• Korean Journal of Medicinal Crop Science
• /
• v.7 no.4
• /
• pp.245-250
• /
• 1999

Callus growth of fusaric aicd-tolerance cell lines was different depending on fusaric acid concentrations. But callus growth on medium with fusaric acid was higher than that on medium without fusaric acid. Especially, RF-9, RF-11 and RF-15 showed high callus growth at $100\;{\mu}M$ fusaric acid. After subculturing on medium without fusaric acid for 5 weeks, fusaric acid -tolerant stability was investigated. Cell lines at $10{\mu}M$ fusaric acid were showed over 60% callus growth, callus growth rate at $100{\mu}M$ fusaric acid was decreased until 30-80% of control. Regeneration capacity of fusaric acid-tolerant cell lines was different depending on fusaric acid concentrations. Thirteen cell lines regenerated the shoot over at $50{\mu}M$ fusaric acid, and only two cell lines were not regenerated.

• Research in Plant Disease
• /
• v.15 no.3
• /
• pp.202-208
• /
• 2009

The genetically modified leaffolder-resistant (Cry1Ac1) rice plant was evaluated for the changes of resistance by comparing the occurrence of major diseases with a japonica type Korean rice variety, Nakdong which was the mother plant of the transgenic rice event, in greenhouse and field conditions. There was no difference in the occurrence of sheath blight and Helminthosporium blight between the two varieties in the fields. We couldn't find any difference of resistance for fungal blast and bacterial leaf blight by artificial inoculation in greenhouse. There was also no difference in the susceptibility to sheath blight in artificial inoculation tests confirming the results in the fields. The possibility of gene transfer of Bar and Cry1Ac1 from the genetically modified rice plant to naturally infected pathogens such as Fusarium moniliforme and Pyricularia oryzae in the field conditions was tested by PCR. And the possible transfer of those genes by continuous inoculation of Xanthomonas oryzae pv. oryzae and Rhizoctonia solani was also tested. However, we couldn't find any possibility of transfer of the genes in natural and artificial conditions.

• Journal of Veterinary Clinics
• /
• v.27 no.3
• /
• pp.232-239
• /
• 2010

Two cell lines derived from spontaneous canine mammary gland tumors were established and characterized. Mammary gland tumors from 9 years old pug and 9 years old toy-poodle dogs were collected by aseptic surgical resection and primary culture was performed. The histopathologic examination of tumors revealed adenocarcinoma and complex carcinoma and two dogs died from metastasis of the tumors. The tumor cells were subcultured over 60 times for more than 1 year and morphological consistency maintained. Light microscopic examination, growth curve, doubling time calculation, xenotransplantation to female nude mice, immunohistochemistry for wide spectrum keratin, vimentin, $\alpha$-smooth muscle actin and cytokeratin 8 was performed for characterization. The cell lines exhibited polygonal, elongated cell shape and cytoplasmic bridge and doubling time of 47.1 hrs and 18.6 hrs, respectively. Subcutaneous xenotransplantation to nude mice of the cells produced localized palpable mass within 4 weeks in 4 of 5 and 5 of 5 nude mice, respectively. In immunohistochemical examination one cell line showed strong positive against wide spectrum keratin and cytokeratin 8 and the other cell line showed strong positive against smooth muscle actin and cytokeratin 8. Additional characterization would be possible by investigator's needs and the cell lines may be useful for in vivo and in vitro studies of canine mammary tumor and adjuvant therapies.

• Korean Journal of Plant Tissue Culture
• /
• v.26 no.4
• /
• pp.281-287
• /
• 1999

Codonopsis lanceolata ("Deoduck" in Korea) is a perennial herb, and belongs to family, Campanulaceae. Its taproot is used a good source of a wild vegetable as well as an herbaceous medicine. In this study, to develop a bialaphos-resistant transgenic Codonopsis, seed germination mechanism and somatic embryogenesis of the plant were investigated, and Agrobacterium-mediated transformation with bar gene encoding phosphinothricin acetyltransferase (PAT) was performed. Attempt were made to regenerate plant from cells via somatic embryogenesis. When the cotyledons, nodes and leaf disks were cultured on MS medium containing 2,4-D and zeatin, embryogenic calli were induced. Upon transferring the somatic embryos to N6 solid medium without plant growth regulators, they developed into plantlets under continuous illumination. All plants were dead on MS basal medium containing 10 mg/L phosphinothricin (PPT) and Basta, respectively. The explants did not produce calli in the medium containing 200 mg/L kanamycin. The explants were cocultured with Agrobacterium tumefaciens for 2 days, and transformants were selected in MS basal medium containing 1.0 mg/L 2,4-D, 100 mg/L kanamycin and 500 mg/L carbenicillin. After the selection, embryogenic calli were induced and then somatic embryos were produced by subsequent subculturing. The somatic embryos were germiated on N6 basal medium containing 200 mg/L kanamycin and 500 mg/L carbenicillin. PCR analysis showed that nptII and bar genes were introduced in the Deoduck transformants. After the confirmation of bar gene expression in RNA and protein level, the transgenic Deoduck will be used to study the genetics of filial generation with the herbicide control gene, bar.gene, bar.

• Korean Journal of Plant Tissue Culture
• /
• v.26 no.4
• /
• pp.251-257
• /
• 1999

Adventitious buds were produced from the cultures of mature zygotic embryos of Larix leptolepis with the highest frequency of 91.7% in SH medium containing 1.0 mg/L zeatin. The most effective cytokinin combination for inducing adventitious buds was 1.0 mg/L zeatin + 1.0 mg/L thidiazuron (40.3%). The highest mean number of adventitious buds induced in 1.0 mg/L zeatin + 1.0 mg/L 2iP or 1.0 mg/L zeatin + 1.0 mg/L kinetin combined treatments. Elongation of the adventitious buds occurred the best on half strength LM salts medium, on which the buds elongated upto 27 mm. Also, the supplement of activated charcoal in medium suppressed the elongation of the adventitious buds. The highest frequency (23.3%) of rooting from elongated shoots was obtained on the medium containing 5.0 mg/L IBA and 0.2 mg/L NAA. The highest number (3.5) of roots was induced on the medium containing 5.0 mg/L IBA alone.

• Journal of Plant Biotechnology
• /
• v.32 no.3
• /
• pp.181-186
• /
• 2005

This work was conducted to evaluate the effects of rooting on tissue cultured M.9 (Malus domestica Bork. cv, tcM.9) after layering in field. We investigated an appearance period of first root in shoot, rooting ratio, contents of indole-3-acetic acid (IAA), abscisic acid (ABA), inorganic matters, sugars, and lignin in rooting areas of stems by layering. First root in shoot of tcM.9 and natural M.9 appeared 25 and 30 days after layering (DAL), respectively. Rooting ratio was much higher in tcM.9 than in natural M.9. The content of IAA was higher in tcM.9 than in natural M.9 before layering, but it was reversed at 20 and 30 DAL. In contrast, the content of ABA was much higher in natural M.9 than in tcM.9 in case of both before and 10 and 20 DAL. The contents of N, B, Mn, and Zn were significantly higher in tcM.9 than in natural M.9 both before and 10 and 20 DAL. The contents of sugars in tcM.9 had the similar pattern of the contents of inorganic materials. There were statistically significant differences in the contents of sucrose and glucose at 30 DAL as well as the content of maltose at 20 and 30 DAL. The content of lignin was significantly higher in tcM.9 than in natural M.9 before layering and 10 and 30 DAL while there was no difference 20 DAL. Therefore, improvement of rooting ability in the tissue cultured root stock M.9 might be due to the changes of inorganic matters or lignin rather than that of sugars and hormones.

• Journal of Plant Biotechnology
• /
• v.29 no.2
• /
• pp.135-138
• /
• 2002

Cotyledonary explants from immature zygotic embryos of each 85 recombinant inbred lines (RILs) were cultured on medium containing MS salts, B5 vitamins, 40 mg$^{-1}$ 2,4-dichlorophenoxyacetic acid and 30 g$^{-1}$ sucrose. Frequency of somatic embryo formation on cotyledonary explants showed in thirty-six lines(＜10%), in thirty-seven lines (11~49%), in nine lines (50~89%), and in three lines(>90%), respectively, The highest frequency (up to 90%) and number (6.36 per cotyledon) of somatic embryos were obtained from lines of KM1010, KM1032 and KM1064. Primary somatic embryos produced from three lines produced numerous secondary somatic embryos on the surfaces, which were subcultured for over one year. Upon transfer to maturation and conversion medium (Komatsuda, 1992), somatic embryos converted to plantlets at a frequency of approximately 25%.

• Korean Journal of Veterinary Research
• /
• v.37 no.3
• /
• pp.647-659
• /
• 1997

To overcome the difficulties of collecting and culture of primary cell from genital tract on embryonic development, the present study was carried out to investigate the critical effect of cell lines, such as BRL and Vero cell and its conditioned medium on the development of early Korean native cattle embryos in vitro. Oocytes collected from slaughterhouse ovaries were matured in TCM199 containing FSH, estradiol-$17{\beta}$ and FBS with granulosa cell monolayer for 24 hours and then fertilized in vitro using frozen-thawed, heparin-treated spermatozoa in TALP for 30 hours. And then early embryos (1-2cell) were cultured in TCM199 containing 10% FBS with BOEC, Granulosa, BRL, Vera cell monolayers and conditioned medium for 2~3 days. Development to morulae and blastocysts were recorded, also examined the number of blastomeres presented a valuable parameter for the evaluation of embryonic development. The early cleavage rates of in vitro fertilized embryos co-cultured, there was no differences between primary cell and cell lines(p<0.05). The rate of development to the later stage, coculture of BRL cell was significantly higher than that of the primary cell(p<0.05). The rates of development to morula and blastocyst were significantly higher in vero cell than BRL, Granulosa, Oviduct epithelial cell conditioned medium. In the result of effect of serum on development of early bovine embryos, the use of media containing serum were significantly higher than the use of not containing one on development of early and later stage of embryos. The result of number of blastomeres in blastocysts, there is no differences between primary cell and cell lines. The blastocysts from coculture were higher than from conditioned medium in blastomere cells. In summary, these experments have proved that the culture system in TCM199 with BRL, Vero cell monolayers is effective on in vitro development of early bovine embryos, In addition, it is effective to development of bovine embryos that containing serum in conditioned medium, or in co-culture rather than in conditioned medium alone. The use of cell lines opponent to primary cells is effective in bovine embryo culture.

• Korean Journal of Food Science and Technology
• /
• v.48 no.6
• /
• pp.560-564
• /
• 2016

The objective of this study was to investigate the anti-Bacillus cereus activity of actinonin. Actinonin inhibited the growth of B. cereus in a dose dependent manner. The growth-inhibitory activity of actinonin was evaluated using a broth micro-dilution method, and minimum inhibitory concentration (MIC) and agar disk diffusion tests. B. cereus showed high susceptibility to actinonin in a concentration-dependent manner and MIC was determined to be $0.192{\mu}g/mL$. Additionally, 1 and 2 mM actinonin induced formation of B. cereus inhibition zones. In addition, as compared to B. cereus alone, B. cereus added with $10{\mu}M$ actinonin showed a lower level of cytotoxicity in HeLa cells in vitro. Thus, this study revealed that actinonin could be a potential source of a natural antimicrobial agent or a pharmaceutical component against B. cereus.

• Korean Journal of Plant Tissue Culture
• /
• v.26 no.3
• /
• pp.183-187
• /
• 1999

To establish an efficient screening system for new herbicides using plant cultured cells, responses of tobacco photomixotrophic cultured (PH) cells to various herbicides with different modes of action were surveyed by measuring the cell growth and ion conductivity in medium. The cells were cultured in Murashige and Skoog (MS) medium containing 0.7mg/L 2,4-D, 0.3mg/L kinetin and 30 g/L sucrose at $25^{\circ}C$ in the light (100 rpm). Chemicals were treated to suspension cultures of tobacco PH cells at the time of subculture. The cell growth and ion conductivity in the medium were investigated on 12 days after chemical treatment. The ion conductivity assay gave well correlated results to the cell growth inhibition data. The responses of tobacco PM cells were dependent on the modes of action of chemicals tested. Atrazine, an inhibitor of photosynthetic electron transport (PET), strongly inhibited both the cell membrane and cell growth ($IC_{50}$/, about 1 $\mu$M). Butachlor (an inhibitor of cell division), glufosinate (an inhibitor of amino acid biosynthesis), and fluridone (an inhibitor of carotenoid biosynthesis) showed a dose-dependent inhibition. However, Quinclorac, a herbicide with an auxin activity, did not affect the cell growth and ion leakage. These results suggested that tobacco PM cells is suitable materials for the simple screening of new herbicides such as PET, amino acid biosynthesis, ceil division inhibitors by measuring the cell growth and ion conductivity.