• Journal of Plant Biology
• /
• v.36 no.3
• /
• pp.211-218
• /
• 1993

Plant regeneration was accomplished from protoplast culture of rice (Oryza sativa L. cv. Taebaeg). Embryogenic callus was induced from mature seed on MS medium containing 5 mM proline, 2.5 mg/L 2,4-D, 30 g/L sucrose in the dark at 28$^{\circ}C$ and used to establish embryogenic cell suspension culture. Suspension cells were subcultured every one week in N6 medium supplemented with 5 mM proline, 200 mg/L casein hydrolysate, 2.5 mg/L 2,4-D and amino acids of AA medium. Suspension cultures were composed of cells that were densely cytoplasmic, potentially embryogenic and were at least maintained for more than 6 months in liquid medium. Protoplasts were isolated from fast-growing suspension culture cells and cultured in a slightly modified KpR medium by mixed nurse culture. Isolated protoplasts began to divide within 5~7 days and thereafter, protoplast-derived calli were sequentially transferred to callus proliferating medium that soft agar MS medium contained 2 mg/L 2,4-D and produced distinct embryogenic cells. Microcolonies were then transferred to solid medium which consisted of MS medium containing 5 mg/L kinetin, 1 mg/L NAA, 1 mg/L ABA, 30 g/L sucrose and 10 g/L sorbitol under fluorescent light. Mulitple shoots of 4~5 per callus emerged and were transferred to hormone-free MS medium for root initiation. Thereafter, The plantlets were transferred to pots of soil to mature in the culture room.

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.392-392
• /
• 2005

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2002.04b
• /
• pp.160-160
• /
• 2002

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.10 no.2
• /
• pp.162-165
• /
• 2005

A series of fluorine and hydroxyl containing jasmonate derivatives, which were chemically synthesized in our institute, were investigated for their effects on the biosynthesis and heterogeneity of ginsenosides in suspension cultures of Panax notoginseng cells. Com-pared to the control (without addition of elicitors), $100{\mu}M$ of each of the jasmonate was added on day 4 to the suspension cultures of P. notoginseng cells. It was observed that, jasmonates greatly enhanced the ginsenoside content and the ratio of Rb group to Rg group (i.e. $(Rb_1\;+\;Rd)/(Rg_1\;+\;Re)$ in the P. notoginseng cells. Some of the synthetic jasmonates, such as pentafluoropropyl jasmonate (PFPJA), 2-hydroxyethyl jasmonate (HEJA) and 2-hydroxye-thoxyethyl jasmonate (HEEJA), could promote the ginsenoside content to $2.55\;\pm\;0.11,\;3.65\;\pm\;0.13\;and\;2.94\;\pm\;0.06$mg/100 mg DW, respectively, compared to that of $0.64\;\pm\;0.06$mg/100 mg DW for the control and $2.17\;\pm\;0.04$ mg/100 mg DW by the commercially available methyl jasmonate (MJA); and they could change the respective Rb:Rg ratio to $1.60\;\pm\;0.04,\;1.87\;\pm\;0.01\;and\;1.56\;\pm\;0.05$, compared to that of $0.47\;\pm\;0.01$ for the control and $1.42\;\pm\;0.06$ by MJA. The results suggest that suitable esterification of MJA with fluorine or hydroxyl group could in-crease the elicitation activity to induce plant secondary metabolism. The information obtained from this study is useful for hyper-production of heterogeneous products by plant cell cultures.

• Plant Biotechnology Reports
• /
• v.5 no.4
• /
• pp.367-373
• /
• 2011

Linum album accumulates anti-tumor podophyllotoxin (PTOX) and its related lignans, which were originally isolated from an endangered species Podophyllum. In the present study, we examined the effects of five fungal extracts on the production of lignans in L. album cell cultures. Fusarium graminearum extract induced the highest increase of PTOX [$143{\mu}g\;g^{-1}$ dry weight (DW) of the L. album cell culture], while Rhizopus stolonifer extract enhanced the accumulation of lariciresinol up to $364{\mu}g\;g^{-1}$ DW, instead of PTOX. Typical elicitors, such as chitin, chitosan, or methyl jasmonate (MeJA), were shown to be less effective in lignan production in L. album cell cultures. These results verified the advantages of fungal extracts to increase lignan production in L. album cell culture, and suggested potential on-demand metabolic engineering of lignan biosynthesis using differential fungal extracts.

• Journal of Plant Biotechnology
• /
• v.4 no.3
• /
• pp.123-127
• /
• 2002

Herbicide tolerant rice (Oryza sativa L. cv. Ilpumbyeo) cell lines were selected from $\gamma$-ray-irradiated anther-derived cell cultures. The anther-derived cell clusters were small (300 to 400 ${\mu}{\textrm}{m}$ in diameter) and uniform ones that were screened by miracloth filtering. The cell suspensions were very efficient to plate one layer onto agar medium and to screen target cell lines. Herbicide tolerant cell lines were selected by 5 mg/L cyhalofop butyl (CHB) treatment by using the small cell suspensions on agar N6 medium containing 1 mg/L 2,4-D and 0.2 mg/L kinetin. Of the cell lines, one line (CHB-1) showed stable tolerance at 10 mg/L concentration after 6-month culture without herbicide suspension. Growth stability of CHB-1 was similar to that of control cell line on 10 mg/L CHB containing medium. In this experiment we established herbicide tolerant cell line selection system by using anther-derived uniform-cell suspensions with $\gamma$-ray-irradiation.

• Journal of Plant Biology
• /
• v.33 no.2
• /
• pp.87-96
• /
• 1990

The role of S-adenosylmethionine (SAM) as an intermediate in interrelation between polyamine and ethylene biosynthesis was studied in suspension cultures of Nicotiana tabacum L. Exogenous SAM stimulated the polyamine and ethylene biosynthesis in 4 day-cultured cells, which were in active cell divisions, and 10 day cultured cells, which went on with active cell elongation and senescence. SAM-induced ethylene production was more effective in 10 day-cultured cells than in 4 day-cultured cells, but SAM-induced polyamine biosynthesis was more effective in 4 day-cultured cells than in 10 day-cultured cells. Polyamine contents were increased by the blockage of ethylene biosynthetic pathway in the conversion of SAM to ethylene via 1-aminocyclopropane-1-carboxylinc acid (ACC) with aminooxyacetic acid (AOA). Also, ethylene production was increased by the inhibitors of polyamine biosynthesis such as methylglyoxal bis-(guanylhydrazone) (MGBG), dicyclohexylamine (DCHA), $\alpha$-difluoromethylarginine (DFMA) and $\alpha$-difluoromethylorinithine (DFMO). These results suggest that there may be interrelations between polyamine and ethylene biosynthesis for the competition of SAM and the inherent mechanism of switch on-off in polyamine and ethylene biosynthetic activity with the progress of cell growth and senescence.

• KSBB Journal
• /
• v.6 no.4
• /
• pp.385-388
• /
• 1991

Embryogenic cell suspension cultures of B. striata were established as transferred selected embryogenic callus into liquid medium. Protoplasts isolated from embryogenic cell suspensions were electroporated in buffered solutions containing plasmid DNA of pBI121. Transient GUS (beta-glucuronidase) activity measurement and selection for kanamycin resistent showed that expression of foreign genes and stable transformation were achieved. GUS transient gene expression was increased by increasing DNA concentration of pBI121 plasmid and affected by the level of the applied voltage. An optimal level of GUS activity was obtained after electroporation with a pulse of 200-300 voltage/1180 uF. Protoplast viability was up to the 80% at the optimal voltage.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.351-355
• /
• 2003

Response surface methodology was employed to study the interactive effect of sucrose, nitrogen, temperature and to optimize their levels to enhance the production of human granulocyte-macrophage colony-stimulation factor from Nicotiana tabacum cell suspension cultures. A 15-runs Box-Behnken design including three center points was the response surface method selected for the initial set of experiments. The analysis of the data from the Box-Behnken experiments showed interactive effects of sucrose:nitrogen, sucrose:temperature and nitrogen:temperature. The optimal combinations of sucrose, nitrogen and temperature for hGM-CSF production from surface plot were sucrose 90 g/L, nitrogen 41 mM and 22$^{\circ}C$, respectively. The optimization of there factors enhanced the hGM-CSF production by 2 times because high sucrose concentration stimulated the secretion of hGM-CSF and low temperature prevented hGM-CSF degradation in media by pretenses.

• Journal of Plant Biotechnology
• /
• v.29 no.3
• /
• pp.185-188
• /
• 2002

Off-white, friable embryogenic calluses were formed on the internal integument of mature seeds of yuzu (Citrus junos) cultured on Murashige and Skoog's basal medium at a frequency of 1.2%. Embryogenic calluses were proliferated when cultured on medium with 1 mg/L 2,4-D. Upon transfer to medium with 0.1 mg/L kinetin, embryogenic calluses produced numerous somatic embryos. Embryogenic suspension cultures were established by placing embryogenic calluses into liquid medium with 1 mg/L 2,4-D. When plated onto medium with 0.5 mg/L ABA, embryogenic cells developed into somatic embryos at a high frequency, and then regenerated into plantlets. Plantlets were successfully transplanted to potting soil and grown in a greenhouse.