• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.205.2-205
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• 1978

우리나라 전국명지에서 약 1400여점의 토양시료를 채취하여 이 토양 시료에서 방사선균 1635균주를순수분리 배양하고, 명 균주를 배양하여 생산되는 항생물질 중 paper disk method에 의해 벼문고 병균 Pellicularia sasakii에 대한 항균력을 나타내는 균주를 선발하고, 이차선발로서 Dendroid test method와 최종적 선발방법으로 벼를 대상으로 문고병 발생에 대한 green house test에 의하여 우수한 균주를 취득하였다.

• The Korean Journal of Mycology
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• v.42 no.1
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• pp.57-63
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• 2014

This study was carried out to obtain morphological and physiological characteristics of ear mushrooms for an artificial cultivation. Eighteen strains were cultivated with bag culture and classified into mainly five groups such as brown, black, white, purple and others group. The highest yield was shown in 43007 strain as 98.3 g/bag and 43009, 43016, 43025 and 44035 strains were more than 60 g/bag. Among collected strains, 43007, 43009 and 43035 were selected in this study as superior strains. Three selected strains were investigated for optimal mycelial growth conditions. MCM and GPYM media were selected for the favorable culture medium. The carbon sources of 43007, 43009 and 43035 on mycelial growth were maltose, fructose and glucose, respectively and peptone was selected as a nitrogen source. Highest mycelial growth was observed when the C/N ratio was 10 for 43007 and 20 for 43009 and 43035.

• Journal of Mushroom
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• v.2 no.1
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• pp.33-37
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• 2004

To develop neohaplonts for Ganoderma breeding, protoplasts were isolated from dikaryotic mycelium and regenerated. Selection rate of neohaplonts varied between ASI7074, ASI7091, ASI7094, ASI7100 and ASI7115, showing 5.24% on the average. Auxotropic mutants from Ganoderma monokarions were recovered by UV irradiation on protoplasts. Protoplast survival rates were 1.9% ASI 7074, 0.17% ASI 7091, and zero percent ASI 7100 using 300 second irradiation. Four auxotrophic strains were recovered from 1,536 colonies screened that will be further utilized for protoplast fusion and transformation.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.463-475
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• 2018

Salinity and extreme temperature stresses affect growth and productivity of crops negatively. Beneficial bacteria, including plant growth-promoting rhizobacteria (PGPR) induce growth promotion and tolerance of plants under abiotic stress conditions. In the present study, 20 strains were selected from 1944 isolated bacteria based on three plant growth-promoting (PGP) traits-aminocyclopropane-1-carboxylate deaminase activity, phosphate solubilization, indole-3-acetic acid production, and growth ability under salinity and extreme temperature stress conditions. Seven among the 20 strains were selected based on growth-promoting effects on plants under saline or temperature stresses in tomato plants. It was expected that the seven strains could induce tolerance of tomato plants under salinity or extreme temperature stresses, which implies that these seven strains can act as potential inducers of multiple stresses tolerance in tomato plants.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.300-307
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• 2015

For selecting Bacillus strains producing high-quality Cheonggukjang, 8 strains were isolated from the different Cheonggukjang samples. Seven of them exhibited the highest 16S rRNA gene sequence similarity value of over 99.9% to Bacillus subtilis subsp. subtilis and one of them showed the similarity to B. licheniformis. All the strains showed positive activities for amylase, cellulase, protease and lipase, and 6 strains are positive for fibrinolytic activity. To confirm the safety of the strains isolated from the samples of Cheonggukjang which are manufactured by traditional method, strains were analyzed for the presence of seven toxin genes of Bacillus cereus and results were found negative. And 7 strains did not produce at all or merely produce both histamine and tyramine, the representative biogenic amines. Biogenic amine degradation analysis by HPLC revealed that, most of them exhibited tyramine degradation activity. For Cheonggukjang fermented by artificial inoculation of selected strains, fermentation property, sensory test, volatile basic nitrogen production and metabolic profiles by $^1H-NMR$ were tested. Seven strains were confirmed to make high-quality Cheonggukjang.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.103-108
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• 2022

This study investigated the strains and fermentation characteristics of used to ferment a mixture of rice and soybeans to manufacture low-salt doenjang for flavoring. The soybean and rice mixture was fermented using three selected strains of Aapergillus oryzae and Bacillus sp. The changes in quality of the fermented products were found to be dependent on the aging period. Therefore, the strain and a suitable aging period were seleted based on the increases in AN, total sugar, and reducing sugar. The fermented products were prepared and mixed, using the selected or commercially available strains (the sample and control, respectively), to create low-salt doenjang. Following this, their characteristics were compared. The sample had a higher content of taste-related ingredients(free amino acid, nucleic acid-related substances) than the control. Using the selected strain to ferment a rice and soybean mixture will thus be expected to enhance the flavor of industrially produced seasoned doenjang.

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.33-40
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• 1996

우리나라 여러 딸기 재배지에서 전형적인 시들음 증상을 나타내는 이병식물에서 분리한 32개의 Fusarium oxysporum 균주들을 vegetative compatibility와 전기영동에 의한 동위효소상의 차이에 의해 분류하고 이들과 병원성과의 관계를 알아보았다. Nitrate nonutilizing(nit) mutant를 이용하여 vegetative compatibility group으로 분류해 본 결과 크게 A, B, C, D의 4개 그룹으로 나눌 수 있었으며 A그룹에는 15개 균주, B그룹에는 7개 균주, C와 D그룹에는 각각 2개 균주, 그리고 single VCG인 6개 균주가 존재하였다. 전기영동에 의한 esterase, catalase, acid phosphatase, leucin-aminopeptidase(LAP)의 동위효소상을 비교하여 본 결과 I, II, III, IV의 4개 그룹으로 나눌 수 있었으 I 그룹에는 18개 균주, II그룹에는 2개 균주, III그룹에는 6개 균주, IV그룹에는 6개 균주로 분류할 수 있었다. 또한, VCG의 A와 D그룹에 속하는 모든 균주들의 동위효소상의 I 그룹에 속하였으며 VCG B그룹의 7개 균주들 중에서 5개 균주가 동위효소상의 IV그룹, 7개 균주들 중에서 5개 균주가 동위효소상의 IV그룹, 나머지 2개 균주는 I 그룹과 III 그룹에 속하였으며 C그룹의 균주는 III과 IV 그룹에 속하였고, single VCGs들은 III 그룹에 4개 균주, II 그룹에 2개 균주가 속하므로 VCG와 동위효소상 간에는 밀접한 관계가 있음을 알 수 있었다. 4개 딸기 품종에 대해 병원성을 비교하여 본 결과 VCG A에서 선발된 2개 균주들은 보교조생에 대해 가장 병원성이 강하였으며 정보나 여홍에 대해서도 강한 병원성을 가지고 있었다. 반면에 B 그룹에서 선발된 2개 균주들은 4개 품종에 대해 병원성이 약하거나 거의 없었으며 C 그룹에서 선발된 1개 균주는 여홍에 대해 상대적으로 가장 강한 병원성을 가지고 있었다.

• Research in Plant Disease
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• v.16 no.2
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• pp.158-162
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• 2010

Four promising biocontrol agents against Phytophthora capsici were selected from 507 bacterial isolates collected from rhizosphere soils and roots of pepper plants. In vitro experiment, these four biocontrol agents inhibited mycelial growth, germination of cystospores, and formation of zoosporangia and zoospores of Phytophthora capsici. In the pot experiment, the four biocontrol agents showed control efficiency higher than 70%. In greenhouse experiment, the isolates G28-6 gave the control value of 79.4%. These four biocontrol agents successfully colonized in the population density beyond 105 cfu/g on roots of pepper in vitro. The isolates G28-6 was identified as Pseudomonas aurantiaca, based on its cultural, morphological, and biochemical characterization and 16S rRNA gene sequence analysis.

• KSBB Journal
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• v.14 no.2
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• pp.146-152
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• 1999

Screening experiments were carried out in order to select bacteria causing brown blotch disease on the mushroom, Pleurotus ostreatus. Four bacteria causing brown blotch disease were isolated from Pleurotus ostreatus and soils around the mushroom farm. Three strains showing antagonism against brown blotch causing bacteria, A-11, A-20 and A-29 were also isolated through methods pitting test, cross checking and biochemical test, and identified as Pseudomonas fluorescence for A-11 and A-20, and Pseudomonas sp. for A-29, respectively. Colonial morphology test also showed that A-11 and A-29 were appeared as transparent gel with green color, whereas the colony of A-20 showed opaque gel with light green color.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.268-275
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• 2008

In order to develop the multi-functional rhizobacteria that can exert positive effect on the growth of plants growing in the coastal sand dune located along East Coast of Korea, rhizospheral bacteria of 11 different plants from this area were isolated 1,330 rhizobacteria. Among these, 23 strains were able to produce auxin and had spectrum of antagonism toward various phytopathogenic microbes. To know the mechanism of this antifungal activity, these 23 strains were subjected to further analyses; 19 strains of these produced siderophore as determined by color reaction on CAS-blue plate, 4 strains produced antifungal cellulase as judged by color change on CMC-Congo red plate, 17 strains were able to utilized insoluble phosphate salts, also determined by clear zone formation on PVK medium. Identification of the strain was assigned to all 23 strains by l6s rDNA sequence analysed, and all were identified to be in the genus of Bacillus and Pseudomonas. One strain of these, denoted Pseudomonas fluorescens IB4-14, showed ACC deaminase activity which is known to be involved in the resistance of environmental stress such as salt and drought. Also, P. fluorescens IB4-l4 showed the germination stimulation and roots growth promoting activity on the in vivo assay of Lysimachia mauritiana Lam. (spoonleaf yellow loosestrife).