• 한국균학회지
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• 제17권1호
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• pp.39-47
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• 1989

54과(科) 100종(種)의 식물 추출액(抽出液)을 공시(供試)하여 Phytophthora spp.에 대한 항균성(抗菌性)을 검정(檢定)한 바 균사생장(菌絲生長) 억제효과(抑制效果)가 있는 것은 양파, 마늘, 등배나무, 호장근 및 당대황이었고 이중에서 특히 마늘과 등배나무가 가장 뚜렷하게 나타냈다. 유주자낭(遊走子囊) 발아억제효과(發芽抑制效果)는 P. capsici에서 마늘, 등배나무 및 당대황이 뚜렷했고 P. nicotiana 와 P. infestans에서는 등배나무가 뚜렷했다. 또한 등배나무 추출액(抽出液)이 유묘(幼苗)에서 강(强)한 발병억제효과(發病抑制效果)를 나타냈다. 이상의 결과로 보아 항균물질(抗菌物質)은 분비(分泌)하는 능력을 가진 길항식물(拮抗植物)을 이용하여 토양전래성(土壤傳來性) 병원균(病原菌)을 저지(沮止)할 가능성이 있다고 믿는다.

• 한국유기농업학회지
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• 제8권3호
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• pp.121-130
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• 2000

사과 저장중에 발생하는 푸른곰팡이병원균에 대한 길항미생물을 찾기 위하여 자연계로부터 유용미생물을 분리하여 Penicillum expansum에 대한 길항력 검정과 동정하였다. 자연계로부터 얻은 3,000여종의 미생물중에서 푸른곰팡이병원균에 대하여 길항력이 우수한 미생물을 1차적으로 11종 선발하였으며, 이중에서 가장 길항력이 뛰어난 미생물을 치종적으로 KB22를 선발하였다. 길항력이 우수한 KB22의 형태적 성질, 배양적 특성 및 생리 생화학적 성질 등을 조사하여 비교 검토한 결과 Bacillus subtilis와 유사한 균으로 동정되었다. 분리한 길항균 Baillus subtilis KB22는 푸른곰팡이병에 대한 55.9%의 높은 생장억제력을 보였으며, 한천배지에서 Penicillum expansum 접종 후 길항균처리와 열처리한 길항균배양액을 처리하였을 때 각각90%와 15%이상 길항력을 보여주었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2010년도 정기총회 및 춘계학술발표회
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• pp.6-6
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• 2010

Bacteria of the Bacillus sp. are well known to possess antagonistic activity against numerous plant pathogens. In the present study, 11 Bacillus sp. were isolated from the brackish environment and assayed for antagonistic activity under in vitro and in vivo conditions. Among the 11 isolates tested, 9 isolates effectively inhibited the growth of various plant pathogens, namely Phytophthora capsici, Phytophthora citropthora, Phytophthora citricola, Phytophthora sojae, Colletotricum coccodes, Colletotricum gloeosporioides, Colletotricum acutatum, Rhizoctonia solani, Fusarium solani, Fusarium graminearum, Pyricularia sp. and Monilina sp. The effective isolates were further screened for Phytophthora blight suppression in Capsicum annuum L. under green house conditions. The isolate SB10 exhibited the maximum (72.2%) reduction in disease severity. The antifungal compounds from the isolate were isolated and characterized. The isolated compounds exhibited high thermo stability ($100^{\circ}C$ for 30 min). Matrix-Assisted Laser Desorption Ionization-Time of Flight investigation of the antifungal compounds revealed three lipopeptide complexes, the surfactins, the iturins, and the fengycins.

• 한국식물병리학회지
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• 제14권3호
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• pp.268-277
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• 1998

The production of Korean ginseng, one of the most important medicinal root crops, is limited by many factors including soil sickness, root rots in fields as well as during storage prior to consumption. Although much research has been conducted on the diseases in field condition, little information is available on the control of postharvest roots rots. To obtain better management strategy of postharvest root rots in ginseng, biological control using antagonistic bacteria was attempted. Of 208 bacteria obtained form suppressive soil samples, 4 were selected based on the inhibitory effect on mycelial growth of two major causal fungi for postharvest root rots in ginseng, Botrytis cinerea and Fusarium solani. The culture filtrates of these bacterial antagonists greatly inhibited the conidial germination of both pathogenic fungi and produced abnormal morphology such as swollen germ tubes in F. solani and vacuolation of nongerminated conidia in B. cinerea. The population levels of bacterial antagonists on the ginseng roots were gradually increased up to 8 days of incubation. Postharvest root rots of ginseng caused by f. solani and B. cinerea were controlled in dipping tests in the ranges of 60∼80% by antagonistic Bacillus spp. obtained from suppressive soil. These results suggest that biological control using these antagonistic bacteria would be an alternative strategy to control postharvest root rots in ginseng.

• 한국식품위생안전성학회지
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• 제4권2호
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• pp.155-163
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• 1989

YS-medium(0.1% Yeast extract +10% Skimmilk)중에 유산간균 L.casei, L. acidophilus , L. bulgaricus 와 병원성 E, coli, Sal. enteritides를 혐기적으로 혼합배양하면서 각각의 생육과 저해를 조사한 결과 , E. coli와 Sal. enteritideis의 생육이 각 유산균에 의하여 현저하게 저해되었다. 그러나 L.casei와 L.acidophilus의 각 유산균은 E.coli와 Sal. enteritidis에 의하여 생육이 전혀 저해되지 않았고 , L. bulgaricus는 E. coli 에 의하여 약간 저해를 받았다. E. coli와 Sal. enteritidis 의 단독배양액의 pH는 72시간째에 각각 5.08과 5.70이었으며, 유산균혼합배양액의 pH는 3.75~4.48이었고, 병원성균의 생육억제작용은 주고 pH 저하에 기인하였다.

• 한국유기농업학회지
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• 제23권1호
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• pp.133-148
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• 2015

Although several adverse effects have been increased in recent years, synthetic agro-chemicals have been widely used to control diseases on paprika. This research was conducted to isolate and to characterize the antagonistic microorganism to control major paprika diseases, gray mold rot, fruit and stem rot, phytophthora blight, sclerotium rot, and wilt disease. Analysis of the fatty acid and analysis of the 16S rDNA gene sequence revealed that YKJ2 isolated in this research belongs to a group of Burkholderia cepacia. Specially, 16S rDNA gene sequence of YKJ2 showed 99% of sequence similarity with B. cepacia. Observation through the optical microscope revealed that YKJ2 was effective on suppression of the spore germination and the hyphal growth of pathogens. YKJ2 treatment on pathogens induced marked morphological changes like hyphal swelling and degradation of cell wall. In the case of phytophthora blight, the zoosporangium formation was restrained. On the basis of the results of this study, we propose that an antagonistic microorganism, B. cepacia, found in this study naming as "B. cepacia strain YKJ2" and has great potential as one of biological control agents against major diseases of paprika.

• The Plant Pathology Journal
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• 제28권2호
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• pp.156-163
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• 2012

Stem rots caused by Rhizoctonia solani and Sclerotinia sclerotiorum have been known as devastating diseases in balloon flower plants. Antifungal activities of four fungicides, azoxystrobin, polyoxin B, trifloxystrobin and validamycin A were evaluated in vitro, showing effective suppression with mycelial growth of the fungal isolates on PDA media. Efficacies of the four fungicides were also demonstrated in stem tissues of balloon flower plants against R. solani and S. sclerotiorum. A commercially available Bacillus subtilis strain Y1336 was tested in terms of antagonistic biological control of stem rot disease of balloon flower plants. The bacterial strain revealed its antifungal activities against R. solani and S. sclerotiorum demonstrated by dual culture tests using paper discs and two plant pathogenic fungi on PDA media, as well as by plant inoculation assay, indicating that this antagonistic bacterial strain can be incorporated into disease management program for balloon flower stem rot diseases together with the four chemical fungicides.

• Journal of Applied Biological Chemistry
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• 제42권3호
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• pp.146-150
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• 1999

As a part of the integrated disease system in greenhouse, an antifungal fungus(AF1) was isolated from greenhouse soil. It exhibited strong inhibitory activites against Pythium ultimum, Phytophtora capsici, Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum based on dual culture on 1/5 strength of potato dextrose agar between antagonistic fungus and several plant pathogens. The antagonistic fungus was identified as Chaetomium cochliodes, based on morphological characteristics; the body of the perithecium bears straight or slightly wavy, unbranched hairs, whilst the apex bears a group of spirally coiled hairs. To investigate antagonistic principles, antifungal compound was extracted and fractionated by different solvent systems. An antifungal compound was isolated as pure crystal from is culture filtrate using organic solvent extraction and column chromatography, followed by preparative thin layer chromatography. The chemical structure of the purified antifungal compound was identified as chaetoglobosin A based on the data obtained form $^1H-NMR$, $^{13}C-NMR$, DEPT 90, 135, $^1H-^1H$ COSY, $^1H-^{13}C$ COSY and EI/MS. $ED_{50}$ values of the chaetoglobosin A against P. ultimum, P. capsici, R. solani, B. cinerea and F. oxysporum were 1.98, 4.01, 4.16, 2.67 and 35.14 ppm, respectively.

• Journal of Ginseng Research
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• 제20권3호
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• pp.331-338
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• 1996

This study was conducted to screen the antagonistic plants on northern root-knot nematode (Meloidogyne) and to utilize those in its control. Egg hatching of M. hapla was found to be inhibited by 17 plant methanol extracts, and 11 plant extracts among them were also toxic to M. hapla second stage juvenile. Egg hatching of iW. hapla was also found to be inhibited by squeezed extracts of Cassia tora and Zea mays, and they were also toxic to M. hapla second stage juvenile. Extracts of Achyranthes japonica, Melia axedrach and Acorus graminens were toxic to M. hapla second stage with a juvenile mortality above 70clc at the 10 folds diluted concent ration and A. graminens was toxic to tested juvenile mortality above 50% at the 100 folds diluted concentration. The toxicity was directly propotional to the diluted concentration of the plant extracts and to the exposure period. Punica granatum, Acorns graminens and Melia axedrach were effective in inhibiting root penetration of JW. hapla juveniles, among of them p. granatum is most effective Percent inhibition of penetration by second and third stage juveniles into tomato slants penetrating by it was 72.7 and 82.4%, respectively.

• Journal of Microbiology
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• 제39권2호
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• pp.133-138
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• 2001

We investigated the antagonism of indigenous bacteria isolated from stressed mussels and their extracellular metabolites on the adult zebra mussel, Dreissena polymorpha. Selective bacterial isolates including Aeromonas media, A. salmonicida, A. veronii, and Shewanella putrefaciens, showed strong lethality against adult mussels and 100% mortality was observed within 5 days of incubation. Bacterial metabolites, fractionated and concentrated from stationary-phase culture supernatants of these bacterial isolates, displayed varying degrees of antagonistic effects on zebra mussels. Among the three size fractions examined, <5, 5-10, and >10 kDa, the mast lethal fraction seems to be >10 kDa for three of the four isolates tested. Further chemical analyses of these size fractions revealed that the predominant constituents were polysaccharides and proteins. No 2-keto-3-deoxyoctanoic acid (2-KDO), deoxyribonucleic acids (DNA) or uranic acid were detectable. Extraction of supernatants of two antagonistic isolates with polar solvent suggested that polar molecules are present in the active fraction. Our data suggest that extracellular metabolites produced by antagonistic bacteria are also involved in disease development in zebra mussels and elucidation of the mechanisms involved may offer a novel strategy for control of biofouling invertebrates.