• 한국식물병리학회지
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• 제3권3호
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• pp.168-173
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• 1987

도열병균(Pyricularia oryzae) 균사체의 esterase 동위효소 pattern이 배양조건에 의하여 변화되는가를 $10\~25\%$ polyacrylamide gradient slab gel을 사용하여 알아보았다. 배양기간에 따라 배양 24일까지 동위효소 pattern은 변하지 않았지만 특징 band의 효소량에는 차이가 있었다. 탄소원(glucose, fructose, maltose, sucrose, starch), 단포자분리균주간, 계대배양 및 세포벽재생균주간의 동위효소 pattern은 변함이 없었다.

• 한국미생물·생명공학회지
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• 제49권2호
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• pp.217-224
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• 2021

Rice blast caused by Pyricularia oryzae, which is a major threat to food security worldwide, markedly decreases the yield of rice. Some rhizobacteria called 'plant growth-promoting rhizobacteria' inhibit plant pathogens and improve plant growth by secreting iron-chelating siderophores. The decreased availability of iron adversely affects the survival of pathogens, especially fungal pathogens, in the rhizosphere. This study aimed to determine the morphological diversity of siderophore-producing bacteria, analyze the type of siderophores produced by the bacteria, and examine their growth-inhibitory activity against Pyricularia oryzae. The rhizobacteria were isolated from the rhizosphere of Sembada Hitam variety of black rice plants in Pakem, Sleman, Yogyakarta, Indonesia. In total, 12 distinct isolates were screened for the production of siderophores. It was found that 9 out of 12 bacteria produced siderophore and most of them were Gram positive bacteria. The best siderophore-producing isolates with different type of siderophore were used in further studies. The IS3 and IS14 isolates were found to be the best siderophore producer that produced hydroxamate and mixed type of hydroxamate-carboxylate type of siderophore, respectively. In the dual culture assay, IS14 showed a strong antagonistic effect against Pyricularia oryzae by the 81.17% inhibition.

• 미생물학회지
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• 제23권3호
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• pp.209-214
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• 1985

The optimum conditions of protoplasts formation from Pyricularia oryzae were investigated with lytic enzymes and osmotic stabilizers. The mycelia were begun to refease the protoplasts in response to the complex enzyme solution after 30-60 minutes and reached to maximum after 2-3hrs. Among the lytic enzymes tested, the mixture solution containing ${\beta}-Glucuronidase$(0.01 ml/ml), Cellulase ONOZUKA-RS(20mg/ml), Driselase (10mg/ml), and Macerozyme R-10 (10mg/ml) resulted in the highest rate of protoplasts releasing of Pyricularia oryzae. The best stabilizer was 0.6M KCl at pH 7.0. Shen the mycelia were digested with enzyme mixture, the stationary culture was better than shaking culture for higher protoplast formation.

• Fisheries and Aquatic Sciences
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• 제5권2호
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• pp.97-102
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• 2002

Pyricularia oryzae (P. oryzae), the cause of rice blast, is one of the most important fungal pathogens of rice. Seventy strains of marine fungi were isolated from marine algae, and it was measured antifungal activity against P. oryzae. Metabolites of marine fungus A-248 which isolated from marine algae showed strong antifungal activity against P. oryzae. The antifungal substance from the metabolites of marine fungus A-248 was extracted with ethylacetate, and then purified by preparative TLC and reverse-phase HPLC. The minimum inhibitory concentration (MIC) value was $0.18\mu g/mL$ for the antifungal activity of the substance purified from A-248 metabolites. The purified substance was similar to antifungal activity of rhizoxin, which is a commercial antifungal agent.

• 한국응용곤충학회지
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• 제11권2호
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• pp.101-107
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• 1972

벼 이삭마름병해에 관여하는 균류와 이들 균류에 대한 약제별 살균효과를 알고저 시험한 결과를 요약하면 다음과 같다. 1. 일반 장려품종 및 통일품종의 변색된 벼알에서 균류를 조사한 결과 일반 장려품종에서는 Pyricularia oryzae, Helminthosporium oryzae, Epicoccum purpurascens, Curvularia lunata, Cladosporium cladosporoides, Alternaria tenuis균 등이 주로 많이 검출되었고 통일 품종에서는 Trichoconis padwickii, Fusarium dimerum, Nigrospora oryzae균 등이 많이 검출되었다. 2. 벼 이삭도열병에 이병된 이 삭의 각 부위로부터 균류를 조사한 결과 이삭목에서는 Pyricularia oryzae, Nigrospora oryzae, Curvularia lunata 균등이 이삭가지에서는 Helminthosporium eryzae, Trichoconis padwickii, Stemphylium sp., Cladosporium cladosporoides, Alternaria tenuis균 등이 많이 검출되었으며 벼알에서는 Phema spp. 균이 주로 많이 검출되었다. 3. 각종 균류에 이병된 이삭가지 및 벼 알에서의 Difolatan 수화제, Dithane M-45 수화제의 살균효과를 실내에서 시험한 결과 Difolatan 800배 액은 Helminthosporium oryzae, Cladosporium cladosporoides, Alternaria tenuis 균 등에 살균효과가 좋았고 Dithane M-45 500배 액은 Pyricularia oryzae, Trichoconis padwickii, Curvularia lunate 균등에 비교적 효과가 좋았다. 4. 약제 방제시기는 유숙기살포구, 출수개화기살포구의 순으로 효과가 좋았으며 약제별 방제효과는 본 시험포장에 이삭도열병 발생이 많았던 관계로 도열병 방제 약제인 히노산유제, 가스가민유제가 Difolatan 수화제, Dithane M-45 수화제에 비하여 다소 효과가 좋은 것으로 나타났다.

• 한국미생물·생명공학회지
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• 제17권4호
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• pp.307-312
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• 1989

77-AG-567 균주는 Pyricularia oryzae와 Sphasrotheca fuliginea에 대한 항균활성을 나타냈다. 활성 물질을 정제해 가는 과정에서 이 균주는 blasticidin S와 또 다른 항생물질을 동시에 생산한다는 사실을 알았다. 이 화합물은 UV 및 $^1$H NMR 스펙트럼에 의해 E-73이라고도 일컬어지는 acetoxycycloheximide로 밝혀졌다. 균주를 동정해본 결과 77-AG-567균주는 Streptomyces atbutus로 판단되며 지금까지 blasticidin S와 acetoxycycloheximide를 동시에 생산하는 것으로 알려져 온 S. albulus와는 다른 특성을 나타냈다. 특히 주목할만한 차이점은 포자의 표면이였다. 또한 acetoxycycloheximide는 지금까지 효모와 종양세포에만 생리활성을 나타내는 것으로 알려져 왔으나 본 실험결과 Pyricularia oryzae와 Sphasrotheca fuliginea에도 항균활성을 가진다는 사실을 알았다.

• Journal of Microbiology and Biotechnology
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• 제13권6호
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• pp.984-988
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• 2003

The actinomycete strain KH-6l4 possessed strong antifungal activity, especially antagonistic to the rice blast fungus, Pyricularia oryzae. Diaminopimelic acid (DAP) type and morphological and physiological characteristics, examined by scanning electron microscopy (SEM), indicated that KH-614 belonged to the genus Streptomyces. Antifungal agent produced by this strain was found to be most active, when the strain was cultured in the presence of glucose, polypeptone, and yeast extract (PY) medium for 6 days at $27^{\circ}C$. Based on the spectral report data, MS and NMR, the antifungal agent was identified as cyclo(L-leucyl-L-prolyl). According to the antimicrobial activity test measured by minimal inhibitory concentration (MIC), the cyclo(1eu-pro) exhibited the activity against Candida albicans IAM 4905, Mucor ramannianus IAM6218, Rhizoctonia solani IFO 6218, Aspergilus fumigatus ATCC 42202, Glomerella cingulata IFO 9767, Trichophton mentagrophytes ATCC 18749, and Trichophyton rubrum ATCC 44766, the order of MIC values were 50, 12.5, 5, 50, 25, 5, $5\;\mu\textrm{g}/ml$, respectively. Specifically, cyclo(1eu-pro) was one of the most effective elements against Pyricularia oryzae IFO 5994 with the MIC value of $2.5\;\mu\textrm{g}/ml$, thus indicating that cyclo(leu-pro) is a potential antifungal agent.

• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.811-816
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• 2000

An antagonistic bacterium PM-1 which strongly inhyibits the growth of Pyricularia oryzae was isolated and identified as paenibacillus macerans. The antifungal substances of the strain PM-1 showed the broad antifungal spectra against P.oryzae races. Relating to the localization test, it was found that the antifungal substances existed not only in the cytoplasm but also in the culture supernatant, and importantly the antifungal activity of the latter was stronger than that of the former. The extracellular antifungal substances were extremely heat-stable up to $121^{\circ}C$ for 15 min. The substances were optimally produced at $20^{\circ}C$ and pH 10.0 in a potato dextrose broth. The culture filtrate of the strain PM-1 caused a partial swelling of the mycelia of P.oryzae, and it prevents the normal growth of the fungus as well. This result suggested that the antifungal substances secreted by the strain PM-1 potentially inhibited the germination of P.oryzae.

• 한국식물병리학회지
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• 제3권2호
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• pp.124-130
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• 1987

수도 도열병균(Pyricularia oryzae)의 균사체로부터 다량의 원형질체의 분리 및 세포벽 재생을 하기 위하여 필요한 몇가지 조건을 선발하였다. 나출을 위하여 기본용액으로 0.02M potassium phosphate buffer와 pH 5.2, 0.6M KCl로 삼투압을 조절하였고 분해효소는 ml당 각각 20mg Cellulase R-10, 5mg Macerozyme $-10, 10mg Driselase를 사용하였는데 각각의 단독처리구보다 3가지 효소의 복합처리구에서 원형질체 나출 정도가 우수하였다. 또한 선발된 복합효소액에 2일간 액체배양된 어린 균사체를 3시간, $30^{\circ}C$ 항온기에서 진탕했을 때 가장 많은 원형질체가 분리되었다. 원형질체로부터 세포벽의 재생은 순수 정제한 원형질체를 0.2M potassium phosphate와 0.6M KCl을 삼투압을 조절한 감자한철배지에 접종시켜 가장 높은 재생율을 얻을 수 있었다.

• 한국미생물·생명공학회지
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• 제25권6호
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• pp.537-545
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• 1997

The aim of the present research program was to isolate a strain of actinomycetes producing antifungal substance. Soil samples were collected from various sites in Korea and a number of actinomycetes were isolated from the soil samples by applying selective agar for actinomycetes. Among isolates, a strain (NA -52) producing antifungal substance against Pyricularia oryzae was selected. Chemotaxonomic and numerical identification were carried out for the isolate. Fifty taxonomic unit characters were tested and the data were analyzed numerically using TAXON program. The isolate was identified as a synonym of streptomyces diastaticus belong to cluster No. 19 (Streptomyces diastaticus). But it showed a low similarity to S. diastaticus in simple matching coefficients, hence it was considered as one new species in Streptomyces.