Tae-Geum Kim

Chonbuk National University, Tsiuentcheou, North Jeolla, South Korea

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Publications (60)104.88 Total impact

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    ABSTRACT: Dengue is a disease caused by dengue virus and represents the most important arthropod-borne viral disease in humans. Dengue virus enters host cells via binding of envelope glycoprotein (E) to a receptor. In this study, plant expression vectors containing native and synthetic glycoprotein E genes (sE) modified based on plant-optimized codon usage and fused with an ER retention signal were constructed under control of the rice amylase 3D promoter expression system. Plant expression vectors were introduced into rice callus (Oryza sativa L. cv. Dongin) via particle bombardment-mediated transformation. The integration and expression of target genes were confirmed in the transgenic callus by genomic DNA PCR and Northern blot analyses, respectively. The plant-codon optimized sE gene with an ER retention signal showed high protein production levels based on Western blot analysis of approximately 18.5 ug/g dried calli weight by immunoblot-based densitometric analysis. These results suggest that the plant-codon optimized sE gene with an ER retention signal was highly produced in the transgenic rice callus.
    Molecular Biotechnology 07/2014; · 2.26 Impact Factor
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    ABSTRACT: We report a feasibility study for expressing the LTB protein (Escherichia coli heat-labile enterotoxin B subunit) via Agrobacterium-mediated transformation of tomato (Solanum lycopersicum L.). We produced five regenerated plants obtained on the selection medium supplemented with an antibiotic. Stable integrations of the LTB gene into the genome of these plants were confirmed by Southern blot hybridization. Western blot analysis showed that only two of the five T0 transgenic tomato plants expressed the pentameric LTB protein in the fruits. An enzyme-linked immunosorbent assay indicated that these two plants synthesized the LTB protein bound specifically to GM1 ganglioside, suggesting that the LTB subunits formed active pentamers. The LTB protein produced in tomatoes can be a potential candidate for inexpensive, safe, and effective plant-based vaccines.
    Czech Journal of Genetics and Plant Breeding. 02/2014; 50(1):26-31.
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    ABSTRACT: Vascular endothelial growth factors (VEGFs) are secreted by tumor cells and other cells exposed to hypoxia, and play a critical role in the development and differentiation of the vascular system. In this study, we investigated the production of functional recombinant human VEGF165 (rhVEGF165) in transgenic rice cell suspension culture. Complementary DNA was synthesized from human leukemia HL60 cells and cloned into expression vectors under the control of the rice α-amylase 3D (RAmy3D) promoter. The rice seed (Oryza sativa L. cv. Dongjin) was transformed with this recombinant vector by the Agrobacterium mediated method and the integration of the target gene into the plant genome was confirmed by genomic PCR. The expression of rhVEGF165 in the rice cells was determined by Northern blot and Western blot analyses. The accumulated rhVEGF165 protein in the culture medium was 19 mg/L after 18days of culturing in a sugar-free medium. The rhVEGF165 was purified using aheparin HP column and its biological activity was tested on human umbilical vein endothelial cells (HUVECs). The purified rhVEGF165 significantly increased the proliferative activity of the HUVECs. Therefore, it was demonstrated that functional rhVEGF165 could be produced using transgenic rice suspension culture vector under the control of the RAmy3D promoter.
    Enzyme and Microbial Technology 01/2014; · 2.97 Impact Factor
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    ABSTRACT: In this work, the characterizations of the LTB (Escherichia coli heat-labile toxin B subunit) transgenic watercresses through Agrobacterium tumefaciens-mediated transformation (A1 and A3-A5) and by using biolistic method (B1 and B4) were investigated. Generally, their growth is not remarkably different from the wild-type. Their physiological and biochemical characteristics are relatively different in which plant A1 has highest values such as pigment (0.92 mg g-1), photosynthetic rate (23.39 mgCO2 [dm2]-1 h-1), dry matter (7.42%), vitamin C (0.34 mg g-1), calcium (0.83 mg g-1), and potassium (2.47 mg g-1). The dry matter and calcium of all the transgenic watercresses and the wild-type are the same content. Southern blot hybridization showed the transgenic plants contain 1-2 copies in the genome. LTB protein strongly expresses in all the transgenic plants with contents from 1.16 to 1.46% of total soluble protein. The GM1-ELISA binding assay indicated that plant-derived LTB protein bound to GM1-ganglioside receptors.
    Journal of Plant Biochemistry and Biotechnology 01/2013; · 0.41 Impact Factor
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    ABSTRACT: The spread of dengue (DEN) virus is becoming a major concern due to the possibility of primary infection with one of the four dengue serotypes (DEN 1-4) and secondary infection with other heterotypes, which can further aggravate clinical manifestations. A gene encoding consensus envelope protein domain III (cEDIII) of dengue virus with neutralizing activity against four dengue virus serotypes was fused to M cell-targeting peptide ligand (Co1) to increase its mucosal immunogenicity and was introduced into rice calli under the control of the inducible rice amylase 3D promoter expression system. The integration and expression of scEDIII-Co1 fusion gene in transgenic rice calli were confirmed by genomic DNA PCR amplification, Northern and Western blot analyses, respectively. The deliveries of cEDIII-Co1 fusion proteins into mucosal immune inductive site (including M cells) were confirmed by in vitro and in vivo antigen uptake assays. These results showed that plant-produced M cell-targeting peptide ligand, Co1, fusion antigen proteins have the potential to be targeted to the mucosal immune system for improvement of immune responses.
    Molecular Biotechnology 12/2012; · 2.26 Impact Factor
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    ABSTRACT: To increase immune responses of plant-based vaccines in intestine mucosal immune systems, a synthetic neutralizing epitope (sCOE) gene of porcine epidemic diarrhea virus (PEDV) was fused with M cell-targeting ligand (Co1) and introduced into a plant expression vector under the control of rice amylase 3D promoter. The sCOE-Co1 fusion gene was introduced into rice calli via the particle bombardment-mediated transformation method. The stable integration and transcriptional expression of the sCOE-Co1 fusion gene was confirmed by genomic DNA PCR amplification and Northern blot analysis, respectively. The expression of the COE-Co1 fusion protein was confirmed by immunoblot analysis. The highest expression level of the COE-Co1 fusion protein reached 0.083 % of the total soluble protein according to quantitative densitometry of Western blot analysis. Mice immunized with transgenic rice calli protein extracts induced significant serum IgG and fecal IgA antibody levels against purified bacterial COE. The systemic and mucosal immune responses were confirmed by measuring COE-specific IgG and IgA antibody-secreting cells in the lymphocytes extracted from the spleen and COE-specific IgA antibody-secreting cells in the Peyer's patches from immunized mice. These results indicated that oral immunization of plant-produced COE-Co1 fusion protein could elicit efficient systemic and mucosal immune responses against the COE antigen. Key message Neutralizing epitope from porcine epidemic diarrhea virus-M cell targeting ligand fusion protein was produced in transgenic rice calli and elicited systemic and mucosal immune responses by oral administration in mice.
    Plant Cell Reports 06/2012; 31(10):1933-42. · 2.94 Impact Factor
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    ABSTRACT: In this study, three LTB (Escherichia coli heat-labile toxin B subunit) transgenic tomato lines (#1-3) were grown in the pot to characterize their growth and development, and evaluate fruit and LTB subunit productivity. Generally, the growth and development of transgenic tomato lines are not significantly different with non-transgenic tomato cultivar, “311” (commercial cultivar as reference). All of them took 120 days to final harvest, and number of fruit is near equivalent. However, fruit quality characteristics are relatively different and line #3 has highest values of dry matter (6.02%), reducing sugar (2.51%) and degree Brix (6.40%). The vitamin C and acidity of all transgenic lines and the control are the same content. LTB subunit only expressed in two lines #1 and #3 with contents of 1.04% and 1.19% of total soluble protein, respectively.
    Annals of Biological Research. 05/2012; 3(5):2070-2073.
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    ABSTRACT: The cholera toxin B subunit (CTB), a nontoxic molecule with potent biological properties, is a powerful mucosal and parenteral adjuvant that induces a strong immune response against co-administered or coupled anti- gens. A gene encoding CTB, which was modified based on the optimized codon usage in the plant, was synthesized and fused to the endoplasmic reticulum retention signal KDEL to enhance its expression level in plants. The syn- thetic CTB (sCTB) gene was introduced into a plant ex- pression vector adjacent to the CaMV 35S promoter, and was transformed into tomato using an Agrobacterium- mediated transformation method. The integration of the sCTB gene into the genomic DNA of transgenic plants was confirmed by genomic DNA PCR amplification. The syn- thesis and assembly of CTB protein in transgenic plants was demonstrated through immunoblot analysis and G - ELISA. The highest amount of CTB protein produced in transgenic tomatoes was approximately 0.9% of total soluble fruit protein which was 10-fold greater than the previously 0.081%. G -ELISA indicated that plant-synthesized CTB protein bound specifically to G -gangliosides, suggesting that the CTB subunits formed active pentamers.
    Biotechnology and Bioprocess Engineering 06/2011; 16:576-580. · 1.28 Impact Factor
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    ABSTRACT: A gene encoding the B subunit of the enterotoxigenic Escherichia coli heat-labile enterotoxin (LTB) was adapted to the optimized plant coding sequence, and fused to the endoplasmic reticulum retention signal SEKDEL in order to enhance its expression level and protein assembly in plants. The synthetic LTB (sLTB) gene was placed into a plant expression vector under the control of the CaMV 35S promoter, and subsequently introduced into the watercress (Nasturtium officinale L.) plant by the Agrobacterium-mediated transformation method. The integration of the sLTB gene into the genomic DNA of transgenic plants was confirmed by genomic DNA PCR amplification. The assembly of plant-produced LTB protein was detected by western blot analysis. The highest amount of LTB protein produced in transgenic watercress leaf tissue was approximately 1.3% of the total soluble plant protein. GM1-ganglioside enzyme-linked immunosorbent assay indicated that plant-synthesized LTB protein bound specifically to GM1-ganglioside, which is the receptor for biologically active LTB on the cell surface, suggesting that the plant-synthesized LTB subunits formed biologically active pentamers.
    Plant Cell Tissue and Organ Culture 04/2011; 105(1):39-45. · 2.61 Impact Factor
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    ABSTRACT: FimA of Porphyromonas gingivalis, a major pathogen in periodontitis, is known to be closely related to the virulence of these bacteria and has been suggested as a candidate for development of a vaccine against periodontal disease. In order to develop a passive immunization method for inhibiting the establishment of periodontal disease, B hybridoma clones 123-123-10 and 256-265-9, which produce monoclonal antibodies (Mabs) specific to purified fimbriae, were established. Both mAbs reacted with the conformational epitopes displayed by partially dissociated oligomers of FimA, but not with the 43 kDa FimA monomer. Gene sequence analyses of full-length cDNAs encoding heavy and light chain immunoglobulins enabled classification of the genes of mAb 123-123-10 as members of the mVh II (A) and mVκ I subgroups, and those of mAb 256-265-9 as members of the mVh III (D) and mVκ I subgroups. More importantly, 50 ng/mL of antibodies purified from the culture supernatant of antibody gene-transfected CHO cells inhibited, by approximately 50%, binding of P. gingivalis to saliva-coated hydroxyapatite bead surfaces. It is expected that these mAbs could be used as a basis for passive immunization against P. gingivalis-mediated periodontitis.
    Microbiology and Immunology 01/2011; 55(3):199-210. · 1.55 Impact Factor
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    ABSTRACT: The cholera toxin B subunit (CTB), a nontoxic molecule with potent biological properties, is a powerful mucosal and parenteral adjuvant that induces a strong immune response against co-administered or coupled antigens. A gene encoding CTB, which was modified based on the optimized codon usage in the plant, was synthesized and fused to the endoplasmic reticulum retention signal KDEL to enhance its expression level in plants. The synthetic CTB (sCTB) gene was introduced into a plant expression vector adjacent to the CaMV 35S promoter, and was transformed into tomato using an Agrobacterium-mediated transformation method. The integration of the sCTB gene into the genomic DNA of transgenic plants was confirmed by genomic DNA PCR amplification. The synthesis and assembly of CTB protein in transgenic plants was demonstrated through immunoblot analysis and GM1-ELISA. The highest amount of CTB protein produced in transgenic tomatoes was approximately 0.9% of total soluble fruit protein which was 10-fold greater than the previously 0.081%. GM1-ELISA indicated that plant-synthesized CTB protein bound specifically to GM1-gangliosides, suggesting that the CTB subunits formed active pentamers.
    Biotechnology and Bioprocess Engineering. 01/2011; 16(3):576-580.
  • Tae-Geum Kim, Mi-Young Kim, Moon-Sik Yang
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    ABSTRACT: Envelope glycoprotein E of the dengue virus, which plays a crucial role in its entry into host cells, has an immunogenic domain III (EIII, amino acids 297-394), which is capable of inducing neutralizing antibodies. However, mice immunized with EIII protein without adjuvant elicited low immune responses. To improve low immune responses, a DNA fragment, consisting of cholera toxin B subunit and EIII gene (CTB-EIII), was constructed and introduced into tobacco plant cells (Nicotiana tabacum L. cv. MD609) by Agrobacterium tumefaciens-mediated transformation methods. The integration and transcription of CTB-EIII fusion gene were confirmed in transgenic plants by genomic DNA PCR amplification and Northern blot analysis, respectively. The results of immunoblot analysis with anti-CTB and anti-dengue virus antibodies showed the expression of the CTB-EIII fusion protein in transgenic plant extracts. Based on the G(M1)-ELISA results, the CTB-EIII protein expressed in plants showed the biological activity for intestinal epithelial cell membrane glycolipid receptor, G(M1)-ganglioside, and its expression level was up to about 0.019% of total soluble protein in transgenic plant leaf tissues. The feasibility of using a plant-produced CTB-EIII fusion protein to generate immunogenicity against domain III will be tested in future animal experiments.
    Protein Expression and Purification 12/2010; 74(2):236-41. · 1.43 Impact Factor
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    ABSTRACT: Transgenic plants have been used as a safe and economic expression system for the production of edible vaccines. A synthetic cholera toxin B subunit gene (CTB) was fused with a synthetic neutralizing epitope gene of the porcine epidemic diarrhea virus (sCTB-sCOE), and the sCTB-sCOE fusion gene was introduced into a plant expression vector under the control of the ubiquitin promoter. This plant expression vector was transformed into lettuce (Lactuca sativa L.) using the Agrobacterium-mediated transformation method. Stable integration and transcriptional expression of the sCTB-sCOE fusion gene was confirmed using genomic DNA PCR analysis and northern blot analysis, respectively. The results of western blot analysis with anti-cholera toxin and anti-COE antibody showed the synthesis and assembly of CTB-COE fusion protein into oligomeric structures with pentameric sizing. The biological activity of CTB-COE fusion protein to its receptor, G(M1)-ganglioside, in transgenic plants was confirmed via G(M1)-ELISA with anti-cholera toxin and anti-COE antibody. Based on G(M1)-ELISA, the expression level of CTB-COE fusion proteins reached 0.0065% of the total soluble protein in transgenic lettuce leaf tissues. Transgenic lettuce successfully expressing CTB-COE fusion protein will be tested to induce efficient immune responses against porcine epidemic diarrhea virus infection by administration with raw material.
    Molecular Biotechnology 12/2010; 48(3):201-9. · 2.26 Impact Factor
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    ABSTRACT: Growing interest in the beneficial effects of antioxidants has inspired the synthesis of new phenolic acid phenethyl ureas (PAPUs) with enhanced antioxidant potential. We have previously shown the capacity of one PAPU compound, (E)-1-(3,4-dihydroxyphenethyl)-3-styrylurea (PAPU1), to induce caspase-dependent apoptosis in melanoma cells. In the present study, we examined the anti-proliferative effects of PAPU compounds on MCF-7 human breast cancer cells and determined the molecular mechanisms involved. Treatment with PAPU compounds inhibited predominantly proliferation in these cells, where the PAPU1 was the most efficient form. Flow cytometric analysis showed that PAPU1 blocked cell cycle progression in the G(0)/G(1) phase, and reduced the proportion of cells in G(2)/M phase. This was related to the inhibition of cell cycle regulatory factors, including cyclin D/E and cyclin-dependent kinase (CDK) 2/4, through induction of p21(Cip1). PAPU1 also induced the mitochondrial-mediated and caspase-dependent apoptosis in MCF-7 cells. This was evidenced by cellular changes in the levels of Bcl-2 and Bax, loss of the mitochondrial membrane potential, release of cytochrome c into the cytosol, and caspase-9 activation. Collectively, our results suggest that G(1) cell cycle regulatory proteins and mitochondrial pathways are the crucial targets of PAPU1 in the chemoprevention of breast cancer cells.
    Molecules and Cells 10/2010; 30(4):303-10. · 2.21 Impact Factor
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    ABSTRACT: The B subunit of Escherichia coli heat-labile enterotoxin (LTB), a non-toxic molecule with potent biological properties, is a powerful mucosal and parenteral adjuvant that induces a strong immune response against co-administered or coupled antigens. We synthesized a gene encoding the LTB adapted to the optimized coding sequences in plants and fused to the endoplasmic reticulum retention signal SEKDEL to enhance its expression level and protein assembly in plants. The synthetic LTB gene was located into a plant expression vector under the control of CaMV 35S promoter and was introduced into Peperomia pellucida by biolistic transformation method. The integration of synthetic LTB gene into genomic DNA of transgenic plants was confirmed by genomic DNA PCR amplification method. The assembly of plant-produced LTB was detected by western blot analysis. The amount of LTB protein produced in transgenic P. pellucida leaves was approximately 0.75% of the total soluble plant protein. Enzyme-linked immunosorbent assay indicated that plant-synthesized LTB protein bound specifically to GM1-ganglioside, which is receptor for LTB on the cell surface, suggesting that the LTB subunits formed biological active pentamers.
    Protein Expression and Purification 02/2010; 72(1):82-6. · 1.43 Impact Factor
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    ABSTRACT: Actinobacillus pleuropneumoniae is a major etiological agent of swine pleuropneumonia, a highly contagious respiratory infection that causes severe economic losses in the swine production industry. ApxIIA, one of the virulence factors in A. pleuropneumoniae, is considered a candidate for the development of a vaccine against this bacterial infection. In this study, a fusion gene consisting of enterotoxigenic Escherichia coli heat-labile enterotoxin B subunit (LTB) and an ApxIIA fragment (amino acids 619–801) (ApxIIA619–801) was fused to the endoplasmic reticulum (ER) retention signal (SEKDEL) and introduced into a plant expression vector under the control of a ubiquitin promoter. The plant expression vector was transformed into tobacco Nicotiana tabacum L. cv. MD609 using an Agrobacterium-mediated transformation procedure. The integration and transcription of the LTB fusion gene were confirmed by genomic DNA PCR amplification and Northern blot analysis, respectively. The synthesis and assembly of LTB fusion protein were evidenced by Western blot analysis and the GM1-ganglioside enzyme-linked immunosorbent assay (GM1-ELISA). A quantitative ELISA used to measure the amount of LTB fusion protein produced in the transgenic plant revealed high levels of the fusion protein, up to 30μgg−1, in lyophilized leaf tissue. These results demonstrate the feasibility of using a transgenic plant to express the LTB-ApxIIA619–801 fusion protein as a first step towards producing plant-based edible vaccines to elicit immune responses against A. pleuropneumoniae via an oral mucosal delivery system. KeywordsEnterotoxigenic Escherichia coli heat-labile enterotoxin B subunit– Actinobacillus pleuropneumoniae –Plant-based edible vaccine–ApxIIA
    Plant Cell Tissue and Organ Culture 01/2010; 105(3):375-382. · 2.61 Impact Factor
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    ABSTRACT: Activator protein-1 can induce either cell survival or death, which is controlled by opposing effects of different Jun members. It is generally accepted that c-Jun is pro-apoptotic, but that JunD is anti-apoptotic in stress-exposed cells. Additionally, although there are reports suggesting that JunB plays a protective role, its role in stress-induced apoptosis remains unclear. Here, we investigated the role of JunB in H(2)O(2)-induced cell death using cells that over-expressed the protein or were transfected with si-JunB. Inhibition of JunB expression accelerated H(2)O(2)-mediated loss of mitochondrial membrane potential (MMP) and cytotoxicity. Conversely, over-expression of JunB protein led to significant inhibition of the MMP loss and cell death. The increase in JunB expression also attenuated nuclear relocation of apoptosis-inducing factor and mitochondrial Bcl-2 reduction that occurred following H(2)O(2) exposure. These results suggest that JunB can signal survival against oxidant-mediated cell death by suppressing mitochondrial stress. [BMB reports 2010; 43(1): 57-61].
    BMB reports 01/2010; 43(1):57-61. · 1.63 Impact Factor
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    ABSTRACT: Leaf explants of the Solanum hainanense plant, grown in vitro, were cultured in basal Murashige and Skoog (MS) media supplemented with 0.5 mg/L kinetin and 1 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) for callus initiation. For maintenance and proliferation, the callus was cultured on MS medium supplemented with 1 mg/L 6-benzylaminopurine (BAP) and 0.5 mg/L 2,4-D. The glycoalkaloid content in the callus was at its maximum after ten weeks of culture (188.65 mg/g), whereas that of the one-year-old control was 22.22 mg/g in the root and 5.99 mg/g in the stem. The glycoalkaloid extracted from the callus inhibited the activity of collagenase on collagen gel. High performance liquid chromatography (HPLC) analysis showed that biotransformation occurred when a callus was grown on medium supplemented with various carbon sources. These results suggest that callus of S. hainanense is a good material for production of glycoalkaloid.
    Journal of Plant Biotechnology. 01/2010; 37:96-101.
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    Eun-Mi Koh, Ju Kim, Jin-Yong Lee, Tae-Geum Kim
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    ABSTRACT: The FimA of Porphyromonas gingivalis is a crucial pathogenic component of the bacteria and has been implicated as a target for vaccine development against the periodontal diseases. In this study, the purified fimbriae (FimA subunit polymers) protein was used for immunization in their native form and B hybridoma clones producing antibodies specific to FimA were established. The monoclonal antibodies prepared from selected two clones, designated #123 (IgG2b/ kappa) and #265 (IgG1/kappa), displayed different patterns of binding activity against the cognate antigen. Both antibodies reacted with conformational epitopes expressed by partially dissociated oligomers, but not with monomer as elucidated by Western blot analysis. Ascites fluid containing the monoclonal antibodies showed the inhibitory activity against P. gingivalis to saliva-coated hydroxyapatite beads, an in vitro model for the pellicle-coated tooth surface. These results suggest that the monoclonal antibodies could be used as vaccine material against the periodontal diseases through passive immunization.
    Immune Network 10/2009; 9(5):203-7.
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    ABSTRACT: We developed a cell suspension culture system for zedoary (Curcuma zedoaria Roscoe), using 100 g fresh weight inoculum in a batch culture. The maximum cell biomass of 68.46 g/L fresh weight was obtained after 14 days of culture in a 10 L bioreactor with a pitch-blade impeller maintained at an agitation speed of 150 rpm and an aeration rate of 2.5 L/min. The accumulation of sesquiterpenes and polysaccharide in zedoary cells from 2 to 18 days was measured by HPLC and a phenol-sulfuric acid assay, respectively. The total polysaccharide concentration increased between 2 to 10 days of culture and reached a maximum value of 6.55%. HPLC revealed several eluted peaks of sesquiterpenes, which increased in amplitude from days 2 to 10. Furthermore, our results indicated that biotransformation occurred in the cell suspension, transforming certain sesquiterpenes into other types during culture.
    Biotechnology and Bioprocess Engineering 10/2009; 14(5):619-624. · 1.28 Impact Factor

Publication Stats

454 Citations
104.88 Total Impact Points

Institutions

  • 1999–2014
    • Chonbuk National University
      • Department of Molecular Biology
      Tsiuentcheou, North Jeolla, South Korea
  • 2010
    • Korea Basic Science Institute KBSI
      • Jeonju Center
      Seoul, Seoul, South Korea
  • 2008–2010
    • Hue University
      Nam Din, Nam Ðịnh, Vietnam
  • 2007–2008
    • Budapest University of Technology and Economics
      Budapeŝto, Budapest, Hungary
  • 2004–2006
    • Loma Linda University
      • Department of Medicine
      Loma Linda, CA, United States