Young Wan Ha

Seoul National University, Seoul, Seoul, South Korea

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Publications (22)61.71 Total impact

  • Article: Induction of apoptosis by ginsenoside Rk1 in SK-MEL-2-human melanoma.
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    ABSTRACT: Ginsenosides are active compounds isolated from Panax ginseng Meyer. Among these ginsenosides, less polar ginsenosides such as ginsenoside Rg3 and ginsenoside Rh2 have been demonstrated to have tumor inhibitory effects because of their cytotoxicity. In this study, we evaluated the apoptotic effects of ginsenoside Rk1 in SK-MEL-2 human melanoma. Ginsenoside Rk1 isolated from red ginseng is one of the novel ginsenosides that shows strong cytotoxicity compared to ginsenoside Rg3 in dose- and time-dependent manners. The results of DNA fragmentation, 4',6-diamidino-2-phenylindole staining, and flow cytometric analysis are corroborated that ginsenoside Rk1 induced apoptosis in SK-MEL-2 cells. Western blot analysis revealed up-regulation of Fas, FasL, and Bax protein expression and down-regulation of procaspase-8, procaspase-3, mutant p53 and Bcl-2 protein expression. These findings suggest that ginsenoside Rk1 might be a promising compound to induce apoptosis through both extrinsic and intrinsic pathways in SK-MEL-2 cells.
    Archives of Pharmacal Research 03/2012; 35(4):717-22. · 1.59 Impact Factor
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    Article: Development of a rapid and convenient method to separate eight ginsenosides from Panax ginseng by high-speed counter-current chromatography coupled with evaporative light scattering detection.
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    ABSTRACT: Ginsenosides exhibit diverse biological activities and are major well-known components isolated from the radix of Panax ginseng C.A. Meyer. In the present work, a rapid and facile method for the separation and purification of eight ginsenosides from P. ginseng by high-speed counter-current chromatography coupled with evaporative light scattering detector (HSCCC-ELSD) was successfully developed. The crude samples for HSCCC separation were first purified from ginseng extract using a macroporous resin; the extract was loaded onto a Diaion-HP20 column and fractionated by methanol and water gradient elution. The ginsenosides-protopanaxadiol (PPD) and protopanaxatriol (PPT) fractions were subsequently eluted with 65 and 80% methanol and water gradient elution, respectively. Furthermore, these two fractions were separated by HSCCC-ELSD. The two-phase solvent system used for separation was composed of chloroform/methanol/water/isopropanol at a volume ratio of 4:3:2:1. Each fraction obtained was collected and dried, yielding the following eight ginsenosides: Rg(1), Re, Rf, Rh(1), Rb(1), Rc Rb(2) and Rd. The purity of these ginsenosides was greater than 97% as assessed by HPLC-ELSD, and their structures were characterized by electrospray-ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance spectroscopy. This is the first report regarding the separation of the ginsenosides Rh(1), Rb(2) and Rc from P. ginseng by HSCCC.
    Journal of Separation Science 05/2011; 34(10):1116-22. · 2.73 Impact Factor
  • Article: Cellular uptake of ginsenosides in Korean white ginseng and red ginseng and their apoptotic activities in human breast cancer cells.
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    ABSTRACT: Panax ginseng has been reported to have cancer-preventive properties and, through anti-inflammatory, antioxidant, and pro-apoptotic mechanisms, to influence gene expression. However, the comparison of Korean white ginseng (WG) and red ginseng (RG) in their apoptotic effects and the identification of the selective cellular uptake of the ginsenosides in human breast cancer cells have not yet been fully understood. In the present study, the relative nonpolar and protopanaxadiol (PPD) class ginsenosides exhibited more cytotoxic and efficient cellular uptake on MCF-7 cells compared with the relative polar and protopanaxatriol (PPT) class compounds. PPD class ginsenosides were present in RG in a 2.5 times higher concentration as compared to WG, while PPT class ginsenosides were only present in WG. Thus, RG exerted more potent cytotoxicity than WG against MCF-7 and MDA-MB231 cells. RG also increased the sub-G1 DNA contents of the cell cycle and Annexin V-positive apoptotic bodies undergoing apoptosis through the caspase-3 activation in MCF-7 cells. In addition, RG downregulated the proliferative and anti-apoptotic gene products and potentiated paclitaxel-induced apoptosis in MCF-7 cells. Overall, RG contained a higher concentration of PPD class ginsenosides as compared to WG; the greater cellular uptake of PPD resulted in more substantial antiproliferative activity in human breast cancer cells.
    Planta Medica 01/2011; 77(2):133-40. · 2.15 Impact Factor
  • Article: Enzymatic transformation of platycosides and one-step separation of platycodin D by high-speed countercurrent chromatography.
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    ABSTRACT: Platycosides, the saponins found in the roots of Platycodon grandiflorum (Platycodi Radix), are typically composed of oleanane triterpenes with two side chains. In platycosides, platycodin D, a glucose unit at C-3, is a major component, which has several pharmacological activities. Because of the high demand for this compound, we attempted to enzymatically convert platycodin D(3) and platycoside E, having two and three glucose units at C-3, respectively, into platycodin D. In this study, we tested the ability of several glycosidases to transform platycosides, or more specifically, the ability to transform platycoside E and platycodin D(3) into platycodin D. To obtain pure platycodin D on a preparative scale, high-speed countercurrent chromatography with a solvent system of ethyl acetate/n-butanol/water (1.2:1:2, v/v/v) was used for the separation of the enzymatically transformed product. Approximately 39.4 mg of platycodin D (99.8% purity) was obtained from 200 mg of the product in a one-step separation. The results strongly support the advantage of enzymatic transformation of the platycosides for the efficient enrichment of platycodin D in the complicated extract of the medicinal plant.
    Journal of Separation Science 07/2010; 33(13):1916-22. · 2.73 Impact Factor
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    Article: Development and optimization of a method for the separation of platycosides in Platycodi Radix by comprehensive two-dimensional liquid chromatography with mass spectrometric detection.
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    ABSTRACT: Comprehensive two-dimensional chromatography (LCxLC) using combinations of two columns (C(18) x CN and C(18) x NH(2)) was employed with electrospray (ESI) mass spectrometry to analyze platycosides from root extract. Based on the capability of the C(18), CN and NH(2) columns to separate the platycosides, the orthogonality in two-dimensional space according to each combination of columns was predicted from the correlation coefficients between the retention times of the 17 compounds separated by the independent CN and C(18) columns, and NH(2) and C(18) columns. The expected distribution of the peaks was also compared with the two-dimensional plots obtained by practical separation in an LCxLC system. The increased peak capacities using C(18) x NH(2) allowed three minor components and five isomers of the platycosides to be newly separated, which were not identified with 1D-LC using the individual C(18) column, whereas the combination of C(18) x CN did not result in any improvement of the separation performance.
    Journal of chromatography. A 06/2010; 1217(26):4375-82. · 4.19 Impact Factor
  • Article: Validated quantification for selective cellular uptake of ginsenosides on MCF-7 human breast cancer cells by liquid chromatography-mass spectrometry.
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    ABSTRACT: The cellular behavior of ginsenosides on cancer cells has not been measured directly despite their potent anticancer activities and biological actions. A liquid chromatography-mass spectrometry (LC-MS) method was developed to measure the selective cellular uptake of ginsenosides in both cell lysates and culture media. Fifteen ginsenosides were separated within 17 min with good peak shapes using a 2-microm sub-particle size C18 column. Quantification was performed by triple-quadrupole MS with electrospray ionization in negative ion mode. The sample preparation containing the solid-phase extraction was linear (correlation coefficient, r(2) > 0.992) for all analytes, while the limit of quantification ranged from 0.5 to 2.0 ng/mL in both matrices. The assay precision (%CV) and accuracy (%bias) at three different concentrations (5, 20, and 100 ng/mL) were 1.4% to 11.6% and 94.9% to 106.4%, respectively. When this method was used to examine the selective cellular uptake of ginsenosides, the relative non-polar and protopanaxadiol class ginsenosides, such as Rg3, Rk1, Rg5, Rh2, compound-K, and protopanaxadiol (PPD), showed cellular uptake in the MCF-7 cells, but the relative polar and protopanaxatriol class of ginsenosides did not accumulate in the cells. The most non-polar ginsenoside PPD, which is an aglycone of the protopanaxadiol type, resulted in the highest uptake rate. These results show that the different anticancer activities are due to the selective uptake of ginsenosides based on their chemical structures. This LC-MS-based method can be used to estimate the biological activity of ginsenosides on cells from their structural diversity.
    Analytical and Bioanalytical Chemistry 02/2010; 396(8):3017-25. · 3.78 Impact Factor
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    Article: Systematic error in gas chromatography-mass spectrometry-based quantification of hydrolyzed urinary steroids.
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    ABSTRACT: Gas chromatography-mass spectrometry-based metabolite profiling can lead to an understanding of various disease mechanisms as well as to identifying new diagnostic biomarkers by comparing the metabolites related in quantification. However, the unexpected transformation of urinary steroids during enzymatic hydrolysis with Helix pomatia could result in an underestimation or overestimation of their concentrations. A comparison of beta-glucuronidase extracted from Escherichia coli revealed 18 conversions of 84 steroids tested as an unexpected transformation under hydrolysis with beta-glucuronidase/arylsulfatase extracted from Helix pomatia. In addition to the conversion of 3beta-hydroxy-5-ene steroids into 3-oxo-4-ene steroids, which has been reported, the transformation of 3beta-hydroxy-5alpha-reduced and 3beta-hydroxy-5beta-reduced steroids to 3-oxo-5alpha-reduced and 3-oxo-5beta-reduced steroids, respectively, was newly observed. The formation of by-products was in proportion to the concentration of substrates becoming saturated against the enzyme. The substances belonging to these three steroid groups were undetectable at low concentrations, whereas the corresponding by-products were overestimated. These results indicate that the systematic error in the quantification of urinary steroids hydrolyzed with Helix pomatia can lead to a misreading of the clinical implications. All these hydrolysis procedures are suitable for study purposes, and the information can help prevent false evaluations of urinary steroids in clinical studies.
    Cancer Epidemiology Biomarkers &amp Prevention 02/2010; 19(2):388-97. · 4.12 Impact Factor
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    Article: Evaluation of plasma enzyme activities using gas chromatography-mass spectrometry based steroid signatures.
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    ABSTRACT: The simultaneous quantification of 65 plasma steroids, including 22 androgens, 15 estrogens, 15 corticoids and 13 progestins, was developed using gas chromatography-mass spectrometry (GC-MS). The extraction efficiency of the catechol estrogens was improved by the addition of l-ascorbic acid in several steps. All steroids, as their trimethylsilyl derivatives, were well separated with good peak shapes within a 50min run. The devised method provided good linearity (correlation coefficient, r(2)>0.993), while the limit of quantification ranged from 0.2 to 2.0ngmL(-1). The precision (% CV) and accuracy (% bias) were 2.0-12.4% and 93.5-109.2%, respectively. The metabolic changes were evaluated by applying this method to plasma samples obtained from 26 healthy male subjects grouped according to the pre- and post-administration of dutasteride, which inhibits 5alpha-reductase isoenzyme types 1 and 2. The levels of three plasma steroids, such as dihydrotestosterone, 5alpha-androstanedione and allotetrahydrocortisol, were decreased significantly after drug administration, while the levels of testosterone and 5beta-androstane-3beta,17alpha-diol were increased. In addition, the ratios of the steroid precursors and their metabolites, which represent the activities of the related enzymes, were z-score transformed for visualization in heat maps generated using supervised hierarchical clustering analysis. These results validated the data transformation because 5alpha-reductase is an indicator for the biological actions of dutasteride. GC-MS base quantitative visualization might be found in the integration with the mining biomarkers in drug evaluations and hormone-dependent diseases.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 11/2009; 877(32):4125-32. · 2.78 Impact Factor
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    Article: Liquid chromatography/mass spectrometry-based structural analysis of new platycoside metabolites transformed by human intestinal bacteria.
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    ABSTRACT: Platycosides, the main active constituents of Platycodi Radix, have been thoroughly studied for the characterization of their potent biological activities. However, metabolism of platycosides has not yet been characterized. A HPLC electrospray ionization-tandem mass spectrometry (LC/ESI-MS(n)) approach was applied to new complex platycoside metabolites transformed by human intestinal bacteria to identify their structures and determine metabolic pathway. The molecular weights of metabolites were identified by LC/ESI-MS analysis in both positive and negative modes. Structures for the platycoside metabolites were proposed by the molecular weights and the expected enzymatic activity of intestinal microbes on platycoside. In the second step, successive LC-MS(n) analysis was used to demonstrate the proposed structures. Under ESI tandem mass conditions, the sequential fragmentation patterns of [M+Na](+) ions exclusively showed signals, consistent with the cleavage of glycoside bonds, rearrangement and some cross-ring cleavage, thus allowing the rapid identification of platycoside metabolites. The metabolites identified in the time-dependent metabolism experiments enable us to propose several microbial pathways for platycosides. Even though the metabolites of some platycosides may have unknown structures and low levels, the analytical tools presented in this study made it possible to obtain a rapid and complete characterization of new metabolites and their metabolism pathway in human intestinal bacteria.
    Journal of pharmaceutical and biomedical analysis 09/2009; 51(1):202-9. · 2.45 Impact Factor
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    Article: Isolation and tandem mass fragmentations of an anti-inflammatory compound from Aralia elata.
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    ABSTRACT: One-step isolation of a saponin from Aralia elata was undertaken using high-speed countercurrent chromatography coupled with evaporative light scattering detection. A triterpenoid saponin, elatoside F, was purified with 96.8% purity using a two-phase-system comprising chloroform-methanol-water-isopropanol. The yield was 35.0 mg from 348.2 mg of the enriched saponin fraction. In vitro anti-inflammatory study demonstrated that elatoside F inhibited lipopolysaccharide-induced nitric oxide production, as well as nuclear factor kappaB activation, in a dose-dependent manner. Two types of mass ionization technique were compared on elatoside F to investigate characteristic fragmentation patterns. MALDI-TOF tandem mass spectrometric fragmentation patterns of sodiated ions provided structural information on glycosidic cleavages and on extensive cross-ring cleavages. Electrospray ionization multiple-stage tandem mass fragmentation of both sodiated and lithiated ions could provide information on glycosidic cleavages. All observed tandem mass fragmentation spectra provided valuable elatoside F structural information when unknown samples from crude extracts are under screening by mass spectrometry.
    Archives of Pharmacal Research 07/2009; 32(6):831-40. · 1.59 Impact Factor
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    Article: Generation and characterization of monoclonal antibody to ginsenoside rg3.
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    ABSTRACT: While studying the mechanism of ginsenoside Rg3 (G-Rg3) on tumor inhibition, we produced monoclonal antibody to G-Rg3 for more specific investigation. We immunized Balb/c mice to G-Rg3 conjugated bovine serum albumin (BSA) by intraperitoneal injection and hybridized splenocytes from those immunized mice and myeloma cells. From those fusion cell lines, we selected productive monoclonal clones and obtained culture media containing monoclonal antibody to G-Rg3. After purification, we performed enzyme-linked immunosorbent assay (ELISA) to verify the sensitivity and specificity of the antibody. When compared with G-Rh2 having a very similar structure as a metabolite of G-Rg3, the antibody worked only with G-Rg3 in a concentration-dependent manner. We confirmed that the monoclonal antibody to G-Rg3 can be applied to immunocytochemistry for detection of the treated G-Rg3 inside A549 human lung adenocarcinomas. Thus, the monoclonal antibody to G-Rg3 would be a useful tool for measuring the bioactivity of G-Rg3 in various fields.
    Biological & Pharmaceutical Bulletin 05/2009; 32(4):548-52. · 1.66 Impact Factor
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    Article: Preparative isolation of six major saponins from Platycodi Radix by high-speed counter-current chromatography.
    Young Wan Ha, Yeong Shik Kim
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    ABSTRACT: Platycosides, the primary constituents of Platycodi Radix, are known to have numerous and varied biological activities, exerting anti-inflammation, anti-allergy, anti-tumour, anti-obesity and anti-hyperlipidemia effects. However, effective methods for isolating and purifying platycosides from Platycodi Radix are not currently available. To develop an efficient method for the preparative separation of six platycosides from Platycodi Radix by high-speed counter-current chromatography (HSCCC) coupled with an evaporative light scattering detection (ELSD) system. Preparative separation was performed by water extraction using reversed-phase C(18) column chromatography on an HSCCC-ELSD system. A two-phase solvent system comprised hexane-n-butanol-water (1:40:20, v/v) and (1:10:5, v/v) was employed. Two other key parameters, revolution speed of the separation column and flow-rate of the mobile phase, were also investigated for optimum HSCCC performance. Each peak fraction obtained from separation of the platycosides was collected according to the ELSD elution profile and determined by HPLC. Using the described method, six platycosides, all with purities of over 94%, could be isolated from 300 mg of the platycoside-enriched fraction. Their structures were characterized by electrospray ionisation mass spectrometry (ESI-MS), (1)H-NMR and (13)C-NMR. Six of the main bioactive platycosides in Platycodi Radix could be isolated and purified systematically by HSCCC.
    Phytochemical Analysis 03/2009; 20(3):207-13. · 2.63 Impact Factor
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    Article: Anti-inflammatory activity of prosapogenin methyl ester of platycodin D via nuclear factor-kappaB pathway inhibition.
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    ABSTRACT: Platycodin D (PD) isolated from Platycodi Radix has been reported to have anti-inflammatory and anti-tumor activities. In this study, we have investigated anti-inflammatory activities of prosapogenin D (PrsD) and prosapogenin D methyl ester (PrsDMe) of PD. The results indicated that PrsDMe concentration-dependently inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production, however, PrsD did not inhibit NO production in LPS-induced macrophages. Furthermore, PrsDMe inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) without appreciable cytotoxic effects. In the transfectant RAW 264.7 cells, PrsDMe was observed to reduce the level of nuclear factor-kappaB (NF-kappaB) activity. PrsDMe also inhibited the degradation of an inhibitory protein called inhibitor kappaB (IkappaB). Therefore, it was suggested that PrsDMe inhibited the expression of LPS-induced iNOS and COX-2 genes by suppressing NF-kappaB activation at the transcriptional level. Also, PrsDMe showed carrageenan-induced acute anti-inflammatory activity and the adjuvant-induced anti-arthritic activity in mice. In conclusion, we suggest that these compounds exert an anti-inflammatory effect through the regulation of the NF-kappaB pathway. The different activities of PD, PrsD and PrsDMe are based on the structure of the sugar substituent or methyl group at the C28-carboxyl position.
    Biological & Pharmaceutical Bulletin 12/2008; 31(11):2114-20. · 1.66 Impact Factor
  • Article: Structural analysis of platycosides in Platycodi Radix by liquid chromatography/electrospray ionization-tandem mass spectrometry.
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    ABSTRACT: Platycosides extracted from Platycodi Radix were analyzed by HPLC coupled with electrospray ionization multistage tandem mass spectrometry (HPLC/ESI-MS(n)). Predominant [M+Na](+) ions in positive mode and [M-H](-) ions in negative mode in the direct ESI-MS spectra of extract provided information on molecular weights, but minor components and isomers could not be discriminated. However, combining HPLC and ESI-MS(n), allowed eleven platycosides, including four acetylated platycodin isomers and two prosapogenines to be analyzed. During MS(2) analysis conducted to elucidate the structures of platycosides, fragment ions provided information on sugar moieties attached at C-28 of triterpene structure of the platycosides. Glycosidic bond cleavages at C-3 were revealed by fragment ions in MS(3) spectra. Some characteristic fragment ions not related to sugar bond cleavage revealed that an esterified triterpene is linked to sugars at C-28. The only sugar ring-cross cleavage corresponding to 90 Da in the negative MS(2) spectrum took place at an arabinosyl sugar moiety. By using HPLC/ESI-MS(n), three acetylated platycosides in Platycodi Radix extract were newly identified.
    Journal of Chromatography 06/2008; 1189(1-2):467-75. · 4.53 Impact Factor
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    Article: Simultaneous quantification of 14 ginsenosides in Panax ginseng C.A. Meyer (Korean red ginseng) by HPLC-ELSD and its application to quality control.
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    ABSTRACT: A new method of high-performance liquid chromatography coupled with evaporative light scattering detection (HPLC-ELSD) was developed for the simultaneous quantification of 14 major ginsenosides, which are the marker compounds of Panax ginseng C.A. Meyer (Korean red ginseng). Various types of ginseng samples were extracted, and the amounts of the 14 ginsenosides (Rg1, Re, Rf, Rh1, Rg2, Rb1, Rc, Rb2, Rb3, Rd, Rg3, Rk1, Rg5, and Rh2) were determined by reverse-phase HPLC-ELSD using digoxin as an internal standard. The mobile phase consisted of a programmed gradient of aqueous acetonitrile. Calibration curves for each ginsenoside were determined for the quantification. The method was validated for linearity, precision, accuracy, limit of detection, and limit of quantification. This quantification method was applied to several finished ginseng products including white ginseng, red ginseng powder, and red ginseng concentrate. The amounts of the 14 ginsenosides in the various ginseng samples could be analyzed simultaneously. This validated HPLC method is expected to provide a new basis for the quality assessment of ginseng products.
    Journal of Pharmaceutical and Biomedical Analysis 10/2007; 45(1):164-70. · 2.97 Impact Factor
  • Article: Relationship between eggshell strength and keratan sulfate of eggshell membranes.
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    ABSTRACT: Eggshell strength is an important factor in an effort to minimize eggshell breakage, which is a significant problem in the egg production industry. In the current study, we isolated and quantified the specific glycosaminoglycans (GAGs) from the calcified eggshell and shell membranes, which are related to eggshell strength. Our data suggest that GAGs exist in calcified eggshell may influence morphology of shell but do not affect on increase of shell amount while GAGs of shell membranes are maybe highly associated with shell strength with an increase of shell weight. Shell strength showed a strong correlation with the content of GAGs (r=0.942, p<0.0005) and a weak relationship with uronic acid content (r=0.564, p=0.056) in shell membranes. Monosaccharides in shell membranes were determined by Bio-LC analysis for the identification of any specific GAGs related with shell strength. It indicates that the galactose content as a component of keratan sulfate (KS) has a significant correlation with eggshell strength (r=0.985, p<0.0005). These results suggest that eggshell strength is proportional to the KS content of eggshell membranes with an increase of eggshell weight.
    Comparative Biochemistry and Physiology - Part A Molecular & Integrative Physiology 09/2007; 147(4):1109-15. · 2.23 Impact Factor
  • Article: Preparative isolation of four ginsenosides from Korean red ginseng (steam-treated Panax ginseng C. A. Meyer), by high-speed counter-current chromatography coupled with evaporative light scattering detection.
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    ABSTRACT: Ginseng (Panax ginseng C. A. Meyer) has been well known to have a variety of ginsenosides that show diverse biological activities. Especially, the components of ginsenosides are quite different depending on the processing method. Recently, there have been several reports showing that less polar ginsenosides from Korean red ginseng (steam-treated Panax ginseng) have potent biological activities such as radical scavenging, vasodilating and anti-tumor activities. In this study, we have isolated four known ginsenosides Rg3, Rk1, Rg5 and F4 from Korean red ginseng by high-speed counter-current chromatography (HSCCC) coupled with evaporative light scattering detection (ELSD). The enriched saponin fraction (350 mg) was separated by using methylene chloride-methanol-water-isopropanol (6:6:4:1, v/v) as the two-phase solvent system and yielded 28.6 mg of Rg5, 26.6 mg of Rk1, 32.2 mg of Rg3 and 8.1 mg of F4. The purity of these ginsenosides was assessed by HPLC-ELSD to be over 95%, and their structures were characterized by electrospray ionization mass spectrometry (ESI-MS), (1)H NMR and (13)C NMR.
    Journal of Chromatography 07/2007; 1151(1-2):37-44. · 4.53 Impact Factor
  • Article: Qualitative and quantitative determination of ten major saponins in Platycodi Radix by high performance liquid chromatography with evaporative light scattering detection and mass spectrometry.
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    ABSTRACT: Saponins in Platycodi Radix (platycosides) exhibit potent biological activities in mammalian systems, including several beneficial effects such as anti-inflammatory, immunomodulatory and anti-obesity activities. In this study, we developed a new HPLC separation coupled with evaporative light scattering detector (ELSD) for the simultaneous quantitative determination of ten major saponins in Platycodi Radix. Simultaneous separation of these saponins was achieved on a C18 analytical column. The mobile phase consisted of a gradient of aqueous acetonitrile. The method was validated for linearity, precision, accuracy, limit of detection and quantification. Electrospray ionization mass spectrometry (ESI-MS) and liquid chromatography coupled with on-line mass spectrometry (LC-ESI MS/MS) were applied to identify platycosides in the purified fractions and in the crude extract. Under ESI-MS/MS conditions, the fragmentation patterns of [M-H]- ions exclusively show signals corresponding to cleavage of the glycosidic bonds, thus allowing a rapid identification of saponins in the crude extract of Platycodi Radix. The validated HPLC method provides a new basis of overall assessment on quality of Platycodi Radix, and ESI-MS/MS and LC-ESI MS/MS approaches offers analytical tools for a rapid screening of platycosides in the crude extract.
    Journal of Chromatography 12/2006; 1135(1):27-35. · 4.53 Impact Factor
  • Article: Cholesterol-lowering effect of platycodin D in hypercholesterolemic ICR mice.
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    ABSTRACT: This study investigates the in vivo hypocholesterolemic action of platycodin D and its in vitro evidence for the cholesterol-lowering properties. In order to examine the effects of platycodin D on hypercholesterolemia in male ICR mice, platycodin D with doses of 15, 30 or 50 mg/kg was orally administered for 8 weeks. Changes in body weight and daily food intake were measured regularly during the experimental period. Final contents of triglyceride and different types of cholesterol in the serum, livers and feces were determined. The effects of platycodin D on cholesterol metabolism were further investigated with several in vitro assays, including antioxidant effect on low density lipoprotein oxidation, inhibition of human acyl-coenzyme A:cholesterol acyltransferase (hACAT) and serum lipoprotein associated-phospholipase A(2) (Lp-PLA(2)), as well as the regulation of farnesoid X receptor. The formation of insoluble complex between platycodin D and cholesterol was also investigated. Following an eight week experimental period, the body weights of platycodin D-fed mice were less than those of control mice on a high cholesterol diet by 11.2+/-5% (P<0.01) with 15 mg/kg platycodin D, 11.7+/-5% (P<0.01) with 30 mg/kg platycodin D, and 23.4+/-7.9% (P<0.0001) with 50 mg/kg platycodin D, respectively. A decrease in daily food consumption was also noted in most of the treated animals. Triglyceride and cholesterol concentrations were decreased in serums and livers, but increased in feces. Some of the in vitro observations revealed that the hypocholesterolemic effect of platycodin D is partly associated with inhibition to hACAT activity and antagonism to the farnesoid X receptor as well as the formation of insoluble complex with between platycodin D and cholesterol. Both in vivo and in vitro results demonstrate a potential value of platycodin D as a novel cholesterol-lowering and anti-atherogenic candidate.
    European Journal of Pharmacology 06/2006; 537(1-3):166-73. · 2.52 Impact Factor
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    Article: Anti-obesity effect of Pinellia ternata extract in Zucker rats.
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    ABSTRACT: Pinellia ternata is known as the herb effective in removing dampness-phlegm, one of the causes of obesity in traditional Korean medicine. Pinellia ternata water extract (PE) was fed to rats after mixing with diet once a day (400 mg x kg(-1)) for 6 weeks. We investigated its effect on the thermogenesis and fatty acids oxidation with obese Zucker rats. We also determined the gene expression of uncoupling protein 1 (UCP1), peroxisome proliferators-activated receptor alpha (PPARalpha), and PPARgamma coactivator 1alpha (PGC1alpha). The PE treatment lowered the levels of triglyceride and free fatty acids (p<0.05) in blood of the obese rats and the body weight was also reduced slightly. It was also observed that PE significantly increased the expression of both UCP1 mRNA in brown adipose tissue (BAT) (p<0.001) and PPARalpha and PGC1alpha mRNA in white visceral adipose tissue (WAT) (p<0.05 and p<0.001, respectively), which may cause a reduction of obesity. These results suggested that PE would be able to affect anti-obesity through thermogenesis and fatty acid oxidation.
    Biological & Pharmaceutical Bulletin 06/2006; 29(6):1278-81. · 1.66 Impact Factor