• Journal of Plant Biotechnology
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• v.30 no.2
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• pp.135-141
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• 2003

Peroxiredoxin(Pix) are large family of peroxidases that reduce alkyl hydroperoxides and hydrogen peroxide. A cDNA clone (referred to as swPrxl) encoding Pix was from a sweetpotato cDNA library constructed from suspension-sultured cells, and its expression was investigated in terms of stress. The swPrxl contained an open reading frame (ORF) encoding mature protein of 193 amino acids with calculated molecular mass of 20.8kDa. The predicted amino acid sequence of swPrxl has two conserved cysteines that are essential resicues for the reduction of peroxides. It showed high amino acid sequence homology ot PixIIF of Arabidopsis (77%) and putative Prx of rice(72%). RNA gel-blot analysis showed that swPrxl gene was expressed dominantly in leave among intact tissues, and also highly detect in suspension-cultured cells. Interestingly, the level of swPrxl transcripts was almost the same regardless of the growth stage in suspension culture. Furthermore, the transcription level of swPrxl gene was not significantly changed in response to various stress treatments such as wounding, extreme temperature and stress-related chemicals RT-PCR analyses.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.309-314
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• 1994

To develop simple and efficient transformation methods of monocotyledonous plane, electroporation-mediated delivery of DNA into intact embryogenic cell clumps was investigated in zoysiagrass and rice. Calli of zoysiagrass, induced from 3-week-old immature embryos, were suspension-cultured in MS basic medium supplemented with 1.0 mg/t 2.4-D and used for elechuporation. Calli, derived from immature inflorescences of 20 mm lenth of rice, were also suspension-cultured on N6 basic medium supplemented with 1.0 mg/L 2.4-D. Suspension-cultured embryogenic cell clumps were electroporated in liqid MS medium added with a Plasmid DNA (30 $\mu\textrm{m}$/ml), pGA1074, encoding ${\beta}$-glucuronidiase (GUS). DNA delivery into the cells through cell walls and cell membrane was confirmed by the transient expression of the GUS gene. Cell clumps of zoysiagrass and rice, electroporated with 400 volt at 800 pF capacitance, expressed GUS gene activity at a mean frequency of 25 units (one unit = one clony of blue cells) per 200 ${\mu}\ell$ of packed cell volume. Untreated cells and healed non-embryogenic cells did not exhibit GUS activity These results indicate that electroporation-mediated transformation can use intact embryogenic cells (thus avoiding the use protoplasts) in zoysiagrass and rice.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.133-136
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• 2000

To evaluate the biological effects of dykellic acid, a novel apoptosis inhibitor, isolated from microorganism on the plant cells, the cell growth, protein contents, and superoxide dismutase (SOD) activity were investigated in suspension cultures of tobacco photomixotrophic cultured (PM) cells on 12 days after different concentration of chemical treatment. The cells were cultured in MS medium containing 0.7 mg/L 2,4-D, 0.3 mg/L kinetin, 30 g/L sucrose and 200 mM NaCl at $25^{\circ}C$ in the light (100 rpm). Dykellic acid strongly inhibited the cell growth by evaluating the cell fresh wt and the ion conductivity in the medium ($IC_{50}$/, about 20 $\mu$M). The results as inhibition of cell growth and cell wall damage were same. The compound significantly increased the protein contents and the SOD specific activity in proportion with the dosage. The results suggested that dykellic acid may have biological activity in plant cells and tobacco PM cells may be suitable biomaterials for in vitro evaluation of the biological activity of natural products.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.494-499
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• 2004

A method for long-term conservation of somatic embryos of Eleutherococcus senticosos was described. Suspension cultured globular somatic embryos were successfully conservated for 36 months at $4^{\circ}C$. The embryos resumed growth within two weeks when returned to MS liquid medium containing $0.2\;mg/{\ell}$. 2,4-dichlorophenoxy acetic acid. The optimal condition for cell proliferation was achieved when somatic embryos cultured at $32^{\circ}C$ in 1/3 MS liquid medium, and about 1.2 g of embryogenic cell was induced from 150 globular embryos after 6 weeks of suspension culture. The embryogenic cells produced from these somatic embryos exhibited normal plant regeneration on auxin-free medium.

• Journal of Plant Biology
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• v.32 no.4
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• pp.227-233
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• 1989

Single cells obtained from suspension culture of mature embryo-derived callus in wheat(Triticum aestivum L. cv Jang Kwang) were cultured to regenrated into the plantlet. Cell clusters and embryogenic calluses were efficiently developed from when the single cells clutured on the MS medium supplemented with 10${\mu}{\textrm}{m}$ 2,4-D. Upon transfer to hormone-free MS medium containing 10 mg/I AgNO3, embryogenic calluses gave rise to shoots, probably through somatic embryogenesis.

• Journal of Environmental Health Sciences
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• v.36 no.4
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• pp.271-278
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• 2010

The appearance of Asian Dust (AD) originating from China and Mongolia during spring each year is a meteorological phenomenon periodically observed in extensive regions of East Asia. According to a previous epidemiological study, AD has adverse effects on both human beings and ecosystems. In this study, we collected total suspension particles (TSP) in the AD period and Non-AD (NAD) period. We extracted organic components from TSP using dichloromethane (DCM), and the polyaromatic hydrocarbons (PAHs) were analyzed. The DCM extracts contained PAHs such as benzo(b)fluoranthene, benzo[g,h,i]perylene, benzo(k)fluoranthene, benzo(a)pyrene, and pyrene. No significant difference was observed in cytotoxicity of the DCM extracts from AD versus NAD when tested on the human bronchial epithelial cells, BEAS-2B. e also examined the toxic mechanisms of AD extracts in cultured BEAS-2B cells and RAW264.7 cells, and in BEAS-2B cells observed increased levels of reactive oxygen species (ROS), decreased glutathione (GSH), and induced caspase-3 activity. Increased expression of oxidative stress-related and inflammation- related genes were also observed in BEAS-2B cells, while nitric oxide (NO) levels were increased in RAW264.7 cells. Taken together, the results suggest that in these cultured cells, AD may induce cytotoxicity through oxidative stress and pro-inflammatory signals.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.6
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• pp.1212-1217
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• 2017

We constructed a population of myelinated cells with co-culture of neuronal cells and Schwann cells from DRG. Schwann cells and neuronal cells were isolated from dorsal root ganglion (DRG) in embryos of rat in vitro respectively. The cultured Schwann cells and cultured neuronal cells, respectively were co-cultured in a same plate. This procedure contains following four steps: first step of suspension of the embryonic dorsal root ganglion cells, second step of addition of anti-mitoticcocktail, third step of purification of dorsal root cells, and fourth step of addition of Schwann cells to dorsal root ganglion cells. These cells were performed accomplishment of myelination. This myelinated co-culture system was infected by Semliki forest virus and then induced demyelination processing in this myelinated co-culture. We identified myelination and demyelination processing using antibody of peripheral myelin protein 22 (PMP 22) meaning presence of myelinated neuron.

• Journal of Microbiology and Biotechnology
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• v.6 no.3
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• pp.209-212
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• 1996

A two-step cooling technique has been developed for cryopreservation of suspension cultured Scutellaria baicalensis cells. Efficient regrowth of cryopreserved cells was obtained in cryoprotected cells with a mixture of 1.5 M glycerol and 0.4 M sucrose in Schenk and Hildebrandt medium without pretreatment in high osmotic medium. Optimum freezing conditions were found to be a cooling rate of $0.5^{\circ}C$ min from $4^{\circ}C$ to $-40^{\circ}C$, and then retaining samples at $-40^{\circ}C$ for 30 min prior to plunging into liquid nitrogen. A regrowth rate of approximately 95$%$ was obtained after three month storage in liquid nitrogen. Callus cultures established from the cryopreserved cells were found to produce the same patterns of flavonoid accumulation and retain their baicalin producing activity.

• Korean Journal of Plant Tissue Culture
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• v.24 no.1
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• pp.57-61
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• 1997

We investigated changes in the superoxide dismutase (SOD) activity and SOD isoenzyme pattern in suspension cultures of tomato (Lycopersicon esculentum), which were compared with those of intact tomato plants. two grams (fr wt) of cells subcultured at 15-day intervals were inoculated into 50 mL MS medium containing l mg/L 2,4-D and 30 g/L sucrose in a 300 mL flask and maintained at $25^{\circ}C$ in the dark (100 rpm). The cell growth reached a maximum at 20 days after subculture (DAS), followed by a rapid decrease with further cultures. The cell colour changed from white to black from 23 DAS. The intracellular SOD activity (units/g cell dry wt) was significantly increased from 23 DAS and reached a maximum at 28 DAS (52,400 units), followed by a decrease with further cultures, whereas the extracellular SOD activity showed a maximum at 25 DAS (27,800 units/50 mL medium). The total SOD activity per flask showed a maximum at 25 DAS (35,700 units), in which the extracellular SOD activity occupied about 75%. The tomato cultured cells had four SOD isoenzymes and their patterns were well correlated with SOD activity without a qualitative change during the cell cultures. The intact tomato plants had an additional CuZnSOD isoenzyme, showing the different isoenzyme patterns from cultured cells.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.340-346
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• 2018

In this study, the effect of elicitors such as yeast extract (YE), methyl jasmonate (MeJA) and salicylic acid (SA) on the accumulation of eurycomanone in Eurycoma longifolia cell cultures were investigated. Suspension cells of E. longifolia was cultured in Murashige and Skoog (MS) medium supplemented with 30 g/L sucrose, 1.25 mg/L naphthaleneacetic acid (NAA) and 1 mg/L kinetin at a shaking speed of 120 rpm. Elicitors were added in the culture at different concentrations and times to stimulate eurycomanone accumulation in the Eurycoma longifolia cells. Eurycomanone content was determined by HPLC with a C18 column, flow rate of 0.8 mL/min, run time of 17.5 min, and a detector wavelength of 254 nm. The stationary phase was silica gel and the mobile phase was acetonitrile: $H_2O$. Non-elicited cells were used as the control. The study showed the effect of different elicitor concentrations, YE at 200 mg/L, MeJA at $20{\mu}M$ and SA at $20{\mu}M$ stimulated high production of eurycomanone. In which, treatment of $20{\mu}M$ MeJA after 4 days of culture resulted in the highest accumulation of this compound (17.36 mg/g dry weight), approximately 10-fold higher than that of untreated cells (1.70 mg/g dry weight).