• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.834-841
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• 1997

A lactic acid bacteria which showed antimicrobial activity was isolated from dairy products and identified as Lactobacillus sp. according to the morphological, physiological and biochemical properties, which was named Lactobacillus sp. SH 7311. The bacteriocin of Lactobacillus sp. GM 7311 showed a broad range of inhibitory spectrum against some gram positive and negative bacteria. Especially, Proteus mirabilis was highly sensitive to bacteriocin and used as indicator strain for further investigation. The optimal condition for the production of bacteriocin was showed on MRS broth at $37^{\circ}C$ and pM 6.0. Bacteriocin production of this strain cultured under optimal condition was increased late logarithmic phase to early stationary phase. This bacteriocin was fully active at the pH range $2.0\~5.0$, also was stable at $100^{\circ}C$ for 60 min. at pH 5.0, But about $40\%$ of bacteriocin activity was diminished by the treatment of acetone, ethanol, iso-butanol and ethyl ether during 2 hours at $4^{\circ}C$.

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.234-238
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• 2001

For the comparison of fermentation pattern of leek kimci with chinese cabbage kimchi, the changes of total viable cell number, Leuconostoc sp. bacteria, Lactobacillus sp. bacteria, pH and total sugar content of twotypes kimchies were investigated during fermentation at $20^{\circ}C$ and $10^{\circ}C$. In chinese cabbage kimchi at $20^{\circ}C$ fermentaion, the numbers of total viable cell, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria reachedthe maximum level on 2nd day and reduced slowly. But in leek kimchi, the maximum numbers of total via-ble cells, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria were obtained after 3 days fermentation,and the cell number of Lactobacillus sp. maintained at the maximum level oyer 15 days. At $10^{\circ}C$ fer-mentation, in both kimchies, the viable cell number of lactic acid bacteria more slowly increased anddecreased than at $20^{\circ}C$. The pH of chinese cabbage kimchi was 4.2 on 3rd day (optimal ripening phase) andmere decreased to 3.5 after 5 days, but in leek kimci the pH 4.2 could be reached after 10 days at $20^{\circ}C$. At $10^{\circ}C$, the optimal ripening pH 4.2 of chinese cabbage kimchi was reached after 6 days, but in leek kimchieven though after 24 days, the pH was maintained oyer 4.3. The total sugar contents of chinese cabbage him-chi and leek kimci were decreased continuously during fermentation. From these results, we know that thefermentation of leek kimchi proceed more slowly than chinese cabbage kimchi by the retardation of lacticacid bacteria growing in leek kimchi.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.245-247
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• 2003

축산폐수에서 분리된 세균 S. sp1(S. capitis)와 S. sp2(3. xylosus)를 이용한 축산폐수 중 질소화합물 분해정도를 파악한 결과 1) 증식에 알맞은 조건은 LB broth, $27^{\circ}C$, pH7로 나타났다. 2) S. sp1은 배양 7일 초기 농도의 90.3%, 7일째 32.9%로 감소되어 14일까지 다소 증가하면서 유지되었다. 3) S. sp1과 S. sp2를 혼합배양한 결과 S. sp1과 S. sp2 단독배양보다 분해 효율이 높고 기간도 2일정도 단축되었다.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.419-426
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• 2006

A thermophilic microorganism, strain JE 375, which produces a thermostable protease, was isolated from soil and compost in Korea. This gram-positive, rod-shaped, catalase positive, motility positive, and hemolysis ${\beta}$ containing organism was implicated in glucose fermentation, mannitol fermentation, xylose oxidation, aerobic activity and spore formation. The color of the colony was yellowish white. The temperature range for growth at pH 6.5 was between 55 and $70^{\circ}C$, with an optimum growth temperature of $65^{\circ}C$. This result confirmed the strain JE 375 as a thermophilic microorganism. The enzyme was produced aerobically at $65^{\circ}C$ during 20 hr in a medium (pH 6.5) containing 1% trypton. 1% maltose, 0.5% yeast extract and 1% NaCl. The 16S rDNA of strain JE 375 had 97.6% sequence similarity with the 16S rDNA of Bacillus caldoxyloyticus. On the basis of biochemical and physiological properties and phylogenetic analysis, we named the isolated strain as Bacillus sp. JE 375. The thermostable protease from Bacillus sp. JE 375 had been partially purified and characterized. The molecular weight of the enzyme was deduced from SDS-PAGE and gel chromatography as 55 kDa and its optimal temperature was $60^{\circ}C$. The enzyme showed its highest activity at pH 7.5 and was stable from pH 7.0 to 8.0.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.484-489
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• 1997

The characteristics of growth and esterase activity of bacterial strains isolated from acid hydrolysed soybean protein were examined. All the isolated strains having decomposition activity of p-hydroxybenzoic acid butyl ester and esterase producing activity were identified as Bacillus sp. by morphological and biochemical methods. The specific growth rates, esterase activities and p-hydroxybenzoic acid butyl ester decomposition activities of isolated strains were $0.844{\sim}1.213\;h^{-1}$, $21{\sim}222\;mU/ml$ and $5.4{\sim}8.1\;mU/ml$, respectively. In the fermentation of Bacillus sp. KB8 strain which had the highest esterase producing activity, growth, extracellular excretion and intracellular synthesis of esterase were inhibited by adding NaCl in the culture broth. Esterase producing activity gradually increased after late exponential growth phase, until maximum value of 420 mU/ml reached after 64 hours culture period. Esterase of Bacillus sp. KB8 strain was stable up to $50^{\circ}C$ for 30 minutes, but was inactivated by heating for 30 minutes at $70^{\circ}C$. The enzyme activity exponentially decreased during the incubation time at the temperatures of $60^{\circ}C$ and $65^{\circ}C$.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.559-562
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• 2000

A halotolerant and extracellular pretense producing yeast was isolated from traditional Meju and identified as a strain of Hansenular sp. S-9 by investigation of its microbiological characteristics. The optimum pH, temperature and NaCl concentration for growth of Hansenular sp. S-9 were pH 7.5, $30^{\circ}C$ and 0.5M, respectively. The protease production from Hansenular sp. S-9 was maximized when it was grown on BD medium containing 1.0% beef extract, 1.0% glucose and 0.5M NaCl for 72 h at $30^{\circ}C$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1211-1214
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• 2003

The film is prepared by electron cyclotron resonance chemical vapor deposition (ECRCVD) employing CH$_4$ and H$_2$ gases. It is deposited by the control of microwave plasma power, gas flow ratio, deposition pressure, and In-situ thermal treatment temperature. The structure of a-C:H (hydrogenated amorphous carbon) thin film is analysed by FT-IR spectroscopy. The fraction sp$^3$ versus sp$^2$ bonding is very important to clear up the surface and interrace of a-C:H film properties such as nano-scale friction behavior. The sp$^3$ versus sp$^2$ bonding of a-C:H thin film is dependent on the deposition conditions, therefore. nano-scale friction behavior is dependent on the deposition conditions.

• Korean Journal of Organic Agriculture
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• v.12 no.2
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• pp.183-196
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• 2004

This study was carried out to screen and select the effects of antifungal bacterial strains which inhibit the growth of plant pathogen, Fusarium oxysporum(fusarium wilt) occurred in carnation plants in greenhouse. We isolated an effective bacterial strains and investigated into the antifungal activity of the antagonistic microorganism and it's identification. Twenty bacterial strains which strongly inhibited Fusarium oxysporum were isolated from roots of carnation plants and the soil in greenhouse, and the best antifungal bacteria designated as C121, was finally selected. Antagonistic bacterial strain, C121 was identified to be the genus Bacillus sp. based on the morphological, biochemical and cultural characterizations. The Bacillus sp. C121 showed 58.1% of antifungal activity against the growth of Fusarium oxysporum. By the bacterialization of the cultural broth and the heat bacterialization culture filtrate of it, Bacillus sp. C121 was shown 92.1% and 21.0% of antifungal activity, respectively.

• Journal of Microbiology
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• v.39 no.4
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• pp.326-330
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• 2001

Mycobacterium sp. C2-3 was isolated from petroleum contaminated soil around an oil reservoir and identified by analysis of its 16S rRNA gene sequence, Strain C2-3 was able to use fluorene, phenan-threne, fluorathene and pyene as sole sources of carbon and energy, yet unable to geagrade naph-thalene, The strain was also able to use n-alkanes, such as hexadecane and heptadecane, and phenanthrene and pyrene, in particular, were degraded rapidly,. The phylogenetic data suggested that the isolate C2-3 is a thermosensitive, fast-growin strain of Mycobacterium sp.

• Animal cells and systems
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• v.10 no.2
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• pp.109-114
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• 2006

A study on marine sponges was conducted with the materials collected by SCUBA diving in Hongdo and Gageodo Islands, Korea from September 2004 to July 2005. Clathria (Clathria) hongdoensis n. sp. and Clathria (Clathria) sohuksanensis n. sp. turned out to be new to the science. Clathria (Clathria) hongdoensis n. sp. closely seems to C. (C.) acanthstyli Hoshino (1981), based on their spicules type. However, they differ in the size of spicules and growth form. Clathria (Clathria) sohuksanensis n. sp. is similar to C. (C.) bicalthrata Hooper (1996), except for lacking small toxas.