• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.431-437
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• 2005

In this study, the profiles of the bacterial regrowth of indigenous bacteria in tap water and Pseudomonas fluorescence P17 were investigated for cases when carbon (glucose), and/or nitrogen ($NO_3^-$-N), and/or phosphorus ($PO_4^{3-}$-P) were added below sufficient nutrient concentration (SNC) and when carbon sources (glucose and acetate) and nitrogen sources ($NH_4^+$-N and $NO_3^-$-N) were added together. The bacterial regrowth was decreased with limitation of nutrients, and were lowered relatively in the sample, which plural nutrients were limited. In addition, phosphate might be the effective nutrient to control the bacterial regrowth in drinking water because the bacterial regrowth was significantly decreased by the limitation of phosphate. In contrast, the bacterial regrowth was retarded with increasing the concentration of $NO_3^-$-N. For simultaneously adding carbon(glucose or acetate) and nitrogen sources ($NH_4^+$-N and $NO_3^-$-N), the regrowth counts appeared highly in the condition, for both glucose and acetate. And, the regrowth was increased with increasing $NH_4^+$-N concentration as a nitrogen source.

• Journal of the Korean Academy of Pediatric Dentistry
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• v.27 no.1
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• pp.90-97
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• 2000

There are various kinds of factors associated with the formation of dental plaque in oral cavity such as nutrient molecules and chemical agents. The factors influencing the formation of insoluble glucan by Streptococcus sobrinus and its replication were examined on orthodontic wires. The results were as follows: 1. Insoluble glucan was well produced in the media initially adjusted at pH 7.0 than pH 5.5 or pH 8.5 like bacterial replication. 2. The synthesis of insoluble glucan and bacterial replication were significantly increased in the media containing 2.5% yeast extract. The formation of insoluble glucan was inhibited by 10 folds in the media containing 20% of sucrose than 1.25%, but the replication of bacteria was increased by 20 folds. 3. Insoluble glucan was significantly formed at a concentration of 1.0mM of calcium chloride, 40mM of potassium chloride, 0.1mM of magnesium chloride, while the replication of bacteria was little influenced by them regardless their concentration. 4. The formation of insoluble glucan and bacterial replication were significant in the media containing 10mM of sodium bicarbonate, but both were completely inhibited at 100mM or above. The production of insoluble glucan and the bacterial replication were largely decreased at 10mM of Tris while insoluble glucan was formed in abundance at 100mM of Tris. 5. The synthesis of insoluble glucan and the bacterial replication were inhibited at 10mM or above of sodium phosphate and potassium phosphate.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.101-108
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• 1982

The effects of ginseng extract and ginseng saponin on the growth of bacterial cells were variable depending upon the species of bacterium and concentrations of saponin. Serratia marcescens and Aerobocter aerosenes showed the maximum growth in the basal medium pius 0.1% of ginseng extract, but did the suppressed growth in the medium plus above 1 % of ainseng extract. Stophylococcus aureus and Escherichia coli showed the maximum growth in the basal medium plus 5% of ginseng extract. The slightly accelerated growth was shown with Micrococus flavus and Aerobacter aerogenes cultivated in the basal medium plus 0.002% of ginseng saponin, but the remarkably supressed growth was done in the medium plus above 0.02% of ginseng saponin. Ginseng saponin functioned a physiologically suppressing factor of growth to genus Serratia, but no antimicrobial activity was found against Erwinia aroideae and Sarcina marginata. The substance causing the antimicrobial activity from ginseng saponin was proven to be a ginsenoside Rg$_1$.

• Korean journal of food and cookery science
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• v.13 no.3
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• pp.330-337
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• 1997

The sensitivity of various pathogenic bacteria (Aeromonas hydrophila, Estherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus 196E, Salmonella typhimurium and Vibrio parahaemolyticus) to the spices, allspice, clove, oregano, and thyme, was tested. Tryptic soy broth (TSB) containing 0∼2% (w/v) of spices was inoculated with 10sup 5/∼10$\^$6/ cells/$m\ell$ of each bacterium and incubated at 35$^{\circ}C$ for 24 hr. The growth of pathogenic bacteria was inhibited with increasing concentrations of spices in the culture broth. At 2％ spice concentration, Gram positive bacteria were more sensitive than Gram negative bacteria with the exception of V. parahaemolyticus. Clove had the highest antibacterial activity, followed by allspice and oregano. At the concentration of 0.3%, clove inhibited the growth of all strains tested. Kanagawa-positive strain of V. parahaemolyticus displayed the highest sensitivity to clove and allspice. Thyme was the least effective for growth inhibition, while 1％ clove killed all pathogens tested.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.2
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• pp.132-136
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• 1990

This experiment was conducted to study the multiplication and spread of bacterial population in water exuded through the hydathode of infected leaf of Xanthomonas campestris pv. oryzae in resistant and susceptible rice cultivars to bacterial leaf blight. The results obtained are summarized as follows. The bacterial multiplication in resistant cultivars was almost constant from three days to twelve days after inoculation with population of 10$^3$-10$^4$cfu/$\textrm{cm}^2$, but the multiplication was increased as days after inoculation extended in susceptible cultivars. The speed of bacterial multiplication and the number of bacteria spread above and below the inoculated position were closely related with the resistance of rice cultivars to bacterial leaf blight. The bacterial multiplication and spread were observed throughout the all growing stages including seedling, maximum tillering and flag leaf stages. The bacterial populations in water exuded through the hydathode were dependent on the multiplication and spread, and the populations were also closely related with the resistance of rice cultivars.

• Food Science and Preservation
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• v.5 no.3
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• pp.286-291
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• 1998

The sensitivity of various pathogenic bacteria(Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus 196E, Salmonella typhimurium) to the water extract of green tea was tested. Tryptic soy broth was inoculated with 10$\^$5/CPU/ml of pathogenic bacteria and incubated at 35$^{\circ}C$ for 30 hours. The extract was added at a final concentration of 0-2%(w/v) into culture broth at the mid or late exponential phase of bacteria. The growth of pathogenic bacteria was inhibited with increasing concentrations of the extract in culture broth and the late exponential phase cells were more resistant than the mid exponential phase cells. Cram positive bacteria(L. monocytogenes and S. aureus 196E) were more sensitive than Cram negative bacteria(E. coli O157:H7 and S. typhimurium). S. aureus had the highest sensitivity, followed by L monocytogenes, E. coli O157:H7. S. typhimurium was the most resistant to the water extract of green tea.

• Applied Biological Chemistry
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• v.22 no.2
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• pp.101-108
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• 1979

The viscosity of mucilage of Abelmoschus Manihot, Medic root decreased by the influence of various mechanical, physical and chemical conditions. It was experimented by viscosity decrease of mucilage connected with hydrogen ion concentration, bacterial multiplication, disinfection with 70% ethanol, some antibiotics, such as streptomycin, penicillin, ganamycin and chloramphenicol and mucilage derived from autoclaved Abelmoschus Manihot, Medic root. The results obtained were as follows: 1. It was clear that the viscosify of mucilage decreased notably under the influence of infected bacteria and bacterial multiplication. 2. By the inoculation of Bacillus subtilis ATCC 6633 and Escherichia coli ML 1410 to the mucilage the viscosify decrease fast but the viscosity of mucilage derived from autoclaved, Abelmoschus Manihot, Medic root. 3. The small quantity of reducing sugar in the mucilage was detected. 4. Hydrogan ion concentration in the mucilage remained $6.5{\sim}8.0$ in spite of the viscosity decrease.

• The Microorganisms and Industry
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• v.15 no.1
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• pp.16-17
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• 1989

우리들의 주변환경에는 어느 곳에나 여러가지 미생물이 무수하게 존재하며 이들 미생물들은 그 환경조건이 이들의 서식에 적합하기만 하면 증식한다. 이들 미생물들 가운데서 섬유재료에 영향을 주는 것으로는 주로 일부의 세균과 곰팡이(사상균)류가 있다. 섬유에 영향을 주는 작용을 대별하면 1) 섬유재료의 파괴(부패작용), 2) 섬유제품의 착색오염, 3) 섬유중에서 증식되는 병원균에 의한 질병 유발, 4) 악취발생 등이라고 할 수 있다. 우리의 환경은 각종 미생물에 오염되기 쉬운 상태에 있으므로, 섬유재료의 파괴를 방지하고 될 수 있는대로 건강하고 쾌적한 의생활을 영위하려는 목적으로, 세균과 곰팡이의 증식을 억제 또는 저지 할 수 있는 항균제를 섬유제품에 처리하게 되었다.

• Food Industry
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• s.3
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• pp.22-24
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• 1971

우리는 일상생활속에서 각종세균과 공존하고 있는 것이다. 더욱이 이들 세균들은 고온에서 증식이 왕성 함으로 다습하고 온도가 높은 하절기에는 우리들의 생활주변에서 각종질병이라는 형태로 우리들의 건강관리에 위협을 주고 있는 것이다.

• KOREAN POULTRY JOURNAL
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• v.15 s.164
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• pp.126-131
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• 1983

식중독은 단체급식소에서 주로 발생하여 많은 사람들에게 피해를 준다. 이를 예방하기 위해서는 식품을 저온 보존하여 세균증식을 억제하고, 식품취급을 위생적으로 하여 오염 경로를 차단하는 것이 중요하다.