• Korean Journal of Microbiology
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• v.25 no.2
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• pp.137-143
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• 1987

Dominant genera of heterotrophic bacteria were investigated seasonally in Kum River estuarine sediments. Numerical taxonomy on the isolated heterotrophic bacteria were carried out according to their morphological, physiological, nutritional and biochemical characters. Heterotrophic bacteria in the depths of 0 to 10 cm of sampled sediments were almost facultative anaerobes, and 77.9% to 86.9% of them were Gram negative rods. Kominant genera among the isolates were Pseudomonas, Flavobacterium, Micrococcus, Cnterobacteria and Vibrio during sampling periods. According to their character analyses by similarity index(S), the isolates were clustered in fourteen groups at clay type sediments (Site 1) and four groups at sand type sediments (Site 2).

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.129-134
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• 2005

The monthly variations of physico-chemical and microbiological water quality were investigate in the artificial Lake Geumgang near estuary barrage. Sixty heterotrophic bacteria were isolated and identified by amplification and sequencing of 16S rDNA. Water temperature, pH, and inorganic nutrients($NH_4$-N, $NO_2$-N, $NO_3$-N, $PO_4$-P) were measured. Concentrations of DO, BOD, and inorganic nutrients were lower than in the middle-stream of Geum river The population densities of heterotrophic bacteria and total coliforms varied from $4.1{\pm}1.0\times10^2$ to $6.7{\pm}1.1{\times}10^3\;cfu\;ml^{-1}$, and 0 to $2.3{\pm}0.6{\times}10^2\;cfu\;ml^{-1}$, respectively. Among the measured numbers of physiological groups of bacteria, cellulolytic bacteria showed higher population densities than those of other physiological groups. Bacterial community structure was analysed based on 16S rDNA partial sequencing. Among 60 isolates, dominant genus was Pseudomones (20 strains).

• Korean Journal of Microbiology
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• v.26 no.3
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• pp.256-261
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• 1988

Samples from Naktong Estuary had been taken for the characterization of heterotrophic bacterial communities and of the effects of environmental factors on their distribution in estuarine ecosystem. Bacterial communities isolated from seawater region were composed of more euryhalone groups than those from freshwater region, and the bacterial communities of summer were composed of more eurythermal groups than those of winter. Bacterial commnities became more diverse by the input of allochthonous bacteria from terrestrial and freshwater ecosystem, but less diverse by worse environmental conditions such as nutrient load, high salinity, low temperature, and so on.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.265-271
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• 1989

Bacteria isolated from Cheonsu Bay at 4 seasons were analyzed by numerical taxonomic method. Results of 48 morphological, physiological and biochemical tests showed different adaptability of bacteria to temperature in consequence with sampling season and isolated bacteria were able to survive at various environmental conditions, Identification results revealed that Enterobacteriaceae, Aeromonas, Pseudomonas and Vibrio were dominant genera in geterotrophic bacterial community. For each season, Aeromonas was most dominant in spring and autumn, Pseudomonas and Enterobacteriaceae in summer and winter, respectively. Cluster ananlysis was performed and all vacteria were clustered into 29 phenetic groups. Seasonal characteristics were distict in each group. Different physiological characteristics and species compositions for each season contribute to the stability and diversity of environmental ecosystem.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.272-278
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• 1989

The bacteria utilizing 3-chlorobenzoate as a sole carbon and energy source were isolated by Most-Probable-Number technique and identified in Korean coastal waters. Pseudomonas, Moraxella and Flavobacterium were dominant genera and comprised 70.2% of total isolates. Forty-four biochemical, cultural, morphological and physiological testa were performed and average linding cluster analysis was conducted from the test results. Total 92.7% of isolates were clustered into 17 groups under the 80% similarity level. The degradation of 3-chlorobenzoate was performed by many heterogeneous bacteria and the species diversity of these bacterial group offers informations of the stability of bacterial communities in relation to carbon compound cycling in coastal enviromnents.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.3
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• pp.267-272
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• 2015

The purpose of this study was to examine the antiobesity effects of lactic acid bacteria-fermented Dioscoreae Rhizoma powder (LDR) in Sprague-Dawley rats with high-fat diet (HFD)-induced obesity. Rats were divided into 5 groups: normal diet group, control (high fat diet-vehicle) group, 0.4 g/kg LDR (high fat diet + 0.4 g/kg lactic acid bacteria-fermented Dioscoreae Rhizoma powder) group, 1 g/kg LDR (high fat diet + lactic acid bacteria-fermented Dioscoreae Rhizoma powder) group, 2.5g/kg LDR (high fat diet + lactic acid bacteria-fermented Dioscoreae Rhizoma powder) group. Our results indicate that LDR administration has effects on decreasing of body weight, fat weight, blood parameters and adipocyte size in the obesity animals. In addition, verified that fat degeneration and ballooning degeneration were alleviated in the experimental group fed on a high fat diet combined with LDR groups. These results indicate that lactic acid bacteria-fermented Dioscoreae Rhizoma powder may reduce elevating body weight and lipid accumulation in rat fed a high fat diet, suggesting its usefulness as a functional food for reducing body fat and obesity.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.199-206
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• 2008

Four hundred and thirteen oxytetracycline-resistant bacteria were recovered from six freshwater giant prawn farms with a history of oxytetracycline use. Most oxytetracycline-resistant isolates were Gram-negative bacteria. Six groups of oxytetracycline-resistant bacteria were classified using cluster analysis based on a comparison of levels of oxytetracycline resistance. Complex fingerprint patterns were obtained for 71 isolates studied. In general, the band patterns of isolates from different ponds were very similar, and the data indicated that the isolates were closely related. The exploration for cross-resistance found that most of the 71 oxytetracycline-resistant isolates were also resistant to tetracycline and chlortetracycline, but had a relatively low resistance to doxycycline. Many isolates showed higher chlortetracycline resistance than oxytetracycline resistance. Additionally, the oxytetracycline-resistant isolates were examined for the presence of tetracycline resistance (tet) genes. Fifty percent of the isolates carried one of the 14 known tet genes examined. The most common determinants were TetA and TetD. However, TetB, TetC, TetE, TetK, TetL, and TetM were also found with various frequencies.

• Korean Journal of Agricultural Science
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• v.16 no.2
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• pp.152-162
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• 1989

Oligotrophic bacteria studied in the present report were isolated on a 100-fold dilution of the nutrient broth(NB) medium and were able to grow on a 10,000-fold dilution of the NB medium. Oligotrophbic bacteria were shown to exist abundantly in all layers of a rendzina forest soil through the year. Two-hundred three oligotrophic bacteria were isolated from forest soil at different layers(L.F.H and A layers), and their morphological and physiological characteristics were examined. They were divided into 4 groups on their cell shape: (1) regular rods(Group I. 73 isolates), (2) curved/spiral rods (Group II, 29 isolates), (3) irregular rods (Group III, 56 isolateds), (4) append aged organisms (Group IV, 45 isolates), A high propoltion(95%)of the isolated oligotrophs were Gram-negative. all the isolated were aerobic, nonspore-formers. Forty isolates utilized fenolic acid such as ferulic acid or p-coumaric acid. sixty-for isolateds utilized C-1 compounds such as methanol or formic acid.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.684-689
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• 2005

In order to evaluate the in vitro synergic effect of Mahwangyounpae-tang which was a traditional poly-herbal formula has been used in the treatment of respiratory diseases in oriental medicine, and quinolone antibiotics, ciprofloxacin (CPFX), the minimal inhibitory concentration (MIC), $MIC_{50}$ and MIC90 of single use of quinolones and concomitant treatment with Mahwangyounpae-tang against 5 strains of aerobic gram negative bacteria, Escherichia coli, Klebsiella peumoniae, Hemophilus influenzae, Citrobacter freundii and Pseudomonas aeruginosae. The obtained results were as follows : In the case of aerobic gram negative bacteria, the MIC, $MIC_{50}$ and $MIC_{90}$ against Klebsiella peumoniae and Pseudomonas aeruginosae was significantly decreased in concomitant treated groups with Mahwangyounpae-tang compared to those of single treated groups of CPFX, respectively. However, no significant changes were demonstrated against Echerichia coli, Hemophilus influenzae and Citrobacter freundii. According to these results, it is considered as the in vitro antibacterial activity of CPFX was dramatically increased by concomitant use of Mahwangyounpae-tang against some strains of aerobic gram negative bacteria and the increase and selectivity of antibacterial activities against strains were chosen by the selectivity of Mahwangyounpae-tang not CPFX activity.

• Ocean and Polar Research
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• v.25 no.1
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• pp.21-30
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• 2003

Seasonal fluctuations of physico-chemical and biological aspects of the environment were studied in Vladivostok harbour (Golden Horn Bay, the East Sea/Sea of Japan). The benthic community structure was described with a focus on size-spectra (bacteria, meio- and macrofauna) related with the chemical environment and chemical fluxes in sediment and to reveal their possible ecological role in the process of bioremediation of the environment. Samples from two sites with different concentrations of heavy metals (Fe, Zn, Cu, Pb, Mn, Cr, Ni Cd, Co) and petroleum hydrocarbon were assessed by a number of methods. These included plate counts of culturable bacteria, observation through a scanning electron (SEM) and transmission electron microscope (TEM). These approaches were complemented with microscopic assessments of the diversity of the benthic community. The specific communities had a limited number of species, tolerant to abnormally high levels of toxic compounds. The dominant species were presented by several sho.1-lived small polychaetes (Capitella capitata) and nematodes (Oncholaimium ramosum). The highest population density was recorded in microbenthos, in various diatoms, various physiological groups of bacteria which participate in biomineralization: marine heterotrophic bacteria, which oxidized oil, black oil in addition to groups resistant to heavy metals. They have the entire set of mechanisms for neutralizing the negative effect of those compounds, forming the detrital food web and biogeochemical circulation of material in sediments, which results in the biological self-recycling of sea basins. Macro- and meiobenthic organisms were more sensitive to a greater extent of $H_2S$ and petroleum hydrocarbons than to metal content, but the within-site rankings were the same as those achieved for microbiological analyses.