• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.293-296
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• 2014

This study was conducted to investigate the effect of culture temperature on the growth rate and protease activity of Antarctic microorganisms. The Antarctic microorganisms PAMC 25641, 25614, 25719 and 25617 were obtained from the Polar and Alpine Microbial Collection (PAMC) at the Korea Polar Research Institute. These microorganisms were confirmed for the excretion of protease on a plate with skim milk. The identification of microorganisms was carried out using the 16S rDNA sequencing method. PAMC 25641 showed the highest protease activity among the subjects tested, and PAMC 25617 exhibited the highest growth rate. The growth rates of the microorganisms were not affected by temperature, except for PAMC 25617. However, protease activities were increased for all strains in a temperature dependent fashion. These results suggest the possible application of Antarctic microorganisms for the efficient production of low temperature proteases.

• Korean journal of applied entomology
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• v.15 no.2 s.27
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• pp.61-68
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• 1976

Leading soybean cultivars such as Kwanggyo, Yugu No.3, Dongbugtae, Gangrim, and Eundaedu were heavily diseased by a virus in Korea. The disease was most severe in the northern provinces where soybean mosaic virus also occurrs, but the disease has also been observed in other provinces where soybean diseases are less prevalent. The disease symptoms were similar to bud blight caused by tobacco ringspot virus; but this was not confirmed in inoculation tests on indicator plants and serological experiments. There were some differences in varietal susceptibility to the disease, with symptom variation depending on the soybean cultivar and source of inoculm. Disease symptoms on infected soybean plants were mottling and necrosis. The present results, therefore, indicate some strains of SMV or a mixture of legume viruses may or may not be responsible for the disease.

• Biomedical Science Letters
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• v.24 no.3
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• pp.221-229
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• 2018

Trichophyton rubrum is one of the well-known pathogenic fungi and causes dermatophytosis and cutaneous mycosis in human world widely. However, there are not an available sequence type (ST) classification methods and previous studies for T. rubrum until now. Therefore, currently, molecular biological tools using their DNA sequences are used for genotype identification and classification. In the present study, in order to characterize the genetic diversity and the phylogenetic relation of T. rubrum clinical isolates, five different housekeeping genes, such as actin (ACT), calmodulin (CAL), RNA polymerase II (RPB2), superoxide dismutase 2 (SOD2), and ${\beta}$-tubulin (BT2) were analyzed using by multilocus sequence typing (MLST). Also, DNA sequence analysis was performed to examine the differences between the sequences of Trichophyton strains and the identified genetic variations sequence. As a result, most of the sequences were shown to have highly matched rates in their housekeeping genes. However, genetic variations were found on three different positions of ${\beta}$-tubulin gene and were shown to have changed from $C{\rightarrow}G$ (1766), $G{\rightarrow}T$ (1876), and $C{\rightarrow}A$ (1886). To confirm the association with T. rubrum inheritance, a phylogenetic tree analysis was performed. It was classified as four clusters, but there was little significant correlation. Even so, MLST analysis is believed to be helpful for determining the genetic variations of T. rubrum in cases where there is more large-scale data accumulation. In conclusion, the present study demonstrated the first MLST analysis of T. rubrum in Korea and explored the possibility that MLST could be a useful tool for studying the epidemiology and evolution of T. rubrum through further studies.

• International Journal of Oral Biology
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• v.39 no.2
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• pp.87-95
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• 2014

The purpose of this study was to isolate and identify bacteria from the 4 patients with non-odontogenic infectious lesions (mucormycosis, chronic inflammation from wound infection, and two actinomycosis) and determine their antimicrobial susceptibility against eight antibiotics. Bacterial culture was performed under three culture conditions (anaerobic, $CO_2$, and aerobic incubator). The bacterial strains were identified by 16S rRNA gene (16S rDNA) sequence comparison analysis method. For investigating the antimicrobial susceptibility of the bacteria against eight antibiotics, penicillin G, amoxicillin, tetracycline, cefuroxime, erythromycin, clindamycin, vancomycin, and Augmentin$^{(R)}$ (amoxicillin + clavulanic acid), minimum inhibitory concentration (MIC) measurement was performed using broth microdilution assay. Nosocomial pathogens such as Enterococcus faecalis, Klebsiella pneumoniae, Bacillus subtilis, and Neisseria flavescens were isolated from mucormycosis. Veillonella parvula, Enterobacter hormaechei, and Acinetobacter calcoaceticus were isolated from chronic inflammatory lesion. Actinomyces massiliensis was isolated from actinomycosis in parotid gland. Capnocytophaga ochracea was isolated from actinomycosis in buccal region in anaerobic condition. There was no susceptible antibiotic to all bacteria in mucormycosis. Tetracycline was susceptible to all bacteria in chronic inflammation. C. ochracea was resistant to vancomycin and penicillin G; and other antibiotics showed susceptibility to all bacteria in actinomycosis. The results indicated that the combined treatment of two or more antibiotics is better than single antibiotic treatment in mucormycosis, and penicillin is the first recommended antibiotic to treat actinomycosis.

• Journal of Ginseng Research
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• v.41 no.1
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• pp.36-42
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• 2017

Background: Some differences have been reported in the biotransformation of ginsenosides, probably due to the types of materials used such as ginseng, enzymes, and microorganisms. Moreover, most microorganisms used for transforming ginsenosides do not meet food-grade standards. We investigated the statistical conversion rate of major ginsenosides in ginsenosides model culture during fermentation by lactic acid bacteria (LAB) to estimate possible pathways. Methods: Ginsenosides standard mix was used as a model culture to facilitate clear identification of the metabolic changes. Changes in eight ginsenosides (Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, and Rg2) during fermentation with six strains of LAB were investigated. Results: In most cases, the residual ginsenoside level decreased by 5.9-36.8% compared with the initial ginsenoside level. Ginsenosides Rb1, Rb2, Rc, and Re continuously decreased during fermentation. By contrast, Rd was maintained or slightly increased after 1 d of fermentation. Rg1 and Rg2 reached their lowest values after 1-2 d of fermentation, and then began to increase gradually. The conversion of Rd, Rg1, and Rg2 into smaller deglycosylated forms was more rapid than that of Rd from Rb1, Rb2, and Rc, as well as that of Rg1 and Rg2 from Re during the first 2 d of fermentation with LAB. Conclusion: Ginsenosides Rb1, Rb2, Rc, and Re continuously decreased, whereas ginsenosides Rd, Rg1, and Rg2 increased after 1-2 d of fermentation. This study may provide new insights into the metabolism of ginsenosides and can clarify the metabolic changes in ginsenosides biotransformed by LAB.

• Food Science and Preservation
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• v.10 no.2
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• pp.224-229
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• 2003

This study was carried out to isolate of antagonistic bacterium to Allium cepa L. pathogens. A total of 250 strains were isolated from A. cepa L. roots. The isolates were screened for antagonism to A. cepa L. pathogens and the isolated strain No. YJ-4 was selected among these bacteria. It was identified as Bacillus ehimensis based on morphological and physiological characteristics according to the Bergey's mannual of systematic bacteriology, Sherlock system of Microbial ID Int and 165 rDNA sequences methods. Bacillus ehimensis YJ-4 showed broad spectrum of antibacterial and antifungal activities against plant pathogens as Alternaria porri, Botrytis cinerea, Erwinia carotovora subsp. carotovora Fusarium of oxysporium, penicillium sp., Pseudomonas sp., Rhizoctonia solani, Sclerotium cepivotum, Septoria sp., Stemphylium botryosum. Speially B. ehimensis YJ-4 showed high antifungal activity on growth against F. oxysporium, the causal agent of onion Fusarium wilt.

• Journal of Life Science
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• v.9 no.3
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• pp.289-292
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• 1999

This study was performed to monitor the circulation of various influenza virus strains since influenza is one of the commonest respiratory disease in man, its causative virus has been the subjects of extensive research. The authors investigated the epidemics of influenza in Pusan in 1998. Influenza viruses have been isolated from patients with respiratory disease whose ages range from 1 to 68. Virus isolation from female was higher than male. The isolation of virus was mostly concentrated in December in 1998. The isolated virus showed strong cytopathic effect on MDCK cells and identified as influenza A/Sydney/05/97-like(H3N2) and influenza A/Beijing/262/95-like(H1N1). A negative staining of electron micrograph showed 130 nm with H1N1 in diameter, respectively.

• Journal of Life Science
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• v.13 no.6
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• pp.843-848
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• 2003

Diarrllea and death of chicken have been brought about by fowl typhoid caused by Salmonella gallinarum, which causes a great loss of chicken farms. For the development of the probiotic which can control a fowl typhoid of S. gallinarum without any adverse effect of commercial existing antibiotics, we isolated antagonistic intestinal bacteria against S. gallinarum from a bowel of the chicken which was pastured in a chicken farm of Gumi, Kyoungbuk. An Y3 strain which had a strong antagonistic ability to S. gallinarum was selected as a candidate of chicken probiotic microorganism among isolated strains. It was identified as a Bacillus amyloliuefaciens by 98% similarity by the result of cultural, physiological, biochemical test and Biolog system$(Microlog^{TM} 4.0)$, and named as Bacillus amyloliquefaciens Y3. The strain showed the strongest antagonistic activity and a good growth at pH 5-9, $37^{\circ}C.$

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.703-712
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• 1998

Physicochemical factors, microbial population size and the properties of the bacterial isolates were estimated to find out the nature of soil ecosystem of Mt. Nam. Samples were obtained from the surface layer of soils on which specific plant community is developed. Average content of moisture and organic matter of the soils were 21.6% and 17.3%, respectively. These values were similar to those of developing forest soils, but were slightly lower than those of climax ecosystem such as Piagol in Mt. Chiri. Chiri. Content of phosphate was higher than those of other forest soils. The population size of soil bacteria ranged from 27.4 to 195.8 ${\times}\;10^5$ CFU/g. duy soil, and the size is somewhat dependent on the moisture and oranic matter content of soils. A large number of bacteria were able to decompose macromolecules such as starch, elastin and gelatin. Bacterial species composition of each soil was comparatively simple. Pseudomonas, Agrobacterium, Flavobacterium and Xanthomonas which are Gram-negative short rods were widely distributed in the forest soils. The endospore forming Bacillus species were also the main constituents of the soil microflroa. Actinomycetes were widely distributed in the forest soils, but the distribution pattern varied in each site. Most of the actinomycetes were also able to decompose organic macromolecules. The rate of resistant actinomycete strains to antibiotics and heavy metals were lower than those from cultivated soils, but higher than those from well-preserved forest soils. Antibiosis pattern of the actinomycete isolates was similiar to the resistance pattern. This means the forest soils of Mt. nam was somewhat interferred by artificial behabiour.

• Journal of Ecology and Environment
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• v.29 no.4
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• pp.399-404
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• 2006

This study was carried out to investigate the population densities, R/S ratios, and identification of heterotrophic bacteria on the rhizosphere soil of halophyte Suaeda japonica found on the western and southern mudflats of Korea. The population densities of aerobic and anaerobic heterotrophic bacteria on the rhizosphere soil of Suaeda japonica were in the range of $1.3\;{\pm}\;0.3\;{\times}\;10^6\;{\sim}\;6.3\;{\pm}\;3.3\;{\times}\;10^7\;and\;2.8\;{\pm}\;1.3\;{\times}\;10^4\;{\sim}\;1.8\;{\pm}\;0.7\;{\times}\;10^7\;cfu\;g^{-1}\;d.\;wt.$, respectively. In case of physiologically specific bacteria, population densities of amylolytic bacteria on the rhizosphere soil of Suaeda japonica were in the range of $4.4\;{\pm}\;0.6\;{\times}\;10^6\;{\sim}\;2.5\;{\pm}\;1.2\;{\times}\;10^7\;cfu\;g^{-1}\;d.\;wt.$, those of cellulolytic bacteria were from $8.5\;{\pm}\;6.0\;{\times}\;10^4\;{\sim}\;2.3\;{\pm}\;1.6\;{\times}\;10^6\;cfu\;g^{-1}\;d.\;wt.$, and those of proteolytic bacteria were from $3.8\;{\pm}\;1.8\;{\times}\;10^5\;{\sim}\;4.2\;{\pm}\;2.9\;{\times}\;10^6\;cfu\;g^{-1}\;d.\;wt.$, respectively. The R/S ratios were ranged from 2.33 to 2.39. Among eleven isolates from the roots of halophyte Suaeda japonica of Goheung bay by using 16S rDNA analysis, five clones were closely related to ${\gamma}-Proteobacteria$ group and six clones were closely related to ${\alpha}-Proteobacteria$ group. Among four isolates from Suncheon bay, two strains were related to ${\gamma}-Proteobacteria$ group and another two were related to Actinobacteria and Bacilli group, respectively.