• Journal of Ginseng Research
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• 제27권1호
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• pp.17-23
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• 2003

Agrobacterium-mediated transformation of American ginseng (Panax quinquefolius L.) with strain LBA 4404 containing a rice thaumatin-like protein gene is described. The selectable markers used were phosphinothricin acetyltransferase and hygromycin phosphotransferase genes. Epicotyl explants from seedlings were precultured for 5-7 days on Murashige and Skoog medium with ${\alpha}$-naphthaleneacetic acid and 2,4 dichlorophenoxyacetic acid at 10 ${\mu}$M and 9 ${\mu}$M, respectively (ND medium), prior to Agrobacterium infection. The explants were immersed in a bacterial suspension for 20 min. A post-infection co-culture period of 3-4 days was provided on ND medium. Selection for transformed calli was conducted on ND medium with 20 mg/L phosphinothricin followed by 100 mg/L hygromycin over an 8-month period. it transformation frequency of 24.8% was achieved at the callusing phase. The presence of the transgenes in calli was confirmed by Southern hybridization and polymerase chain reaction analysis. The expression of the thaumatin-like protein gene in ginseng calli was demonstrated by Western blot analysis. Somatic embryos were produced from both transgenic calli and suspension cultures, and plantlets were recovered that expressed the transgenic thaumatin-like protein gene.

• Journal of Plant Biology
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• 제33권4호
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• pp.259-269
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• 1990

Changes of peroxidase activity, polyamine content and ethylene production during somatic embryogenesis in suspension-cultured carrot (Daucus carota L.) cells were investigated. As compared with nonembyrogenic cells and their medium, embryogenic cells and their medium were characterized by higher levels of peroxidase at all times of culture period. Peroxidase in embryogenic cells showed higher oxidation activity of IAA than in nonembryogenic cells at the torpedo stage, but the IAA oxidation activity of peroxidase released into embryogenic medium was lower than that of peroxidase released into nonembryogenic medium. Peroxidase patterns of embryogenic and nonembryogenic cells showed three cathodic bands, and one anodic band, while peroxidase patterns released into embryogenic and nonembryogenic media did not show any anodic bands and the isoelectric points of cathodic peroxidase were pH 7.7, 7.5 and 6.6. Compared with nonembryogenic cells, polyamine content in embryogenic cells was increased by 15% at the torpedo stage, but polyamine ratio was constant, and ethylene production was extremely low at all times of culture period. Therefore, it is suggested that the peroxidase in embryogenic cells is correlated with embryogenesis by regulating hormone ratios through IAA oxidation, while the peroxidase isozyme patterns may be used as a biochemical marker of embryogenesis. The increase of polyamine content and the decrease of ethylene production suggest an interaction between polyamine and ethlyene during embryogenesis.

• Natural Product Sciences
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• 제3권1호
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• pp.71-74
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• 1997

Cell suspension cultures of Solanum mammosum transformed inoculated salicyl alcohol into salicin $(salicyl\;alcohol\;2-0-{\beta}-D-glucopyranoside)$. The highest level of salicin (59.3 mg/flask) in the cells was formed within 3 days after inoculating with salicyl alcohol (50 mg /flask containing 50 ml medium). The glucosylation capability of salicyl alcohol by cell suspension cultures of S. mammosum was relatively higher than that reported previously.

• 정보저장시스템학회논문집
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• 제6권1호
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• pp.12-17
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• 2010

Thermally-assisted magnetic recording (TAMR) is a potentially promising approach to increase the storage density of hard disk drive (HDD). However, TAMR has some issues such as temperature effects, media problems, thermal deformation and light delivery. In this research, we focused on light delivery. One of the powerful methods to deliver the light from laser diode to recording medium is the use of an optical fiber and a specially designed prism. However, the TAMR with optical fiber may have some flyability problems induced by the mounted optical fiber and prism. Also, the TAMR suspension using an optical fiber has high vertical and pitch stiffness. Therefore, p-torque is greatly increased by the optical fiber. Also, flying height (FH) of the slider with TAMR suspension can be largely changed by p-torque. Therefore, in this paper, we focus on the pitch static attitude (PSA) tolerance and the FH by PSA of the TAMR suspension. The FH is investigated using various errors and the PSA tolerance for TAMR suspension is proposed.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2002년도 제38회 학술심포지움
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• pp.48-60
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• 2002

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine that stimulates the production of granulocytes, macrophages, and white blood cells. The effects of osmotic pressure on secretion of human GM-CSF into the culture medium were investigated in suspension cultures of transgenic tobacco cells. An increase in osmotic pressure caused by the addition of mannitol decreased the cell size index, with the effect being more pronounced when cells were measured wet rather than dry. Increased osmotic pressure enhanced the secretion of hGM-CSF. At 90 g/L mannitol, the maximum concentration tested, hGM-CSF was present in the culture medium at 980 ug/L. As the concentration of mannitol increased, the total amount of protein secreted also increased, but was disproportionately enriched in GM-CSF NaCl, another osmoticum, had very similar effects on cell growth and hGM-CSF production, but did not cause enrichment for hGM-CSF Additionally, protein-stabilizing polymer was added to culture broth to enhance stability of secreted recombinant protein. Finally, above two method were applied together to maximize the productivity.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.631-638
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• 1998

Studies were made to elucidate the cell growth and the production of camptothecin and its derivatives in cell cultures of Camptotheca acuminata. High resolution HPLC chromatograms to analyze camptothecin and 10-hydroxycamptothecin in lactone and carboxylate forms were obtained with a fluorescence detector. Calli inductions were optimized with the young stem of explant on Schenk and Hildebrandt (SH) medium supplemented with 5 mg/l $\alpha$-naphthaleneacetic acid (NAA), 0.2 mg/l 6-benzylamino purine (BAP), 2.0% sucrose, and 0.5% agar. The hybrid medium, a mixture of SH and Murashige and Skoog (MS) salts, was developed for homogeneous suspension cultures without large cell aggregates. The optimum phytohormone concentrations for successful suspension cultures were 1.0mg/l of 2,4-D and 0.5 mg/l of kinetin. The highest growth in suspension cultures was observed when 49.7% (w/w) of the cells was composed of small aggregates which were below 0.1 mm in diameter. Time course changes of cell growth and camptothecin production showed that camptothecin accumulation was started at the end of the growth phase and the maximum content was obtained 10 days after inoculation. Yeast extract elicitor increased camptothecin accumulation 4 times. Methyl jasmonate and jasmonic acid also increased camptothecin production 6 and 11 times, respectively.

• Journal of Applied Biological Chemistry
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• 제57권1호
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• pp.61-63
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• 2014

Aged black garlic (ABG) was extracted with 20% ethanol and water (crude extracts) and fractionated into three categories (>10, 3-10, and <3 kDa). The effect of crude extract supplements on anti-My-10 hybridoma cell growth and IgG1 antibody production was investigated in suspension culture with a chemically defined protein-free medium. We observed that supplementation of ABG to the cell culture medium stimulated anti-My-10 hybridoma cell growth and production of IgG1 antibody, particularly with fractionated ABG of low molecular weight. The stimulation depended upon the concentration and the size of the fractionated ABG. We also found that the growth-promoting activity was not correlated with high antibody production. These results suggest that fractionated ABG is a novel and promising alternative as an animal cell culture supplement.

• Journal of Plant Biology
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• 제34권1호
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• pp.19-23
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• 1991

벼의 종자로부터 embryogenic callus를 유도하고 이로부터 개체로의 재분화를 유도하였으며, embroyogenic cell suspension culture를 통하여, 이로부터 원형질체를 분리, 배양하여 embryogenic callus를 형성하였다. 또한, 분리된 원형질체를 electroporation하였을 때 생존율(viability)에 미치는 여러 요인들을 조사하였다. 원형질체의 생존율은 voltage와 capactiance가 증가할수록 감소를 보였으며, HBM buffer에서 $4^{\circ}C$로 electroporation 하였을 때 생존율에 보다 효과적이었다.

• 생약학회지
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• 제25권1호
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• pp.28-30
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• 1994

The rate of growth and production of bioactive substances from Rehmannia glutinosa Liboschitz (Scrophulariaceae) were studied with the variation on the constituents of the culture media. The best growth was observed from MS basal medium containing 3.0 ppm NAA and 2.0 ppm kinetin. Carbohydrates (fructose, glucose and sucrose), phytosterols(${\beta}-sitosterol$, campesterol and stigmasterol) and carotenoid like substances were identified by GC-MS and TLC from the callus mass. However, catalpol was not detected from both solid and cell suspension cultures containing geraniol. Callus cultured Rehmannia glutinosa in the MS basal medium containing 0.1 ppm NAA and 0.1 ppm kinetin become differentiated to root.

• Journal of Plant Biology
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• 제37권3호
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• pp.263-269
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• 1994

Involvement of ethylene and Ca2+ on the induction of phenylalanine ammonia-lyase (PAL) was investigated in Daucus carota L. suspension culture system. Ethylene production started to increase about 3 h after glucan treatment. And the maximal induction of ethylene was preceded by PAL induction by 30 min. After the treatment of ethrel, PAL activity was increased. When cells were treated with glucan and Co2+, PAL activity was simultaneously reduced. Ethylene production was reduced dramatically in calcium-free medium, even though glucan was treated. PAL activity and ethylene producton was inhibited conspicuously when ethylene glycolbis($\beta$-aminoethyl ether) N,N,N',N'-tetraacetic acid (EGTA) was treated with glucan. Verapamil and trifluoperazine also inhibited PAL activity. When cells were treated with calcium ionophore A23187, PAL activity was increased in nontreated medium. We report here PAl activity is increased in related to ethylene production and involvement of Ca2+ in glucan-treated carrot suspension cells.