• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2002.11a
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• pp.148-148
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• 2002

수분부족 및 hyperoxaluria가 유도된 랫드에서 enrofloxacin 투여로 인한 신장손상을 알아보기 위하여 본 실험을 실시하였다. 랫드는 모두 4 그룹으로 나누어 실험에 공하였다. 실험은 72시간 탈수를 유발시킨 랫드 (Group 1), 3％ sodium oxalate를 음수로 7 일간 급여해서 hyperoxaluria 상태를 유발시킨 랫드 (Group 2, 3) 그리고 sodium oxalate 30mg/Kg을 1회 복강내 투여로 급성 hyperoxaluria 상태를 유발시킨 랫드(Group 4)에 각각 enrofloxacin을 용량별 (0mg/Kg, 50mg/Kg, 500mg/Kg)로 1일 혹은 7일 동안 투여한 후 임상 및 병리조직학적 소견을 추구하였던 바 다음과 같은 결과를 얻었다. 수분부족이나 hyperoxaluria 가 유도된 상태의 전 그룹에서 enrofloxacin 투여용량이 증가할수록 식욕감소, 음수량 감소, 행동둔화 등의 임상증상과 사구체의 손상, 신장피질내 충혈, 세뇨관의 변성, 공포화, 괴사 등의 변화가 현저히 진행되는 것을 알 수 있었고, Group 2, 3, 4 실험군의 소변을 원심분리하여 침전된 뇨침사를 현미경으로 검사한 결과 모든 군에서 calcium oxalate crystal이 검출되었고 일부는 magnesium ammonium phosphate crystal이 검출되었다. 이상의 결과를 종합해 볼 때, 탈수상태나 혈중 oxalate함량이 높은 랫드에서 enrofloxacin의 투여는 신장에 손상을 주어 결석을 형성할 수도 있는 것으로 사료되며 이러한 개체에서 enrofloxacin의 사용상 주의가 요구된다.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.1-7
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• 2015

Global population is expected to reach nine billion in 2050 and the total demand for food is expected to increase approximately by 60 percent by 2050 as compared to 2005. Therefore, it is important to increase crop production in order to meet the global demand for food. Slow release fertilizers have been developed and designed in order to improve the efficiency of fertilizers. Mineral-based slow release fertilizers are useful because the minerals have a crystalline structure and are environmentally friendly in a soil. This review focuses on slow release fertilizers based on montmorillonite, zeolite, and layered double hydroxide phases as a host for nutrients, especially N. Urea was successfully stabilized in the interlayer space of montmorillonite by the formation of urea-Mg or Ca complex, $[(Urea)_6Mg\;or\;Ca]^{2+}$ protecting its rapid degradation in soils. Naturally occurring zeolites occluded with ammonium nitrate and potassium nitrate by molten salt treatment could be used as slow release fertilizer because the occlusion process increased the capacity of zeolites to store nutrients in addition to exchangeable cations. Additionally, surface-modified zeolites could also be used as slow release fertilizer because the modified surface showed high affinity for anionic nutrients such as nitrate and phosphate. Moreover, there were attempts to develop and use synthetic layered double hydroxide as a carrier of nitrate because it has positively charged layers which electrostatically bond nitrate anions. Kaolin was also tested by combining with a polymer or through the mechanical-chemical process for slow release of nutrients.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.211-216
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• 2005

The bacteriocin produced by E. faecium MJ-14 was precipitated with $50\%$ saturated ammonium sulfate in MRS broth and then the precipitated protein was dissolved in 20 mM sodium phosphate buffer (pH 6.0). The crude bacteriocin was purified by CM-sepharose CL 6B and Sephacry S-100 column chormatograhy. In this case, the purification fold of the bacteriocin was 114, therefore, its activity was 127,293 BU/mg of specific activity. Result from SDS-PAGE of the purified bacteriocin, it was obtained two protein bands of 4.3 kDa and 5.8 kDa having antilisterial activity.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.53.1-53.1
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• 2011

Bioactive glass powders were synthesized by hydrothermal chemical route by the use of ultrasonic energy irradiation. We used sodalime, calcium nitrate tetra hydrate and di ammonium hydrogen phosphate as the precursor material to synthesize $SiO_2$ rich bio-active glass materials. The $SiO_2$ content was varied in the precursor mixture to 60, 52 and 45 mole%. Dense compacts were obtained by microwave sintering at $1,100^{\circ}C$. Mechanical properties were characterized for the fabricated dense bioactive glasses and were found to be comparable with conventional CaO-$SiO_2$-$Na_2O$-$P_2O_5$ bioactive glass. Detailed biocompatibility evaluation of the glass composition was investigated by in-vitro culture of MG-63 cell and mesenchyme stem cell. Cell adhesion behavior was investigated for both of the cell by one cell morphology for 30, 60 and 90 minutes. Cell proliferation behavior was investigated by culturing both of the cells for 1, 3 and 7 days and was found to be excellent. Both SEM and confocal laser scanning microscopy were used for the investigation. Western blot analysis was performed to evaluate the bimolecular level interaction and extent and rate of specific protein expression. The ability to form biological apatite in physiological condition was observed with simulated body fluid (SBF). In-vivo bone formation behavior was investigated after implanting the materials inside rabbit femur for 1 and 3 month. The bone formation behavior was excellent in all the bioglass compositions, specially the composition with 60% $SiO_2$ content showed most promising trend.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.451-455
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• 1992

In the medium containing 7% rice powder, 0.15% $NH_4NO_3$ and 0.1% $MnSO_4$ with initial pH 6.0, the red pigment production by Monascus anka albidus was observed. The mycelium were cultured at $30^{\circ}C$ for 5 days with reciprocal shaking (130 rpm). As a carbon source, glutinous rice gave the highest production of pigment. Ammonium nitrate and $KH_2PO_4$ as a nitrogen source and phosphate source, respectively, stimulated best the production of the red pigment. The optimum C:N ratio was found to be 18:1. The production of the pigment by the strain was 2.6 mg/ml in a flask, but 1.8 mg/ml in 5l fermentor, respectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.49-56
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• 2010

In the pyroprocessing of spent nuclear fuels, LiCl-KCl waste salt containing radioactive rare earth chlorides are generated. The radioactive rare earth oxides are recovered by co-oxidative precipitation of rare earth elements. The powder phase of rare eath oxide waste must be immobilized to produce a monolithic wasteform suitable for storage and ultimate disposal. The immobilization of these waste developed in this study involves a solid state sintering of the waste with host borosilicate glass and zinc titanate based ceramic matrix(ZIT). And the rare-earth monazite which synthesised by reaction of ammonium di-hydrogen phosphate with the rare earth oxides waste, were immobilzed with the borosilicate glass. It is shown that the developed ZIT ceramic wasteform is highly resistant the leaching process, high density and thermal conductivity.

• Korean Journal of Microbiology
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• v.31 no.4
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• pp.261-266
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• 1993

A new methyltrophic bacterium which utilizes methanol as a sole source of carbon and energy was isolated from soil. It was Gram-negative, nonmotile, nonspore-forming rod, and strictly aerobic bacterium. Catalase and oxidase activities were present. Nitrate was reduced to nitrite. Vitamins and other growth factors were not required. Generation time was 1.6 hr under the optimal condition. The isolate assimilated methanol via the ribulose mono-phosphate pathway (Enter-Doudoroff varient) and did not have .alpha.-ketoglutarate dehydrogenase. It assimilated ammonia through glutamate dehydrogenase. The guanine plus cytosine content of the DNA was 61.0 mol%. The celular fatty acid composition was primarily straight-chain saturated $C^{16 : 0}$ acids (palmitic acids) and unsaturated $C_{16 :1}$ acid (palmitoleic acids), and the isolate also contained two unidentified $C_{17}$ branched fatty acids. The major ubiquinone was Q-8, and Q-6 and Q-7 were present as minor components. Phosphatidylethanolamine and phosphatidylglycerol were predominantly present, and diphosphatidyglycerol was also detected. Based on the physiological and biochemical properties, the isolate was assigned to a novel species of the genus Methylobacillus, Methylobacillus methanolovorus sp. nov.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.145-154
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• 1982

To maximize the production of glucose oxidase by Aspergillus niger KUF-04 isolated from a soil, the cultivation conditions and nutrient sources for the enzyme production were studied. The results obtained were as fellows: 1. The optimum temperature, pH of the medium, and cultivation time for the enzyme formation were found to be 28-34$^{\circ}C$, 7.0-8.0 and 40 hours, respectively. 2. The best carbon source was proved to be glucose and its most effective concentration was 15 percent. 3. Ammonium sulfate was the best nitrogen source as compared with the other inorganic and organic nitrogen sources tested. Its optimum concentration for the glucose oxidase production was 0.02 percent. 4. As mineral sources, 0.05% of Mag cesium sulfate 7-hydrate and 0.02% of Potassium phosphate, monobasic seemed to be necessary to further increase the level of the enzyme production.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.1
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• pp.65-75
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• 2012

To study the difference in growth characteristics between intertidal and subtidal eelgrass Zostera marina populations, environmental factors and changes in tissue carbon (C) and nitrogen (N) contents in eelgrass from the lower intertidal and upper subtidal zones were surveyed monthly in the Seomjin Estuary from May 2003 to December 2004. Water temperatures, water column nutrient concentrations, sediment pore water, and ammonium and phosphate concentrations showed no significant differences between intertidal and subtidal zones. Sediment pore water nitrate+nitrite concentrations were slightly higher in the intertidal zone than in the subtidal zone. Average monthly exposure times in the intertidal and subtidal zones were $42.4{\pm}5.8h\;month^{-1}$ and $15.3{\pm}3.5h\;month^{-1}$, respectively. Eelgrass leaf N content decreased from March to August and increased from September to February in the subtidal zone, whereas these trends were not observed in the intertidal zone. Eelgrass rhizome C content increased from April to September and decreased from October to March in the subtidal zone, whereas those tendencies were not recorded in the intertidal zone. Eelgrass rhizome C:N ratios showed a strong reverse trend to leaf C:N ratios in the subtidal zone, but these tendencies were not observed in the intertidal zone. The effects of exposure appeared to cause no seasonal trend in eelgrass tissue C and N content or C:N ratios in the intertidal zone in the Seomjin Estuary.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.224-229
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• 2004

Several microorganisms (esterase-producing group) were isolated by the solid selective media containing-naphtylacetate. Among them, strain 366M-9 having a high activity of cephalosporin-C deacetylase (CAH; EC 3.1.1.41) was selected. The strain 366M-9 was identified as Bacillus sphaericus on the basis of morphological, physiological, and biochemical characteristics. The production of CAH reached at maximum value after 32 hrs, when cultivated in the optimal medium containing dextrin 2.5%, peptone 2.5%, sodium chloride 0.5%, dipotassium phosphate 0.25%, ferrous sulfate 0.02%, and 7-ACA 0.1% at $30^{\circ}C$ with initial pH 6.0. The CAH was purified by 3 steps with ammonium sulfate precipitation, adsorption chromatography on hydroxyapatite column, and Sephadex G-200 gel chromatography. The final enzyme preparation was homogeneous as judged by the analysis of SDS-PAGE and HPLC. Optimum temperature and pH for CAH activity were $50{\circ}C$ and around 7.0, respectively. And the enzyme was stable at pH 6.0～8.0, up to $50^{\circ}C$. The Michaelis-Menten constants ($K_{m}$ ), $V_{max}$ were 0.87 mM and 1.22 unit/ml, respectively.