• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.3
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• pp.126-131
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• 2002

For the probiotic feed production from residual food waste, aerobic liquid fermentation was conducted by thermophilic bacteria. 11 Strains of bacteria were isolated from several soil sources and residual food waste. Screening was carried by shaking incubator for the separation of thermophilic strain at $55^{\circ}C$. The isolated strains were tested for enzyme activities such as ${\alpha}$-amylase and protease. 6 Bacterial strains were chosen and were adapted by repeated fermentation processes in food waste substrate. The viable cell count of them at final fermentation stages were shown as $3-7{\times}10^9/ml$ in 2L-jar fermenter. Among them B3, B6 showed higher enzyme activity. By the mixed fermentation of B3, B6 and Bacillus stearothermophilus, the highest viable cell count reached to $1.4{\times}10^{10}/ml$ in 8 hours.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.44-51
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• 2013

We prepared culture extracts of 174 Corallococcus and 207 Myxococcus strains isolated in Korea, and compared their antimicrobial activity against Candida albicans, Pseudomonas aeruginosa, and Staphylococcus aureus. The percentage of strains showing antifungal activity was lower in Corallococcus (7.5% [13 of the 174 strains]) than in Myxococcus (51.7% [107 of the 207 strains]). However, the percentage of strains exhibiting antibacterial activity was higher in Corallococcus (12.1% [21 strains]) than in Myxococcus (1% [2 strains]). The culture extracts of 6 Corallococcus strains inhibited both P. aeruginosa and S. aureus and displayed similar high-performance liquid chromatography chromatograms, although the shapes of their fruiting bodies were dissimilar. The rate of production of antibacterial substances was the highest when the strains were cultured in CYS medium for more than 6 days.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.452-457
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• 1999

Algicidal bacteria were isolated from the mud of south coastal sea of Korean peninsula and screened to evaluate algicidal activity on Cochlodinium polykrikoides. The optimum condition for the development of highest algicidal activity was determined, The optimum sodium chloride concentration for algicidal activity of isolated algicidal bacteria was $3\%$. The optimum temperature, pH and culture time for the highest algicidal activity were $30^{\circ}C$, pH 7 and above 24 hr, respectively. The algicidal activity were significantly increased at the stationary phase of the cell growth and continuously increased up to maximum at the death phase, probably due to the release of algicidal substance by cell Iysis. The effect of zinc ion addition on algicidal activity, was observed and indicated that the substance requires zinc for its activity. The candidate for the algicidal substance may be $\alpha$-mannosidase.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.694-697
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• 1993

Soymilk was cultured by various human large intestinal bacteria and lactic acid bacteria; Bifidobacterium longum, Lactobacillus acidophilus, Baeteroides fragilis, Eubacterium limosum, Clostridium perfringens and Escherichia coli. Among them, only B. longum utilized raffinose and stachyose actively which are major oligosaccharides present in soymilk by producing active ${\alpha}-galactosidase$ and produced greatest acid. Number of colony forming unit of B. longum reached $1.5{\times}10^{8}$ after 16 hr culture in soymilk. Also Bifidobacterium longum produced the highest level of ${\alpha}-galactosidase,\;{\beta}-galactosidase\;and\;{\alpha}-galactosidase$, in soymilk during culture.

• Journal of Life Science
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• v.6 no.1
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• pp.56-65
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• 1996

Black tea extractbsupplemented with 10% sucrose was fermented by fungus at 30$\circ$C. A pellicle thick as 7$\sim$8 mm covered entire surface of the medium and the wxtract converted to acidic beverage(abbreviated below as fermented black tea) by 14 days of fermentation. It was a kind of acetic acid fermentation depending on symbiotic microorganisms. During the fermentation strains of yeasts(Saccharomyces cerevisiae and Eeniella sp.)and bacteria(Bacillus subtilis, Kurthia zopfii, Gluconobacter oxydans and Deinicoccus sp.) were isolated from aqueous layer. Contrastly to it, a bacterial strain(Acetobacter aceti) was isolated from thick pellicle. The bacteria grew as a viscouse cluster on solid agar medium differently from usual strains of A. aceti. Fermented black tea had sweet-sour taste and sweet smell.

• Microbiology and Biotechnology Letters
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• v.20 no.3
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• pp.329-334
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• 1992

For the photoproduction of molecular hydrogen by photosynthetic bacteria in outdoor conditions, we constructed automatically controlled semi-continuous culture system. When the amount of hydrogen gas produced can be measured by a gas meter with a pulse generator, the same amount of substrate consumed for hydrogen production could be supplied by micro pump related with timers. Using the apparatus, we examined hydrogen production with immobilized cells of Rhodopseudomonas sPhaeroides B6 in outdoor conditions. In spite of severe fluctuation of weather and illumination, the culture was maintained under good control with regard to hydrogen productivity. It was possible to automate the semi-continuous outdoor culture of photosynthetic bacteria for hydrogen production.

• 한국수산학회:학술대회논문집
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• 2005.05a
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• pp.131-132
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• 2005

• Tuberculosis and Respiratory Diseases
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• v.42 no.1
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• pp.67-75
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• 1995

Background: Although we gain new knowledge, the problem of pneumonia will not be eliminated. We should understand who is at risk, why these people develop this problem, what causes the pneumonia, and how to manage and prevent respiratory infection. To clarify the alterations of the etiologies of bacterial pneumonia we analysed the recent causative organisms and evaluated the therapeutic implications. Methods: A retrospective four-year study of bacterial pneumonia was conducted in Soon Chun Hyang University Hospital. 190 episodes of bacterial pneumonia was investigated. Results: 1) The causative organisms were isolated in 173 cases on the sputum culture: 154 cases (89%) were gram negative bacilli and 19 cases(11%) were gram positive cocci. The major organisms were Pseudomonas species 49 cases(28%), Klebsiella pneumoniae 29 cases(17%), Enterobacter species 25 cases(14%), and Acinetobacter species 20 cases(12%) in decreasing order. Pseudomonas species(13 cases, 34%) were frequently found in nosocomial pneumonia. 2) The causative organisms were isolated in 16 cases on the blood culture: 7 cases(43%) were gram negative bacilli and 9 cases(57%) were gram positive cocci. The major organisms were Staphylococcus aureus(6 cases, 38%), Pseudomonas species(3 cases, 19%) in decreasing order. 3) In the susceptibility test of causative organisms to antimicrobial drugs, Pseudomonas was susceptible to amikacin, ciprofloxacin, aztreonam, ceftazidime(more than 50%) and resistant to piperacillin, gentamicin, carbenicillin(more than 60%). Klebsiella was susceptible to chloramphenicol, gentamicin, cefotetan(more than 70%) and resistant to carbenicillin, ampicillin(more than 70%). Staphylococcus was susceptible to methicillin(64%), and Streptococcus pneumoniae was susceptible to oxacillin(94%). 4) The response rate after antibiotics therapy was 81% and the mortality rate was 19%. Conclusion: As considering the changes of causative organisms and antibiotic resistance, it behooves us to exercise caution in dispending antibiotics in order to maximize their continued efficacy and to do appropiate antibiotics therapy based on cultures and susceptibility test.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.270-274
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• 1988

Samples used for the enrichment culture were collected from the sea water of suspected chronic petroleum contamination in the vicinity of Pusan, Chungmu and Ulsan ports, Korea. Alkaline Iysis and agarose gel electrophoresis techniques were employed to screen these isolates for the presence of plasmid DNA. There were n little differences in the percentage of isolates containing plasmids between sampling sites of unpolluted sen water (22％) and polluted son water (25％). Bacterial isolates taken from the Bunker-C oil enriched culture showed significantly more plasmid incidence (29％). About two thirds of strains grown on a variety of hydrocarbons were Gram negative strains of which 33％ contained one or more plasmids. Multiple plasmids were observed in 23％ of the plasmid-carrying strains. Forty one percent of the plasmids detected were estimated to have a mass of 20 kb or more.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.1
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• pp.9-17
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• 2008

The presence of thiosulfate oxidizing bacteria was examined in rhizosphere soils of 19 economically important plant species belonging to 10 different families. The results showed that the thiosulfate oxidizing bacteria were present in all the tested rhizosphere soils, and the total 32 thiosulfate oxidizing bacteria were recovered. Furthermore, the biochemical characterization revealed that 56% and 44% of the isolates belonged to the obligate chemolithoautotrophs and facultative heterotrophs, respectively. The isolates ATSR15P utilized 19.17 mM of thiosulfate and accumulated 11.65 mM of sulfate in the medium. Concurrently, the decrease in pH of the medium was observed. This study comprehensively demonstrates that the active sulfur oxidation is a ubiquitous phenomenon in the rhizosphere of crop plants in Korea.