• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.121-126
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• 1999

Calli were induced from the petiole explants of Pimpinella brachycarpa on MS medium supplemented with 0.5 mg/L 2,4-D and 0.1 mg/L BA after four weeks of culture. Compact clusters of small and dense cells among these calli were selected and suspension-cultured as the source of embryogenic calli. When transferred to MS medium with 0.1 mg/L NAA, the suspension-cultured cells grew to embryogenic callus. Somatic embryos derived from these embryogenic calli developed into plantlets. The cDNA library was constructed in the embryogenic callus and in order to screen the cDNA library, these cDNAs were plated at a density 1.5 $\times$ 10^5 plaques per 15 cm petridish. Among 19 clones showing preferential hybridization with petiole HD-Zip gene, five clones were obtained after second screening. Four clones among them, were highly homologous to P. brachycarpa shoot-tip Phz4 gene, but one clone, Phc5 was about 1.5 kb which has an extra 163 bp to 5' upstream of Phz4. The Phc5 was 1,531 bp containing poly A tails of 18 bases. ATG start codon for Phc5, was located at position 284 with an open reading frame of 906 by which encodes a polypeptide of 302 amino acids. The Phc5 protein revealed that the polypeptides between 135 and 195 contain a homeodomain as the `leucine zipper' motif.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.203-211
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• 2000

In this study to produce large-scale scopolamine we were examined in the tumor calli of Datura metel L. induced by Agrobacterium tumefaciens $Ery{101}$. The growth and scopolamine contents of tumor calli were higher under light condition than in dark. The optimum condition of growth and scopolamine production were fluence rate of 16 $\mu$mol $m^{-2}s^{-1}$, spectra of red light region and 16 hour light periods on 50 mL SH liquid medium in 4 weeks culture. To increase of the scopolamine contents in tumor calli, the optimum concentration of nitrogen source were 1.8 mM NH$_4$+ and 40 mM NO$_3$. The optimum elicitor concentration for production of scopolamine were 10 mg/L chitosan and 15 mg/L yeast extract. The effect of precursors were good at the concentration of 0.2 mM tropine and 0.3 mM tropic acid, respectively. In order to increase of growth and scopolamine contents. we induced mutant from Datura metel L. tumor callus. Mutants of tumor calli were obtained by 3 Krad, 4 Krad and 6 Krad of ${60}^Cor-ray$. Among them, 3 Krad tumor callus was excellent on the growth and teratoma induction. The 4 Krad tumor callus was negligible for both growth and teratoma induction. But the 6 Krad tumor callus was the best in growth and teratoma induction. The formation of the mutant calli can be enhanced through hormonal combination of 1 mg/L 2,4-dichlorophenoxyacetic acid and 0.5 mg/L benzyladenine. We carry out selection mutant tumor calli for high content tropane alkaloid and suspension cultures for scopolamine production.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.1-8
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• 1996

A one-stage, continuous-flow bioreactor with both immobilized and suspended cells was used to investigate the roles of lipid supplements in ethanol production by Saccharomyces cerevisiae. The reactor performance and the level of alcohol dehydrogenase(ADH) activities of the suspended cells, grown under various conditions, were measured. When ergosterol and/or oleic acid were added with surfactants to the yeast culture grown under non-aerated conditions, remarkable increases in ethanol production and cell growth was achieved, but specific ADH activities were not affected. Especially, no difference of specific ADH activities of the suspended cells grown under aerated and non-aerated condition was observed. The addition of the surfactant as a supplement also resulted in significant increases in ethanol production, cell growth, and specific ADH activity. When ergosterol and oleic acid were added to the yeast culture exposed to higher ethanol concentration($>40\;g/{\ell}$) level, ethanol production, cell growth, and specific ADH activity were increased, but the addition of surfactant was as effective as at lower ethanol concentration level. The results indicated that lipid supplements were more effective at higher ethanol concentration level than at lower ethanol concentration level during ethanol production. ADH isozyme patterns of the yeast cultures grown under various conditions on starch gel electrophoresis showed only one major band, probably ADH I. The migrating distance of the major isozyme, however, varied slightly according to the culture conditions of the cells. No apparent correlation was found between specific ADH activity and amount of ethanol produced. Cell mass was more important factor for ethanol production than specific ADH activity of the cells.

• KSBB Journal
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• v.11 no.4
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• pp.411-419
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• 1996

In this research, an extractive production system for alkaloids, where production and some degree of separation occur simultaneously, was developed in a way that the fast removal of alkaloid produced from the suspension cultures was done by capturing alkaloid with cyclodextrins. The alkaloid production was substantially enhanced up to 40 fold when the solid cultures of E. califonica cells treated with ${\beta}$-cyclodextrin compared to the control. The enhancement of alkaloid production was also observed in the suspension cultures. Interestingly, the production pattern seemed to change when the cultures were treated with ${\beta}$-cyclodextrin so that the major part of the alkaloids in the treated cultures was present in the medium, while the non-treated cultures produced the alkaloids intracellularly. ${\beta}$-cyclodextrin was the most effective one in terms of the alkaloid production among the cyclodextrilns(${\alpha}$-cylodextrin, ${\beta}$-cyclodextrin and ${\gamma}$-cyclodextrin) tested in the suspension cultures. ${\beta}$-cyclodextrin showed no adverse effect on the cell growth. The most effective concentration of ${\beta}$-cyclodextrin was observed around 1.5% (w/v) in the suspension cultures. The formation of the inclusion complex of the alkaloids with ${\beta}$-cyclodextrin in the suspension cultures was confirmed by detecting the shift of UV absorbance from 274 nm to 282 nm with a UV spectrophotometer.

• KSBB Journal
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• v.14 no.5
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• pp.534-538
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• 1999

For the optimization of operating conditions for plant cell suspension culture in bioreactors, effects of bioreactor types, various kinds of impellers, and aeration rates were examined using Nicotiana tabacum cells as a model system. Stirred tank bioreactor and airlift bioreactor were used for the comparison of bioreactor type. Growth rates in both bioreactors were lower than in shake flasks. In terms of final cell concentration, stirred tank bioreactor supported a little bit better growth compared to airlift bioreactor. Impeller type did not affect cell growth significantly, but it was apparent that cell size index decreased in the case of using hollowed paddle impeller. When the aeration rate was maintained at 0.3 vvm, cell growth was the best. At above 1.0 vvm, growth inhibition as well a browning was noticed. In addition, it was found that cell size index reduced proportionally to the increased of aeration rate.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.478-482
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• 2004

Suspension culture of Schisandra chinensis for production of gomisin J was perfomed in bioreactor. The inoculum size and initial sucrose concentration had significant effect on the cell growth and gomisin J accumulation. The maximum dry cell weight $(DCW;\;43.5\;g/{\ell})$ and gomisin J content $(0.71\;{\times}\;10^{-3}\;{\mu}g/g\;DCW)$ were obtained at inoculum size of 100 g fresh cell weight (FCW) per liter and MB5 medium containing 6% sucrose after 8 weeks of culture. The effect of oxygen supply on the cell growth and gomisin J accumulation was also investigated in an airlift-type bioreactor. The optimal cell growth and gomisin J content was obtained under 0.5 vvm. The productivity of gomisin J was 0.7 fold in bioreactor culture lower than that obtained in a flask cultivation.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.289-291
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• 1999

Hypocotyl explants from 7 days old seedlings of one $F_1$ hybrid cultivar and two pure lines of cucumber formed embryogenic calli at frequencies of up to 8% when cultured on Murashige and Skoog medium (MS) supplemented with 1 mg/L 2,4-D for 3 weeks. Embryogenic calli gave rise to somatic embryos. When slices of somatic embryos were cultured on the same medium for 4 weeks, they formed embryogenic calli. Embryogenic cell suspension cultures were established with embryogenic calli in MS liquid medium with 1 mg/L 2,4-D. Embryogenic potential of cell suspension cultures was maintained by subculturing every seven days. When the level of 2,4-D in the medium was lowered to 0.2 mg/L by diluting with liquid MS basal medium, embryogenic cell suspension cultures underwent development into numerous somatic embryos. When plated onto MS basal medium, over 95% of somatic embryos developed into plantlets. Plantlets were transplanted to potting soil and grown to maturity.

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

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.390-393
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• 2000

In this work, effects of trehalose on the recovery of bioluminescence and viability of luxAB-containing recombinant bacteria were investigated. In case of a recombinant, UV2, only 2.5% of bioluminescence and 2.7% of cell viability were restored after 3.5hr of freeze-drying without trehalose, which implies that cells were heavily damaged during the dehydration. To improve these losses, trehalose was added before freeze-drying on different modes. Trehalose increased the bioluminescence and viability of freeze-dried UV2 in all conditions tested and it was observed that addition of trehalose into the broth(final concentraion, 0.08M) for 15min before the freeze-drying resulted in 45% of bioluminescence and 50% of cell viability. For the other luminescent recombinant, YH9, trehalose showed a similar efficacy.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.284-287
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• 2003

Effects of ultrasound on cell growth and the production of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) were investigated using transgenic Nicotiana tabacum cell suspension cultures. The culture suffered a slight growth depression immediately after the sonication, but gradually recovered to normal growth within 2 days. When the cells were exposed to ultrasound, the level of secreted hGM-CSF was 2.14 times higher than that in normal condition. From the beginning to 6 days of culture, production of secreted hGM-CSF was higher than that of control and then decreased. At the end of culture, however, hGM-CSF was considerably increased up to 36.7%. In the case of intracellular hGM-CSF, the level was slightly higher than that obtained in normal condition. Total hGM-CSF production was 31.5% higher than that of control culture after 6 days. The highest amount of hGM-CSF was $34.9\;{\mu}g/L$.