• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.4
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• pp.297-302
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• 2004

A chitinase-producing bacterium was isolated from seashore mud around Beobseongpo in Chunmam province through the use of a selective enrichment culture. The best chitinase producing strain was isolated and identified as Serratia marcescens KY from its characteristics. For effective production of chitinase, optimum pH, temperature, and agitation speed were investigated in flask cultures. The optimum pH using Serratia marcescens KY was between pH 6 and 7 and the chitinase produced was 37.9 unit/mL. On the other hand, the optimal pH of the Serratia marcescens ATCC 27117 was 7.5, and the produced amount of chitinase was 35.2 unit/mL. The optimal temperature for chitinase production for Serratia marcescens KY and Serratia marcescens ATCC 27117 was $30^{\circ}$. The cell growth pattern at different temperature was almost identical to the chitinase production. To investigate the optimal shaking speed under optimal culture, speeds were varied in the range of 0∼300 rpm. The maximum production of chitinase was carried at 200 rpm although the cell growth was the highest at 150 rpm. It indicates that oxygen adjustment is required for the maximum chitinase production. Using optimal conditions, batch cultures for comparing Serratia marcescens KY and Serratia marcescens ATCC 27117 were carried out in a 5 L fermentor. The oxygen consumption was increased with the increase of culture. Especially, at 120 h of culture Serratia marcescens KY and Serratia marcescens ATCC 27117 produced 38.3 unit/mL, and 33.5 unit/mL, respectively.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.26-34
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• 1992

The effect of induction temperature on fermentation parameters has been investigated extensively using Escherichia coli M5248[pNKM21], a producer of recombinant human interleukin-2 (rhIL-2). In this recombinant microorganism, the gene expression of rhIL-2 is regulated by the cI857 repressor and $P_L$ promoter system. The recombinant fermentation parameters studied in this work include the cell growth, protein synthesis, cell viability, plasmid stability, $\beta$-lactamase activity, and rhIL-2 productivity. Interrelationships of such fermentation parameters have been analyzed through a quantitative assessment of the experimental data set obtained at eight different culture conditions. While the expression of rhIL-2 gene was repressed at culture temperatures below $34^\circ{C}$ with little effect on other fermentation parameters, under the conditions of rhIL-2 production $>(36~44^\circ{C})$ the cell growth, plasmid stability, and $\beta$-lactamase activity were, as induction temperature was increased, more profoundly reduced. Although the rhIL-2 content in the insoluble protein fraction was maximum at $40^\circ{C}$, total rhIL-2 production in the culture volume was found to be highest at the induction temperature of $36^\circ{C}$. This was in contrast to the previously known optimum induction temperature of the P$_{L}$ promoter system $>(40~42^\circ{C})$.Explanations for such a discrepancy have been proposed based on a product formation kinetics, and their implications have been discussed in detail.l.

• Herbal Formula Science
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• v.21 no.2
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• pp.81-89
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• 2013

Objectives : The purpose of this study is to observe the effect of Coptidis Rhizoma (CCE-extract of C. chinensis Rhizome) in induction of immune protein on mouse macrophages. Methods : To analyze cytokines interleukin(IL)-$1{\alpha}$, IL-3, IL-9, IL-12p40, IL-13, IL-17, Monocyte Chemoattractant Protein(MCP)-1 induced by macrophages, mouse macrophages were incubated with CCE and was measured. Results : IL-$1{\alpha}$ measurement, CCE showed significant inhibition only at concentration level of 200 ${\mu}g/mL$. IL-3, MCP-1 measurement, CCE showed significant inhibition only at concentration level of 100, 200 ${\mu}g/mL$. IL-9 measurement, CCE showed significant inhibition only at concentration level of 50 ${\mu}g/mL$. IL-13 measurement, CCE showed significant inhibition only at concentration level of 50, 100, 200 ${\mu}g/mL$. The IL-12p40, IL-17 levels indicated no changes at 25, 50, 100, 200 ${\mu}g/mL$ on mouse macrophages. Conclusions : CCE did not significantly increased inflammatory cytokines IL-$1{\alpha}$, IL-3, IL-9, IL-12p40, IL-13, IL-17, Monocyte Chemoattractant Protein(MCP)-1 on mouse macrophages. It was verified CCE does not trigger cytokine related hypersensitivity reaction of organism or exacerbation of acute/chronic inflammatory disease.

• Microbiology and Biotechnology Letters
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• v.37 no.1
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• pp.75-79
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• 2009

In this study, we polymerized new materials for soft contact lens using HEMA (2-hydroxyethyl methacrylate) which is the based-monomer of soft contact lens, EGDMA (ethylene glycol dimethacrylate) as cross linkage agent, and the new additives of monoester or di-ester derived from itaconic acid commercially produced by the fermentation of Asp. itaconicus. New polymer materials for soft contact lens were synthesized with the mixture of HEMA and mono- or diester at different ratios and presented to a good water content and oxygen transmissibility (Dk/L) values. In case of polymerization with HEMA and mono-ester (15%), the water content and oxygen transmissibility of contact lens were found to be good values at 57.6% and 28.5 Dk respectively. The mixture of HEMA and mono-ester is more excellent than HEMA/di-ester in the water content and oxygen transmissibility. The toxicity of new contact lens materials were confirmed in the fibroblast L-929 cell line using a agar overlay test and a growth inhibition test with the extract solution of contact lens.

• Journal of Sericultural and Entomological Science
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• v.47 no.2
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• pp.56-61
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• 2005

New mulberry cultivar, Shinsungppong which was resistant to main mulberry disease was bred and resistered as a commercial cultivar. Local adaptability test has been carried out at three places (Suwon, Kongju, and Jinju) for four years since 2001. Leaf quality was tested by silkworm rearing for two silkworm rearing seasons (spring and autumn) at Suwon in 2000. Shinsungppong was recognized to be superior by 7% in productivity to control cultivar, Sangilppong. The new cultivar, Shinsungppong, has following agronomic characteristics as compared with Sangilppong, which is known as a resistant cultivar to mulberry disease in Korea. It is belonging to Morus alba L. with mixed shapes from the ovate to 5 lobated leaf shape, sprouting in spring nearly the same to the Sangilppong (Morus alba L.), high leaf yielding by 7% compared to Sangilppong (Morus alba L.). It is adaptable to everywhere except the places where cold damage frequently in Korea. Sangilppong is recommended to rear silkworms not only in spring but also in autumn besides for young silkworms.

• Journal of Sericultural and Entomological Science
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• v.46 no.1
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• pp.12-17
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• 2004

New triploid mulberry cultivar, Suilppong was bred among selected lines from F$_1$ seedlings obtained by crossing the female, artificial tetraploid No. 411 which obtained from Chungilppong seedlings, and the male, Kugsang 21. Local adaptability test has been carried out at four places (Suwon, Kongju, Jeonju and Jangsung) for five years since 1997. Leaf quality was tested by silkworm rearing for two silkworm rearing seasons (spring and autumn) at Suwon in 2000. Suilppong was recognized to be superior in productivity to control cultivar, Kaeryangppong. The new cultivar, Suilppong, has following agronomic characteristics as compared with Kaeryangnppong, which is leading cultivar widely cultivating in Korea. It is belonging to Morus alba L. with mixed shapes from the ovate to 5 lobated leaf shape, sprouting in spring nearly the same to the Kaeryangppong (Morus alba L.), high leaf yielding of 20% compared to Kaeryangppong (Morus alba L.). It is adaptable to everywhere except the places where cold damage occurs frequently in Korea. Suilppong is recommended to rear silkworms not only in spring but also in autumn besides for young silkworms.

• Journal of the Korean earth science society
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• v.36 no.7
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• pp.643-648
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• 2015

Equations that could estimate the local magnitude of historical earthquakes, being difficult to calculate, in Sino-Korea craton was obtained using instrumental earthquake data for 22 Korean and 46 northeastern Chinese events. The obtained equations from intensity $I_0$ is $M_L=1.7+0.57{\times}I_0$. The equation from felt area FA for the Korean Peninsula is $M_L=4.29-1.34{\times}log(FA)+0.28{\times}log^2(FA)$. When the information on earthquake damage, effects, and felt area is all recorded at the same time, the former equation of intensity is more feasible than that of felt area due to uncertainty in earthquake felt area.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1398-1408
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• 2003

Tensile and LCF(low cycle fatigue) tests were carried out in air at wide temperature range 20$^{\circ}C$-750$^{\circ}C$ and strain rates of 1${\times}$10$\^$-4//s-1${\times}$10$\^$-2/ to ascertain the influence of strain rate on tensile and LCF properties of prior cold worked 316L stainless steel, especially focused on the DSA(dynamic strain aging) regime. Dynamic strain aging induced the change of tensile properties such as strength and ductility in the temperature region 250$^{\circ}C$-600$^{\circ}C$ and this temperature region well coincided with the negative strain rate sensitivity regime. Cyclic stress response at all test conditions was characterized by the initial hardening during a few cycles, followed by gradual softening until final failure. Temperature and strain rate dependence on cyclic softening behavior appears to result from the change of the cyclic plastic deformation mechanism and DSA effect. The DSA regimes between tensile and LCF loading conditions in terms of the negative strain rate sensitivity were well consistent with each other. The drastic reduction in fatigue resistance at elevated temperature was observed, and it was attributed to the effects of oxidation, creep and dynamic strain aging or interactions among them. Especially, in the DSA regime, dynamic strain aging accelerated the reduction of fatigue resistance by enhancing crack initiation and propagation.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.407-412
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• 1988

In order to increase the tryptophan productivity of E. coli SB1007, a mutant resistant to sulfanilamide was isolated and then a tyrosine auxotroph TY-90 was derived from the sulfanilamide-resistant mutant SA3-39-16. In the test-tube culture a quantitative amount of tryptophan was accumulated in strain TY-90 but in a jar fermentor culture the productivity was lower as compared to the level obtained by the parent strain. From the double auxotrophic mutant SB2756, a revertant resistant to 2, 000$\mu\textrm{g}$/$m\ell$ of $\beta$-thienylalanine, TA 40-10, was selected and then phenylalanine auxotrophs were derived from the revertant strain TA-40-10. One of the phenylalanine auxotrophs, TP-4, accumulated 3.7g/$\ell$ of L-tryptophan after 71-hr cultivation in a jar fermentor experiment.

• Archives of Pharmacal Research
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• v.27 no.6
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• pp.676-681
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• 2004

Acetyl-L-camitine (ALC), a naturally occurring endogenous compound, has been shown to improve the cognitive performance of patients with senile dementia Alzheimer＇s type, and to be involved in cholinergic neurotransmission. Because ALC is an endogenous compound, valida-tion of the analytical methods of ALC in the biological fluids is very important and difficult. This study was presented validation and correction for plasma ALC concentrations and pharmacok-inetics after oral administration of ALC to human volunteers. ALC concentrations in human plasma were corrected by subtracting the concentration of blank plasma from each sample. Precision and accuracy (bias %) for uncorrected ALC concentrations were below 2.6 and 6.5% for intra-days, and 4.0 and 9.4% for inter-days, respectively. Precision and accuracy (bias %)for corrected ALC concentrations were below 10.9 and 6.0% for intra-days, and 10.5 and 16.9% for inter-days, respectively. Quantitation limit was $0.1{\;}\mu\textrm{g}／mL$. After oral administration of a 500 mg ALC tablet to 8 healthy volunteers, the principle pharmacokinetic parameters were 4.2 h of the half-life$ (t_{1/2},{\beta})$, the area under the curve $(AUC_{0{\rightarrow}8){\;}of{\;}9.88{\;}\mu\textrm{g}{\cdot}h/mL$, and 3.1 h of the time ($T_{max}$) to reach $C_{max}$. This study first describes the pharmacokinetic study after oral admin-istration of a single dose of ALC in human volunteers.