Young-Seob Lee

National Institute of Horticultural and Herbal Sciences, Junten, South Jeolla, South Korea

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Publications (23)45.69 Total impact

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    ABSTRACT: OBJECTIVE: Cheongseoikki-tang (CIT, Korean), also called Qingshu Yiqi decoction () and Seisho-ekki-to (Japanese), is well known as an effective traditional combination of herbs for treating cardiovascular diseases. This study was to research its effects on bone marrow-derived mast cell (BMMC)-mediated allergy and inflammation mechanisms. METHODS: In this study, the biological effect of Cheongseoikki-tang ethanol extract (CITE) was evaluated, focusing on its effects on the production of allergic mediators by phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187)-stimulated BMMCs. These allergic mediators included interleukin-6 (IL-6), prostaglandin D2 (PGD2), leukotriene C4(LTC 4, and β-hexosaminidase (β-hex). RESULTS: Our data revealed that CITE inhibited the production of IL-6, PGD2, LTC4, and β-hex induced by PMA plus A23187 P<0.05). CONCLUSION: These findings indicate that CITE has the potential for use in the treatment of allergy.
    Chinese Journal of Integrative Medicine 03/2013; · 1.06 Impact Factor
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    ABSTRACT: Sophoraflavanone B (SPF-B), a known prenylated flavonoid, was isolated from the roots of Desmodium caudatum. The aim of this study was to determine the antimicrobial synergism of SPF-B combined with antibiotics against methicillin-resistant Staphylococcus aureus (MRSA). MRSA, a multidrug-resistant pathogen, causes both hospital- and community-acquired infections worldwide. The antimicrobial activity of SPF-B was assessed by the broth microdilution method, checkerboard dilution test, and time-kill curve assay. The MIC of SPF-B for 7 strains of S. aureus ranges from 15.6 to 31.25 μ g/mL determined. In the checkerboard method, the combinations of SPF-B with antibiotics had a synergistic effect; SPF-B markedly reduced the MICs of the β -lactam antibiotics: ampicillin (AMP) and oxacillin (OXI); aminoglycosides gentamicin (GET); quinolones ciprofloxacin (CIP) and norfloxacin (NOR) against MRSA. The time-kill curves assay showed that a combined SPF-B and selected antibiotics treatment reduced the bacterial counts below the lowest detectable limit after 24 h. These data suggest that the antibacterial activity of SPF-B against MRSA can be effectively increased through its combination with three groups of antibiotics ( β -lactams, aminoglycosides, and quinolones). Our research can be a valuable and significant source for the development of a new antibacterial drug with low MRSA resistance.
    Evidence-based Complementary and Alternative Medicine 01/2013; 2013:823794. · 1.72 Impact Factor
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    ABSTRACT: Tetrandrine (TET) is a bis-benzylisoquinoline alkaloid derived from the radix of Stephania tetrandra S. Moore. TET performs a wide spectrum of biological activities. The radix of S. tetrandrae has been used traditionally in Asia, including Korea, to treat congestive circulatory disorders and inflammatory diseases. The aim of this study was to examine the mechanism of antibacterial activity of tetrandrine against Staphylococcus aureus. The mechanism was investigated by studying the effects of TET in combination with detergent or membrane potential un-couplers. In addition, the direct involvement of peptidoglycan (PGN) was assessed in titration assays. TET activity against S. aureus was 125-250 μg/mL, and the minimum inhibitory concentration (MIC) of the two reference strains was 250 μg/mL. The OD(600) of each suspension treated with a combination of ethylenediaminetetraacetic acid (EDTA), tris(hydroxymethyl) aminomethane (TRIS), and Triton X-100 (TX) with TET (0.25×MIC) had been reduced from 43% to 96%. Additional structure-function studies on the antibacterialactivity of TET in combination with other agents may lead to the discovery of more effective antibacterial agents.
    Foodborne Pathogens and Disease 07/2012; 9(8):686-91. · 2.28 Impact Factor
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    ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) along with other resistant bacteria have become a significant social and clinical problem. Therefore, there is an urgent need to develop bioactive compounds from natural products as alternatives to the very few antibiotics that remain effective. Recently, the efflux mechanism has been identified as the main contributor to antibiotic resistance in bacteria. This study therefore aimed to evaluate tetrandrine (TET), an efflux pump inhibitor (EPI), as a potential antibiotic against MRSA. We investigated the antimicrobial activity of TET against 17 MRSA strains, of which 3 selected strains were studied in further detail using a time-kill assay. When these bacterial strains (1 × 10(6) colony-forming units (cfu)/ml) were incubated with TET in a time-kill assay, log-scale bactericidal activity was observed, which lasted for 24 hr. In addition, TET exhibits a synergistic effect when combined with the multi-drug resistance (MDR)-efflux pump substrate ethidium bromide (EtBr). Structure-function studies of the antibiotic activity of TET in combination with EtBr may lead to the discovery of more effective efflux pump inhibitors.
    The Journal of Toxicological Sciences 10/2011; 36(5):645-51. · 1.38 Impact Factor
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    ABSTRACT: Sinomenine is an alkaloid compound and a prominent anti-allergic agent found in the root of the climbing plant Sinomenium acutum. However, its effects on the bone marrow-derived mast cell (BMMC) mediated allergy and inflammation mechanism remain unknown. In this study, the biological effects of sinomenine were evaluated while focusing on its effects on the allergic mediator in PMA plus A23187-stimulated BMMCs. An investigation was also conducted to determine its effects on the production of several allergic mediators including interleukin-6 (IL-6), prostaglandin D(2) (PGD(2)), leukotriene C(4) (LTC(4)), β-Hexosaminidase (β-Hex), and cyclooxygenase-2 (COX-2) protein. The results revealed that sinomenine inhibited the PMA plus A23187-induced production of IL-6, PGD(2), LTC(4), β-Hex, and COX-2 protein. Taken together, these findings indicate that sinomenine has the potential for use in the treatment of allergy.
    Immunopharmacology and Immunotoxicology 11/2010; 33(2):266-70. · 1.36 Impact Factor
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    ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) is a substantial contributor to morbidity and mortality. In search of a natural products capable of inhibiting this multidrug resistant bacteria, we have investigated the antimicrobial activity of emodin (EM) isolated from Rheum palmatum L. (Polygonaceae) against 17 different strains of the bacterium. New antimicrobial activity was found using the paper disc diffusion method, agar dilution as well as checkerboard method. Against the 17 strains, the disc diffusion test was in the range of 18-30 mm, and the minimum inhibitory concentrations (MICs) of EM were in the range of 1.5-25 μg/mL. From those results we performed the checkerboard test to determine the synergism of EM in combination with ampicillin (AM) or oxacillin (OX) against all strains. The combined activity of EM and two antimicrobial agents (AM, OX) against all strains resulted in a fractional inhibitory concentrations index (FICI) ranging from 0.37-0.5 and from 0.37-0.75, respectively. The effect of EM with AM and OX was found to be synergistic or partially synergistic. We found that EM reduced the MICs of AM and OX. EM and in combination with AM or OX could lead to the development of new combination antibiotics against MRSA infection.
    Pharmaceutical Biology 10/2010; 48(11):1285-90. · 1.21 Impact Factor
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    ABSTRACT: For centuries, Corydalis Rhizoma has been used in Korean traditional medicine. Tetrahydropalmatine is an alkaloid compound and a prominent anti-inflammatory agent found in plants, including Corydalis yanhusuo. However, the therapeutic mechanisms of tetrahydropalmatine are still not well understood. To provide insight into the biological effects of tetrahydropalmatine, we examined its influence on lipopolysaccharide (LPS)-induced interleukin (IL)-8 production in the human monocytic cell line THP-1. In the present study, IL-8 production was measured using enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction, and mitogen-activated protein kinase (MAPK) activation, as determined by western blot analysis. Tetrahydropalmatine inhibited LPS-induced IL-8 production in a dose-dependent manner. Furthermore, tetrahydropalmatine inhibited extracellular signal-regulated kinase and p38 MAPK phosphorylation, which suggests that tetrahydropalmatine inhibits IL-8 secretion by blocking MAPK phosphorylation. Taken together, these findings may help elucidate the mechanism by which tetrahydropalmatine modulates THP-1 cell activation under inflammatory conditions.
    Journal of medicinal food 10/2010; 13(5):1125-32. · 1.39 Impact Factor
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    ABSTRACT: Platycodon grandiflorum (Campanulaceae) is used as traditional medicine in Asian countries. In Korean traditional medicine, Platycodon root has been widely used since ancient times as a traditional drug to treat cold, cough and asthma. However, its effects on bone marrow-derived mast cell (BMMC)-mediated allergy and inflammation mechanisms remain unknown. In this study, the biological effect of Platycodon root ethanol extract (PE) was evaluated in BMMC after induction of allergic mediators by phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187) stimulation. The effect of PE on the production of several allergic mediators, such as interleukin-6 (IL-6), prostaglandin D(2) (PGD(2)), leukotriene C(4) (LTC(4)), beta-Hexosaminidase (beta-Hex) and cyclooxygenase-2 (COX-2) protein, was investigated. The results demonstrate that PE inhibits PMA + A23187 induced production of IL-6, PGD(2), LTC(4), beta-Hexosaminidase and COX-2 protein. Taken together, these results indicate that PE has the potential for use in the treatment of allergy.
    International Journal of Molecular Sciences 01/2010; 11(7):2746-58. · 2.46 Impact Factor
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    ABSTRACT: To determine the anti-inflammatory and analgesic activities of methyl gallate (MG) isolated from Galla Rhois, MG was studied in vivo for its analgesic activities using the writhing response in mice. Anti-inflammatory activity of MG was evaluated for NO and IL-6 production in RAW 264.7 cells. MG inhibited LPS-induced NO and IL-6 production. Consistent with these observations, the protein and mRNA expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were inhibited by MG. Moreover, MG suppressed the phosphorylation of ERK1/2 in LPS-induced RAW 264.7 cells in a dose-dependent manner. Taken together, the results of this study indicate that MG has anti-inflammatory effects.
    The American Journal of Chinese Medicine 01/2010; 38(5):973-83. · 2.28 Impact Factor
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    ABSTRACT: Ecklonia cava is a brown alga (Laminariales, Phaeophyta) growing on the subtidal rocky shores of Korea. It has antioxidant, antidiarrhea, and anticoagulant effects. In this study, the antimicrobial activity of E. cava EtOH extract and its fractions (n-hexane, CH2Cl2, EtOAc, n-BuOH, and H2O) were investigated against methicillin-resistant Staphylococcus aureus and Salmonella spp. The E. cava EtOAc fraction showed good antibacterial activity against all bacteria. Eckol isolated from E. cava EtOAc fraction showed antimicrobial activity against all the tested strains. The minimum inhibitory concentration of eckol against S. aureus strains ranged from 125 to 250 microg/mL and 125 to 250 microg/mL for Salmonella strains. The fraction inhibitory concentration index of eckol in combination with ampicillin ranged from 0.31 to 0.5, indicating remarkable synergism against S. aureus. However, against Salmonella gallinarum ATCC 9184 and Salmonella typhimurium, it ranges from 0.75 to 1.0. The combinations of eckol + ampicillin exhibited improved inhibition of S. aureus and Salmonella with synergy or additive effect. We suggest that eckol ingredients of the E. cava against S. aureus and Salmonella have antibacterial activity.
    Foodborne Pathogens and Disease 12/2009; 7(4):435-41. · 2.28 Impact Factor
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    ABSTRACT: Punica granatum is commonly used in Korea as a traditional medicine for the treatment of pathogenic bacteria. In this study, we investigated the in vitro and in vivo antimicrobial activity of P. granatum peel EtOH extract (PGPE) against 16 strains of Salmonella. The minimal inhibitory concentrations of PGPE were in the range of 62.5-1000 x03BCg mL(-1). In addition, the in vivo antibacterial activity of the PGPE extract was examined in a S. typhimurium infection mouse model. Mice were initially infected with S. typhimurium and then with PGPE. The extract was found to have significant effects on mortality and the numbers of viable S. typhimurium recovered from feces. Although clinical signs and histological damage were rarely observed in the treated mice, the untreated controls showed signs of lethargy and histological damage in the liver and spleen. Taken together, the results of this study indicate that PGPE has the potential to provide an effective treatment for salmonellosis.
    Evidence-based Complementary and Alternative Medicine 09/2009; 2011:690518. · 1.72 Impact Factor
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    ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) is serious clinical urgent problems worldwide. In the present study, the antibacterial activity of Hylomecon hylomeconoides was investigated. The EtOH extract and its fraction (n-hexane, CH(2)Cl(2), EtOAc, and H(2)O) were investigated against MRSA. The most active extract (CH(2)Cl(2)) led to the isolation of 6-methoxydihydrosanguinarine (6-MS), 6-acetonylhydrosanguinarine, and dihydrosanguinarine. These compounds were very active against MRSA strains with minimum inhibitory concentrations (MICs) ranging from 1.95 to 250 microg/ml. Our study did however focus on 6-MS as it appeared to be the most active with MICs in the range of 1.9 to 3.9 microg/ml. These results encourage us to think that 6-MS can be used as a natural antibacterial agent.
    Applied biochemistry and biotechnology 08/2009; 160(8):2467-74. · 1.94 Impact Factor
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    ABSTRACT: Resveratrol is a phytoalexin polyphenolic compound found in various plants, including grapes, berries, and peanuts. Recently, studies have documented various health benefits of resveratrol including cardiovascular and cancer-chemopreventive properties. The aim of the present study was to demonstrate the effects of resveratrol on the expression of pro-inflammatory cytokines, as well as to elucidate its mechanism of action in the human mast cell line (HMC-1). Cells were stimulated with phorbol 12-myristate 13-acetate (PMA) plus A23187 in the presence or absence of resveratrol. To study the possible effects of resveratrol, ELISA, RT-PCR, real-time RT-PCR, Western blot analysis, fluorescence, and luciferase activity assays were used in this study. Resveratrol significantly inhibited the PMA plus A23187-induction of inflammatory cytokines such as tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and IL-8. Moreover, resveratrol attenuated cyclooxygenase (COX)-2 expression and intracellular Ca2+ levels. In activated HMC-1 cells, phosphorylation of extra-signal response kinase (ERK) 1/2 decreased after treatment with resveratrol. Resveratrol inhibited PMA plus A23187-induced nuclear factor (NF)-kappaB activation, IkappaB degradation, and luciferase activity. Resveratrol suppressed the expression of TNF-alpha, IL-6, IL-8 and COX-2 through a decrease in the intracellular levels of Ca2+ and ERK 1/2, as well as activation of NF-kappaB. These results indicated that resveratrol exerted a regulatory effect on inflammatory reactions mediated by mast cells.
    Pharmacological Research 06/2009; 59(5):330-7. · 4.35 Impact Factor
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    ABSTRACT: In this study, we evaluated the effect of 5-hydroxytryptophan on anti-inflammatory and analgesic activity in RAW 264.7 cells. Cells were treated with different concentrations of 5-hydroxytryptophan for either 1 h or for 24 h. The anti-inflammatory effect was then analyzed by enzyme-linked immunosorbent assay (ELISA), Western blotting and reverse transcription polymerase chain reaction (RT-PCR). In addition, the analgesic activity was evaluated by measuring the acetic acid-induced writhing response. We found that 5-hydroxytryptophan significantly reduced the acetic acid-induced writhing response. Moreover we evaluated the effects of 5-hydroxytryptophan on the release of several inflammatory mediators including nitric oxide (NO) and interleukin-6 (IL-6). Our results demonstrated that 5-hydroxytryptophan inhibited the lipopolysaccharide (LPS)-induced expression of NO and IL-6. Furthermore, we found that 5-hydroxytryptophan played a role in LPS induced inducible nitric oxide synthase (iNOS), cyclo oxygenase-2 (COX-2) and extracellular-signal regulated protein kinase (ERK) activation. Taken together, these results indicate that 5-hydroxytryptophan has the potential for use in the treatment of inflammatory disease and as an analgesic.
    Biological & Pharmaceutical Bulletin 05/2009; 32(4):553-7. · 1.85 Impact Factor
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    ABSTRACT: Methyl gallate is a major component of Galla Rhois, as carvacrol is of oregano essential oils. Both have shown good antibacterial activity against intestinal bacteria. This study investigated the antibacterial activities of nalidixic acid in combination with methyl gallate and carvacrol against nalidixic acid resistant bacteria. The combined effect of nalidixic acid with methyl gallate and carvacrol was evaluated using the checkerboard method to obtain a fractional inhibitory concentration index. The results showed that the combinations of nalidixic acid + methyl gallate/carvacrol improved nalidixic acid resistant pathogenic bacteria inhibition with synergy or partial synergy activity. Thus, a strong bactericidal effect of the drug combinations was observed. In vitro data thus suggested that nalidixic acid combined with methyl gallate and carvacrol may be microbiologically beneficial, rather than antagonists.
    Molecules 02/2009; 14(5):1773-80. · 2.43 Impact Factor
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    ABSTRACT: We evaluated the in vivo anti-inflammatory and analgesic activities of orally administered paeonol in mice, and also investigated the anti-inflammatory activity of paeonol in a cell line. Paeonol significantly reduced the edema induced by arachidonic acid in rats. The analgesic effects were assayed using 2 different models, i.e., by acetic acid-induced writhing response and by formalin induced licking and biting time. Moreover, we examined the effects of paeonol on the release of inflammatory mediators such as NO, PGE(2) and IL-6. Our results demonstrated that paeonol inhibited LPS induced expression of NO, PGE(2) and IL-6. Paeonol prevented LPS induced iNOS, COX-2 and ERK activation. Therefore, paeonol appears to have potential as a treatment for inflammatory disease and analgesic.
    The American Journal of Chinese Medicine 02/2009; 37(1):181-94. · 2.28 Impact Factor
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    ABSTRACT: Resveratrol is a polyphenol compound and prominent anti-inflammatory agent found in plants, including the fruits of Morus alba. However, the therapeutic mechanisms of resveratrol remain largely unclear. To gain insight into the biological effects of resveratrol, we examined its influence on LPS-induced IL-8 production in the human monocytic cell line, THP-1. In inflammatory diseases, IL-8 plays a central role in the initiation and maintenance of inflammatory response. In the present study, IL-8 production was measured by ELISA and RT-PCR, while MAPK activation, IkappaBalpha degradation, nuclear factor (NF)-kappaB activation and cyclooxygenase (COX)-2 expression were determined by Western blot analysis. Resveratrol inhibited LPS-induced IL-8 production in a dose-dependent manner. Furthermore, resveratrol inhibited extracellular signal-regulated kinase (ERK) and p38 MAPK phosphorylation, IkappaBalpha degradation, NF-kappaB activation and cyclooxygenase (COX)-2 expression, which suggest that resveratrol inhibits IL-8 secretion by blocking MAPK phosphorylation and NF-kappaB activation. Taken together, these findings may help elucidate the mechanism by which resveratrol modulates THP-1 cell activation under inflammatory conditions.
    The American Journal of Chinese Medicine 01/2009; 37(6):1203-14. · 2.28 Impact Factor
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    ABSTRACT: Salmonella remains a primary cause of food poisoning worldwide, and massive outbreaks have been witnessed in recent years. Therefore, this study investigated the antimicrobial activity of methyl gallate (MG), which exhibited good antibacterial activity (MIC=3.9-125 mg/ml) against all the bacterial strains tested. In a checkerboard dilution test, MG markedly lowered the MICs of ciprofloxacin (CPFX) against Salmonella. The combined activity of CPFX and MG against Salmonella resulted in fractional inhibitory concentrations (FICs) ranging from 0.0037 to 0.015 and from 0.24 to 7.8 mg/ml, respectively. Meanwhile, the FIC index ranged from 0.31-0.37, indicating a marked synergistic relationship between CPFX and MG against Salmonella. Time-kill assays also showed a decrease in the CFU/ml between the combination and the more active compound. Therefore, this study demonstrated that MG and CPFX can act synergistically in inhibiting Salmonella in vitro.
    Journal of Microbiology and Biotechnology 12/2008; 18(11):1848-52. · 1.40 Impact Factor
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    ABSTRACT: Macrophages play central roles in the innate immune system. The roots of Aralia cordata are widely used in Oriental medicine as a remedy for arthritis. During our program to screen medicinal plants for potential anti-inflammatory compounds, ent-pimara-8(14), 15-dien-19-oic acid (pimaradienoic acid; PA) was isolated from the roots of A. cordata. We examined the effect of PA on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. PA was found to significantly inhibit the production of nitric oxide (NO), prostaglandin E(2) (PGE(2)), and interleukin-6 (IL-6), as well as the expressions of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and IL-6. Furthermore, we examined whether mitogen-activated protein kinases (MAPKs) and phosphatidylinositol 3-kinase (PI3K) signaling pathways are involved in LPS-induced RAW 264.7 cells. We found that a p38 inhibitor (SB203580) and an ERK 1/2 inhibitor (PD98059) significantly affected LPS-induced IL-6 production. In contrast, a JNK 1/2 inhibitor (SP600125) and PI3K inhibitor (wortmannin or LY294002) did not block the induction of IL-6 production by LPS. The LPS-induced phosphorylation of p38 MAPK and extracellular signal-regulated kinase 1/2 (ERK1/2) was inhibited by PA, but not the phosphorylation of JNK 1/2 and AKT (Ser473). Moreover, PA suppressed I kappaB alpha degradation, NF-kappaB activation and luciferase activity. These results suggest that PA isolated from A. cordata has a potential regulatory effect on inflammatory iNOS, COX-2 and IL-6 expression through blockade of the phosphorylation of MAPKs following I kappaB alpha degradation and NF-kappaB activation.
    European journal of pharmacology 11/2008; 601(1-3):179-85. · 2.59 Impact Factor
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    ABSTRACT: The antimicrobial killing activity toward methicillin-resistant Staphylococcus aureus (MRSA) has been a serious emerging global issue. New effective antimicrobials and/or new approaches to settle this issue are urgently needed. The oriental herb, Alpinia officinarum, has been used in Korea for several hundreds of years to treat various infectious diseases. As it is well known, one of the active constituents of Alpinia officinarum is galangin. Against the 17 strains, the minimum inhibitory concentrations (MICs) of galangin (GAL) were in the range of 62.5 ~ 125 microg/ml, and the MICs of gentamicin (GEN) ranged from 1.9 microg/ml to 2,000 microg/ml. The fractional inhibitory concentrations (FICs) of GAL, in combination with GEN, against 3 test strains were 0.4, 3.9, and 250 microg/ml, and were all 15.62 microg/ml in GEN. The FIC index showed marked synergism in the value range of 0.19 to 0.25. By determining time-kill curves, also confirmed the low synergism of the GAL and GEN combination against 4 h, 8 h, 12 h, and 24 h cultured MRSA. The time-kill study results indicated a low synergistic effect against 3 test strains. Thus, the mixture of GAL and GEN could lead to the development of new combination antibiotics against MRSA infection.
    The Journal of Microbiology 07/2008; 46(3):283-8. · 1.28 Impact Factor

Publication Stats

129 Citations
12 Downloads
2k Views
45.69 Total Impact Points

Institutions

  • 2012–2013
    • National Institute of Horticultural and Herbal Sciences
      Junten, South Jeolla, South Korea
  • 2007–2013
    • Wonkwang University
      • College of Pharmacy
      Iksan, North Jeolla, South Korea