in greenhouse, fruit packing house and store house of 51 farms in 13 towns having purpose of paprika exportation. By analysis, various disease and insect were not only founded locally but more ones detected in farms having old facilities and no natural enemy. We found 15 pathogens such as Fusarium spp., Alternaria solani, Leveilluila taurica, PepMV (Pepino mosaic virus) and TMV (Tobacco mosaic virus) in greenhouse, Fusarium spp. in fruit packing house and Penicillium spp. in store house. We found 15 insects in greenhouse such as Bemisia tabaci, rialeurodes vaporariorum and Myzus persicae in greenhouse, Hylobitelus haroldi in fruit packing house. However, the problem quarantine disease and insect for importation and exportation were not detected in inspection time.

• The Plant Pathology Journal
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• v.32 no.6
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• pp.519-527
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• 2016

Purple blotch, caused by Alternaria porri (Ellis) Cifferi, is a serious disease incurring heavy yield losses in the bulb and seed crop of onion and garlic worldwide. There is an immediate need for identification of effective resistance sources for use in host resistance breeding. A total of 43 Allium genotypes were screened for purple blotch resistance under field conditions. Allium cepa accession 'CBT-Ac77' and cultivar 'Arka Kalyan' were observed to be highly resistant. In vitro inoculation of a selected set of genotypes with A. porri, revealed that 7 days after inoculation was suitable to observe the disease severity. In vitro screening of 43 genotypes for resistance to A. porri revealed two resistant lines. An additional 14 genotypes showed consistent moderate resistance in the field as well as in vitro evaluations. Among the related Allium species, A. schoenoprasum and A. roylei showed the least disease index and can be used for interspecific hybridization with cultivated onion. Differential reaction analysis of three A. porri isolates (Apo-Chiplima, Apn-Nasik, Apg-Guntur) in 43 genotypes revealed significant variation among the evaluated Allium species (P = 0.001). All together, the present study suggest that, the newly identified resistance sources can be used as potential donors for ongoing purple blotch resistance breeding program in India.

• Research in Plant Disease
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• v.17 no.2
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• pp.148-154
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• 2011

This study was conducted to control the seed borne pathogens (Alternaria spp.) of carrot and to examine the seed germination rate by using 13 environment friendly agricultural materials instead of conventional chemicals for organic cultivation. The growth inhibiting effects on pathogens showed the different responses according to each agricultural material and effective 7 materials against seed borne pathogens were selected. Among 7 materials, the carrot seeds sterilized with plant extracts, Tanger Stop and Land Saver were not germinated at all. The germination rate of seeds sterilized with other materials showed the similar levels with reference chemical (Benlate-T) and non-treated seeds. Infection rates of seeds sterilized with seaweed extract, Bellopper for controlling A. radicina and plant extract, Ssial-100 for A. dauci were similar or low infection rate compared with reference chemical. The germination rate and root length of seeds sterilized with Bellopper and Ssial-100 was similar or superior to those of chemical sterilized seeds. The optimal condition seemed to be a little bit different depending on the concentration of materials. As a result, the sterilization of carrot seeds by using the environment friendly materials could be effectively utilized as a technology to inhibit the infection of seed-borne pathogens.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.158-164
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• 1995

토마토의 엽권에서 분리한 Fusariym graminearum이 분비하는 물질은 벼 도열병균(Pyricularia oryzae)의 여러 종의 식물병원 진균에 대한 항균활성을 나타내었으며, 이러한 활성물질을 PDA에서 본 균을 배양 한 후 chloroform으로 추출하여 분리정제 하였다. HPLC에 의하여 5종류의 활성 물질을 분획하였으며, 그중 1번(F402) 화합물을 벼 도열병균(P. oryzae)을 포함한 22개 식물 병원 진균에 대하여 살균 활성범위를 조사한 결과, 이 화합물은 50$\mu\textrm{g}$/ml 농도에서 Pythium ultimum, Rhizoctonia solani, Sclerotinia sclerotiorum은 전혀 억제하지 못하였으며, Phytophthora spp., Cladosporium fulvum, Fusarium spp., Corynespora cassicola에는 어느 정도의 활성이 있었지만 낮게 나타났고, P. oryzae, Cochliobolus miyabeanus, Alternaria solani는 100% 억제하여 활성이 높게 나타났다. 또한 장내 세균에 대한 활성을 MIC로 비교할 때 Streptococcus pyogenes, Streptococcus faecium에 대하여는 각각 12.5, 25 $\mu\textrm{g}$/ml였고 Staphylococcus aureus는 25-50$\mu\textrm{g}$/ml으로 나타났으며, Pseudomonas aeruginosa, Salmonella typhimurium, Klebsiella aerogenes, Enterobacter cloacae에서는 100$\mu\textrm{g}$/ml 이상으로 활성이 나타나지 않았다. F402를 200$\mu\textrm{g}$/ml의 농도로 직접 살포한 식물체에서의 방제효과는 벼도열병, 벼 깨씨무늬병, 보리 흰 가루병에 대하여는 80%이상이었으나, 벼 잎집무늬마름병, 오이 잿빛곰팡이병, 토마토 역병, 밀 녹병에서는 낮았다.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.229-235
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• 2014

Pear skin stains on 'Niitaka' pears, which occur from the growing stage to the cold storage stage, reportedly negatively influence the marketing of pears. These stains on fruit skin are likely due to a pathogenic fungus that resides on the skin and is characterized by dark stains; however, the mycelium of this fungus does not penetrate into the sarcocarp and is only present on the cuticle layer of fruit skin. A pathogenic fungus was isolated from the skin lesions of infected fruits, and its pathogenicity was subsequently tested. According to the pathogenicity test, Mycosphaerella sp. was strongly pathogenic, while Penicillium spp. and Alternaria spp. showed modest pathogenicity. In this present study, we isolated the pathogenic fungus responsible for the symptoms of pears (i.e., dark brown-colored specks) and identified it as Mycosphaerella graminicola based on its morphological characteristics and the nucleotide sequence of the beta-tubulin gene. M. graminicola was pathogenic to the skin of 'Niitaka' pears, which are one of the most widely growing varieties of pears in South Korea.