• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.223-223
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• 2005

• Journal of Ginseng Research
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• v.20 no.2
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• pp.168-172
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• 1996

Ginsenoside Rb,, at a concentration of 10 $\mu\textrm{g}$/ml and over, initiated the cycle of oscillation of ion flux in erythrocytes after the cells had been treated with a protonophore, carbonyl cyanide p-trifluoro-methoxyphenyl hydrazone (FCCP) and then with a $Ca^{2+}$ ionophore, A23,3,. Its action was similar to the additional portion of $Ca^{2+}$-ionophore or $Ca^{2+}$ ion to the erythrocytes. Effects of $Rg_1$ and Rf were different from that of Rb,. They did not induce the oscillation. They, however, increased the extracellular $K^{+}$ concentration and pH without returning to the initial state in the erythrocytes processed with FCCP and $A_{23187}$. We established that ginsenosides from 20-(5)-panaxatriol family induced the membrane hyperpolarization in erythrocytes, which was attenuated by the pretreatment of $Rb_1$, a major component of 20-(5)-panaxadiol.

• The Plant Pathology Journal
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• v.38 no.2
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• pp.90-101
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• 2022

Pathogenicity of eight Bacillus strains to seedlings of four cotton cultivars was evaluated under greenhouse conditions. Each of the tested cultivars was individually treated with powdered inoculum of each bacterial strain. Untreated seeds were planted as control treatments in autoclaved soil. Effects of the tested strains on levels and activities of some biochemical components of the infected seedlings were also assayed. The biochemical components included total soluble sugars, total soluble proteins, total free amino acids, peroxidase, polyphenol oxidase, phenols, and lipid peroxidation. ANOVA showed that Bacillus strain (B) was a very highly significant source of variation in damping-off and dry weight. Cotton cultivar (V) was a nonsignificant source of variation in damping-off while it was a significant source of variation in dry weight. B × V interaction was a significant source of variation in damping-off and a nonsignificant source of variation in dry weight. Bacillus strain was the most important source of variation as it accounted for 59.36 and 64.99% of the explained (model) variation in damping-off and dry weight, respectively. The lack of significant correlation between levels and activities of the assayed biochemical components and incidence of damping-off clearly demonstrated that these biochemical components were not involved in the pathogenicity of the tested strains. Therefore, it was hypothesized that the pathogenicity of the tested strains could be due to the effect of cell wall degrading enzymes of pathogenic toxins. Based on the results of the present study, Bacillus strains should be considered in studying the etiology of cotton seedling damping-off.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.532-538
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• 2008

For the newly isolated $H_2$-producing chemoheterotrophic bacterium Citrobacter amalonaticus Y19, anaerobic glucose metabolism was studied in batch cultivation at varying initial glucose concentrations (3.5-9.5 g/l). The carbon-mass and energy balances were determined and utilized to analyze the carbon metabolic-pathways network. The analyses revealed (a) variable production of major metabolites ($H_2$, ethanol, acetate, lactate, $CO_2$, and cell mass) depending on initial glucose levels; (b) influence of NADH regeneration on the production of acetate, lactate, and ethanol; and (c) influence of the molar production of ATP on the production of biomass. The results reported in this paper suggest how the carbon metabolic pathway(s) should be designed for optimal Hz production, especially at high glucose concentrations, such as by blocking the carbon flux via lactate dehydrogenase from the pyruvate node.

• Korean Chemical Engineering Research
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• v.48 no.5
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• pp.561-567
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• 2010

Silylated waterborne polyurethane was synthesized by capping the NCO groups of polyurethane prepolymer, prepared from isophrone diisocyanate, poly(tetramethylene glycol) and dimethylol propionic acid, with aminopropyl triethoxysilane. Subsequently, it was mixed with colloidal silica to prepare silylated waterborne polyurethane/silica nanocomposites. The average sizes of nanocomposite particles, measured by dynamic light scattering, showed almost the same value, irrespective of increasing silica content. However, the prepared nanocomposites showed better thermal stability than pure waterborne polyurethane.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.178-178
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• 1996

Hepatitis B virus (HBV) infection is one of the serious problems in Southeast Asia including Korea because it causes chronic hepatitis, which can easily be transformed In fatal conditions such as cirrhosis and hepatoma. Even though lots of informations on structural characteristics and gene expression mechanisms have been accumulated, the mechanism for HBV-induced hepatocellular injury which is believed to be the consequences of the immunological response is not well understood. In order tn perform immunopathological studies for prevention and treatment of HBV infection, we designed transgenic mice as a disease model which can mimic HBV infection, In this study, a promoter-HBV DNA fragment for the preparation of HBV transgenic mice has been constructed. To add a proper enzyme site on 5' end of HBV gene, total HBV (subtype adr) gene was inserted into BamHI site of pBluescript SK vector and reextracted by PstI-SacI treatment A liver-specific promoter, rat ${\alpha}$ 2u globulin gene promoter, was insrted to pBluescript SK vector and reextracted by BamHI-PstI treatment, Promoter-HBV DNA was constructed by ligation of two fragments using identical PstI sites. For large scale production of promoter-HBV DNA, it was inserted to BamHI-SacI site of pBluescript SK vector.

• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.993-997
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• 2003

Response surface methodology was applied to find the optimum conditions for the production of DXAMase (containing both dextranase and amylase activities) based on the cultivation variables (pH, temperature, and agitation rate). The experimental values from the model equation conceded with predicted values in which the predicted values for dextranase and amylase activities were 2.26 and 3.52 U/ml at pH 4, $28^{\circ}C$, 235 rpm, and the corresponding experimental values were 2.41 and 3.68 U/ml, respectively.

• Korean Chemical Engineering Research
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• v.48 no.4
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• pp.428-433
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• 2010

Waterborne polyurethane(WPU) was synthesized from isophorone diisocyanate(IPDI), poly(tetramethylene glycol)(PTMG), dimethylol propionic acid(DMPA), triethylamine(TEA), ethylenediamine(EDA) and 3-aminopropyl triethoxysilane(APS) as a coupling agent. Subsequently, WPU/silica nanocomposites with different silica contents(0 to 8 wt%) were prepared by performing sol-gel reactions with tetraethylorthosilicate in the WPU matrix. The average particle size of the nanocomposite solutions increased with increasing TEOS content. Also, the prepared nanocomposites showed better thermal stability than pure WPU.

• Korean Chemical Engineering Research
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• v.48 no.4
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• pp.434-439
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• 2010

NCO terminated polyurethane prepolymers were synthesized from isophorone diisocyanate(IPDI), poly(tetramethyleneglycol)(PTMG) and dimethylol propionic acid(DMPA). Subsequently, aminosilane terminated prepolymers were prepared by capping the NCO groups of polyurethane prepolymers with different moles of aminopropyl triethoxysilane(0~0.02 mole) as a coupling agent. The average particle size of the silylated polyurethane solutions increased with increasing APS content. Also, the prepared coating films showed better thermal stability and pencil hardness than pure waterborne polyurethane.

• KSBB Journal
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• v.30 no.6
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• pp.257-267
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• 2015

Insects are the most successful organisms on earth in terms of their diversity and adaptability. Insect biotechnology using this insect resource is an emerging area for future biotechnology with various applications. Insect resources have long been used to make food and/or functional food, feed, cosmetics as well as medicine and industrial ingredients. Recently, one of the most well-known industrial material from insect is spider silk that could be commercialize in near future. The insect cell lines have been used to express recombinant proteins that were difficult to be functional expression. For public purpose, while, the insect could be good amenity source and plant farming, so leisure resource. Only the interdisciplinary research will guarantee the successful story for insect biotechnology. And biochemical engineers should used insect as a bioresource for new products with applications in medicine, agriculture, and industrial biotechnology in near future. This review will cover state-of-the art of this field and the research and application areas of insect biotechnology and the possible role of biochemical engineer for the development of the future biotechnology using this bioresource.