• Journal of Korean society of Dental Hygiene
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• v.1 no.2
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• pp.193-200
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• 2001

An appropriate amount of samples, collected from three each paddy forest, field and riverside soil near Taegu city, was suspended in sterile water and then diluted in order to isolation of antagonistic to oral cancer. The diluted samples were inoculated on separating medium in the routing spreading method. So, seven hundred and eighteen strains were isolated on HV agar and 220 strains were on methanol medium from soil samples. So, during the screening of anti-oral cancer activity from soil, we isolated microorganisms showing powerful antagonistic activity. Among them, No. 78 strain exhibited the most strongly anti-oral cancer activity. Microbiological properties were investigated by the methods described in the Bergey's Manual of Systematic Bacteriology and experimental methods of identification of actinomycetes by Hamada et al. As a result, a methylotrophic actinomycetes strain No. 79 was estimated as Amycolatopsis sp. based on taxonomic studies.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.115-120
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• 1989

For the purpose of obtaining microorganisms which produced an extracellular pepsin inhibitor, screening test was carried out. One strain of Actinomycetes (GF 155-2) isolated from soil samples showed a high inhibitory activity against porcine pepsin. The morphological, physiological and cultural characteristics of the strain GE 155-2 on various culture media were studied according to ISP methods and Bergey's manual of determinative bacteriology (8th ed.). This Actinomycetes GE 155-2 was found to be similar to the genus Microtetraspora.

• BMB Reports
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• v.31 no.5
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• pp.475-483
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• 1998

Many antibiotics contain partially deoxygenated sugar components that are usually essential for biological activity, affinity, structural stability, and solubility of antibiotics. Gene probes of the biosynthetic genes related with the deoxysugar were obtained from PCR. Primers were designed from the conserved peptide sequences of the known dTDP-D-glucose 4,6-dehydratases, which are the key step enzymes in the biosynthesis of deoxysugar. The primers were applied to amplify parts of dehydratase genes to 27 actinomycetes that produce the metabolites containing deoxysugar as structural constituents. About 180 and 340 bp DNA fragments from all of the actinomycetes were produced by PCR and analyzed by Southern blot and DNA sequencing. The PCR products were used as gene probes to clone the biosynthetic gene clusters for the antibiotic mithramycin, rubradirin, spectinomycin, and elaiophyrin. This method should allow for detecting of the biosynthetic gene clusters of a vast array of secondary metabolites isolated from actinomycetes because of the widespread existence of deoxysugar constituents in secondary metabolites.

• Microbiology and Biotechnology Letters
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• v.22 no.2
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• pp.222-225
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• 1994

Three kinds of pretreatment methods were used for selectivel isolation of soil actinomy cetes. One hundred and six strains were isolated on Bennet's agar and 114 strains were on humic acid-vitamin agar from 5 domestic soil samples. All of these isolates were identified to the genus level based on morphological and physiological characheristics. Among three methods, dry heat was most effective to isolate many different strains including rare actinomycetes. On genus, Bennet's agar was effective for selective isolation of Nocardia but bumic acid-vitamin agar for another rare actinomycetes.

• Korean Journal of Microbiology
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• v.38 no.2
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• pp.139-143
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• 2002

To find $\alpha$-glucosidase inhibitors produced by Actinomycetes, bacteria belonging to Actinomycetes were isolated from soil sample using Bennett's medium. The inhibitory activity induced by these bacteria on $\alpha$-glucosidase, which is the key enzymes far carbohydrates digestion and the prevention of diabetic complications, was investigated. A strain of these bacteria, PM718 potently inhibited $\alpha$-glucosidase activity in vitro.

• YAKHAK HOEJI
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• v.35 no.3
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• pp.245-251
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• 1991

Selective culture of actinomycetes from soil microbes and their antibiotic producing characters by agar-disk method were examined. Some of the organisms which produced antibiotics on agar disk did not produce antibiotics in liquid culture. Further examination indicated that production of antibiotic was dependent on the composition of medium. Many streptomycestes produced antibacterial substances in tryptic soy broth but others produced antifungal antibiotics in V-8 broth. Production of antibacterial substances by Streptomyces sp. was also dependent on the medium composition.

• Environmental Engineering Research
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• v.10 no.2
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• pp.79-87
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• 2005

The effects of transformation capacity on cometabolic degradation of trichloroethene (TCE) were evaluated using TCE-degrading actinomycetes pure and mixed culture under various culture conditions. The TCE transformation capacity of the actinomycetes enrichment culture in a batch test with phenol addition was 1.0 mg of TCE/mg of volatile suspended solids (VSS). The resting cell TCE transformation capacity of the actinomycetes pure culture cell was 0.75 mg TCE/mg VSS, which increased to 2.0 mg TCE/mg VSS when phenol was added as an external substrate. When the pure culture had an internal substrate in the form of poly-β-hydroxybutyrate (PHB) at 19% of the cell mass, the resting cell TCE transformation capacity increased from 0.47 to 0.6 mg TCE/mg VSS. The presence of PHB increased transformation capacity by 57%, whereas, the addition of phenol caused more than two fold increase in transformation capacity. The actinomycetes culture showed the highest transformation capacity.

• Journal of Microbiology and Biotechnology
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• v.7 no.2
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• pp.95-100
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• 1997

• Mycobiology
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• v.48 no.1
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• pp.37-43
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• 2020

A serious leaf disease caused by Colletotrichum dematium was found during the cultivation of Sarcandra glabra in Jingxi, Rong'an, and Donglan Counties in Guangxi Province, which inflicted huge losses to plant productivity. Biological control gradually became an effective control method for plant pathogens. Many studies showed that the application of actinomycetes in biological control has been effective. Therefore, it may be of great significance to study the application of actinomycetes on controlling the diseases caused by S. glabra. Strains of antifungal actinomycetes capable of inhibiting C. dematium were identified, isolated and screened from healthy plants tissues and the rhizospheres in soils containing S. glabra. In this study, 15 actinomycetes strains were isolated and among these, strains JT-2F, DT-3F, and JJ-3F, appeared to show antagonistic effects against anthracnose of S. glabra. The strains JT-2F and DT-3F were isolated from soil, while JJ-3F was isolated from plant stems. The antagonism rate of strain JT-2F was 86.75%, which was the highest value among the three strains. Additionally, the JT-2F strain also had the strongest antagonistic activity when the antagonistic activities were tested against seven plant pathogens. Strain JT-2F is able to produce proteases and cellulase to degrade the protein and cellulose components of cell walls of C. dematium, respectively. This results in mycelia damage which leads to inhibition of the growth of C. dematium. Strain JT-2F was identified as Streptomyces tsukiyonensis based on morphological traits and 16S rDNA sequence analysis.

• KSBB Journal
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• v.22 no.4
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• pp.218-221
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• 2007

The polyene antifungal antibiotics, mostly produced by Gram-positive soil actinomycetes, are a family of type I polyketide macrolide ring compounds with 20$\sim$40 carbon backbone contain 3$\sim$8 conjugated double bonds. Using polyene-specific genomic screening strategy, we previously isolated three novel polyene-producing actinomycetes strains from soil, implying the potential application of these strains' spores as microbial pesticides. Here, we report that the sonication is a very efficient method for actinomycetes spore generation with a sonicator power-dependent manner. In addition, these sonication-driven actinomycetes spores retained significant portion of their cell viabilities as well as antifungal activities after freeze-drying procedure, implying the potential application of these strains' spores as microbial pesticides.