• 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 Plant Resources
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• v.22 no.5
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• pp.461-466
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• 2009

This study was carried out to evaluate the effects of yam (Dioscorea batatas Dence) extracts on the cell viability, growth and nucleus-DNA damage of tobacco cells which were exposed to $\gamma$-radiation stress. The viability and growth of tobacco cells exposed to 20 Gy of radiation stress were effectively recovered by pretreatment of 10 mg/L ethylacetate (EtOAc) yam extract. Pretreatment of EtOAc extract showed 20% higher cell viability and fresh weight growth than that of cells without pretreatment in 20 Gy radiation treated tobacco cells. Nucleus-DNA damage was measured as the ratio of tail length (T) to head length (H) in individual comet image isolated from tobacco cells. The T/H ratio of control-cells and treated-cells at 20 Gy were 1.05 and 1.68, and % head DNA of those cell were 86.7 and 71.3%, respectively, suggesting that nuclei of tobacco cells were severely damaged in the integrity of DNA by the treatment of $\gamma$-radiation. However, pretreatment of MeOH, EtOAc and n-BuOH extracts decreased radiation induced DNA-damage in the tobacco cells, showing T/H ratio of 1.37, 1.01 and 1.10 and % head DNA of 81.5, 87.6 and 88.7%, respectively.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.65-68
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• 2000

To understand the antioxidative mechanism in plant cell cultures, we investigated the levels of antioxidant enzymes and low molecular antioxidants in 100 cell lines derived from different plant species. SOD and POD activities in plant cell lines were significantly higher than intact plants. The cell lines from sweet potato (Ipomoea batatas) and cassava (Manihot esculeanta) showed the highest POD and SOD activities, respectively, suggesting that the cell cultures of sweet potato and cassava are good biomaterials for the mass production and molecular study of antioxidant enzymes. The average ascorbate content in plant cell lines was several hundred times lower than intact plants, whereas the glutathione content was 2-3 times higher than plants. Interestingly, the ratio of reduced and oxidized ascorbate and glutathione was different from plant species. In conclusion, the results strongly suggest that plant cell cultures are good biomaterials for the study of antioxidative mechanism and the production of useful components including antioxidants.

• Journal of Plant Biology
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• v.35 no.3
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• pp.283-305
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• 1992

Phytoliths (plant stones) mean all types of mineral deposition formed in or between plant cells. However, most of the researches on the phytoliths so far have been focused on the opaline silica bodies (silicified phytoliths) formed by grasses. Therefore, the phytolith is usually refered to opaline silica body in a narrow sense. Phytoliths are very useful in grass classification, and their usefulness as microfossils is also proved in several other fields, including soil science, paleoecology, and archaeology. Recently attention has been paid to the possibility that they might function as carcinogen. The purpose of this review is to present an overview of the nature and analysis of phytoliths and their applications in botany as well as other fields of sciencess.encess.

• Korean Journal of Plant Tissue Culture
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• v.21 no.3
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• pp.151-156
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• 1994

Acifluorfen-tolerant cell lines of S, ptycanthum were isolated by stepwise selection using suspension culture. Growth of unselected line was completely inhibited at $0.5\;\mu\textrm{M}$, while some selected lines grew at $8\;\mu\textrm{M}$ acifluorfen. After subculturing on acifluorfen-free medium for 4 passages, six of the eleven cell lines screened and maintained their tolerance to $2\;\mu\textrm{M}$ acifluorfen. The regeneration capacity of selected cell lines in Solanum ptycanthum differed depending on the tell line. The acifluorfen tolerance of the somarclones regenerated from acifluorfen-tolerant cell lines differed depending on the somarclone. When plants were heated with $16\;\mu\textrm{M}$ acifluorfen, unselected control plane had over 75% phytotoxicity Many selected cell lines had less phytotoxicity than the seed-grown control plants. Tolerance to acifluorfen was inherited to the self-pollinated progenies. The inheritance patterns differed depending on the clone. Acifluorfen tolerance was inherited as a semidominant trait. Other segregation patterns were also observed. acifluorfen tolerance was recessive and acifluorfen sensitivity was dominant.

• Journal of Plant Biology
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• v.34 no.2
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• pp.137-144
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• 1991

기주식물 (토끼풀, Trifolium repens L.)에 기생하는 실새삼(Cuscuta australis R. Brown)의 흡기내 목부의 개체발생 과정을 광학현미경으로 조사하였다. 흡기의 목부 분화를 암시하는 최초의 해부학적 특징이, 흡기 자체내에서가 아니라, 그 흡기가 형성되어 있는 실새삼 줄기에서 나타났다. 즉 실새삼 줄기의 중심주의 유관속 내부 및 유관속 사이에서 세포분열 활성이 관찰되었다. 이 분열로부터 유도된 세포들은 짙게 염색된 세포질과 뚜렷한 핵을 갖고 있었다. 흡기가 기주조직에 침입하여 생장함에 따라, 실새삼 줄기의 중심주에서 시작된 세포분열 활성은 유관속 사이를 거쳐서 흡기의 기부를 향하여 구정적으로 확장되었다. 이와 동시에, 실새삼 줄기의 목부에 인접해 있던, 짙은 세포질 밀도를 갖는 세포들이 목부요소로 분화하기 시작하였다. 결국, 이미 형성되었던 짙게 염색된 세포들을 따라서 흡기의 목부는 구정적으로 분화하였다. 실새삼 줄기의 중심주에서 일어나는 유조직 세포들의 분열활성 및 이로부터 흡기의 목부 분화를 구정적으로 유도할 수 있는 가능성에 대하여 논의하였다.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.634-637
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• 2000

The productivity of natural flavors in alfalfa suspension cultures is low partially due to their low solubility. Thus, by formation inclusion complex of cyclodextrin(CD) with flavor compounds enhancement of the productivity of flavor was attempted in this research. we observed that CD formed inclusion complex with flavor compounds by GC/MS analysis. Also, there was indication that CD played a role as an elicitor in alfalfa suspension cultures.

• The Microorganisms and Industry
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• v.20 no.2
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• pp.33-40
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• 1994

미생물에 대한 유전자 재조합법 등의 개발로 동물세포에서만 합성되던 단백질들을 미생물을 통하여 생산하는 기술이 확립되어 있으나, 동물 세포내에서만 정확하게 실행되어지는 단백질 분자의 folding과 post-translational modification 등이 미생물에서는 불완전하게 이루어져 활성을 잃게 되는 단점이 있고, pyrogen과 같이 미생물로부터 유래한 endotoxin이 생산물에 섞여 있을수도 있으며, 미생물로부터 생산되는 각종 단백질로부터 원하는 유용 단백질을 분리하기 어려운것 등, 현실적으로 많은 어려움을 가지고 있기 때문에 미생물을 이용하기보다 동물 세포 배양을 통하여 위와 같은 제재들을 생산하려 하고 있다. 유전자 재조합 기술은, 현재 미생물뿐만 아니라, 동,식물 세포에 대하여도 적용되어 있어서 각종 유용생산물을 동,식물세포의 유전자 조작을 통해 얻을 수 있는 단계에 와 있으며, 이는 유전자 치료(gene therapy)와 같은 의료분야에까지 확장될 수 있게 되었다. 표 2에서는 동물 세포를 배양할 때와 미생물을 이용할 때의 각각의 특징을 보여주고 있다.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.104-108
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• 1990

The chromosomal DNA of Agrobacterium tumefaciens contains the genes required for bacterial attachment to plant cell which is an essential atage in crown gall tumorigenesis by Ti-plasmid. In order to clone the genes, Agrobacterium tumefaciens strain A5512 was mutagenized by transposon Tn5 and two Agrobacterium tumefaciens mutants which are attachment-defective and nontumorigenic were isolated. From one of the two mutants, a chromosomal virulence region which was required for attachment to the plant cells was cloned.

• KSBB Journal
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• v.16 no.4
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• pp.376-380
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• 2001

The human granulocyte-macrophage colony-stimulating factor (hGM-CSF) was produced from cell suspension culture of transgenic tobacco which was transformed by using Agrobacterium harboring the hGM-CSF gene. To improve the production of hGM-CSF in batch culture system, the effects of initial sucrose concentration and inoculum size were investigated. The results show that the hGM-CSF production was not affected by small inoculum size in medium containing either low or high concentration of sucrose. However, the production of hGM-CSF was increased under increasing of the inoculum sizes and sucrose concentration. Under the combination of inoculum and sucrose concentration, the maximum hGM-CSF production of 720 $\mu$g/L was obtained at 90 g/L of initial sucrose concentration and 110 g/L of inoculum size.