Won-Sik Choi

Soonchunhyang University, Asan, South Chungcheong, South Korea

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Publications (12)9.97 Total impact

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    ABSTRACT: In this study, ethanolic extracts from Hericium erinaceum cultivated with Artemisia capillaris (HEAC) were assessed for their ability to lower the cholesterol levels of male Sprague-Dawley rats fed a high-fat diet. Rats were randomly subdivided into seven test groups. Each group contained eight rats fed a high-fat diet during a growth period lasting 4 wk. Supplementation with the extracts was performed once a day for 2 wk after the high-fat diet. The control group (rats fed a high-fat diet) showed a high efficiency ratio (feed efficiency ratio) value compared to the normal group. Biochemical parameters, including total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-c), and triglyceride (TG) levels dramatically increased in the control group compared to the normal group. High-density lipoprotein-cholesterol (HDL-c) content in the control group was also significantly lower relative to the normal group. Two positive control groups, treated with simvastatin and atorvastatin, had lowered TC, LDL-c, and TG levels, and increased HDL-c content compared to the control group. Treatment with the tested extracts, including HEAC, ethanolic extracts from Hericium erinaceum, and ethanolic extracts from Artemisia capillaris reduced TC, LDL-c, and TG levels and elevated HDL-c content in the hyperlipidemia rats. The atherogenic index and cardiac risk factor values for the HEAC-treated group were 0.95 and 1.95, respectively. Simvastatin- and atorvastatin-treated groups showed atherogenic index values of 1.56 and 1.69, respectively, and cardiac risk factor values of 2.56 and 2.69, respectively. These results show HEAC possesses an ability to cure hyperlipidemia in rats and may serve as an effective natural medicine for treating hyperlipidemia in humans.
    Mycobiology 06/2013; 41(2):94-9.
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    ABSTRACT: Piperlongumine, a pyridone alkaloid isolated from Piper longum L., exhibited a potential inhibitory effect on washed rabbit platelet aggregation induced by collagen, arachidonic acid (AA) and platelet activating factor (PAF), without any inhibitory effect on that induced by thrombin. Piperlongumine was used as a lead compound for the synthesis of new antiplatelet agents. Seven synthetic compounds were newly synthesized from 3,4,5-trimethoxycinnamic acid (TMCA). They were 1-piperidin-1-yl-3-(3,4,5-trimethoxy-phenyl)prop-2-en-1-one (1'), 1-morpholin-4-yl-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (2'), 1-(3,5-dimethylpiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (3'), 1-(2-methylpiperidin-1-yl)-3-(3,4,5-tri-methoxyphenyl)prop-2-en-1-one (4'), 1-(3-hydroxypiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)- prop-2-en-1-one (5'), 1-[3-(3,4,5-tri-methoxyphenyl) acryloyl]-piperidin-2-one (6') and ethyl 1-[3-(3,4,5-trimethoxyphenyl)-acryloyl]piperidine-4-carboxylate (7'). Among those seven synthetic derivatives, 1-(3,5-dimethylpiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (3') had the most inhibitory effect on platelet aggregation induced by collagen, AA and PAF.
    Phytotherapy Research 09/2008; 22(9):1195-9. · 2.07 Impact Factor
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    ABSTRACT: Toxicity of various essential oils and their volatile components against the mushroom sciarid, Lycoriella mali was determined. The most potent fumigant toxicity was found in essential oil from thyme followed by the oils of sage, eucalyptus, and clove bud. α-Pinene was the most toxic fumigant compound found in thyme essential oil (LD50=9.85μl/l air) followed by β-pinene (LD50=11.85μl/l air) and linalool (LD50=21.15μl/l air). The mixture of α- and β-pinene exhibited stronger fumigant toxicity than α- or β-pinene itself against the mushroom fly adults. Therefore, thyme essential oil, α- and β-pinene could be potent fumigants to control mushroom flies during mushroom cultivation.
    Crop Protection - CROP PROT. 01/2006; 25(4):398-401.
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    ABSTRACT: The effects of methanol extract from Hericium erinaceus cultivated with Artemisia iwayomogi (HEAI) on proliferation of vascular smooth muscle cells and CCl(4)-induced hepatic damage were evaluated. HEAI was shown to have a potent inhibitory effect on the proliferation of vascular smooth muscle cells (VSMCs). Interestingly, a methanol extract of Hericium erinaceus showed no inhibitory effect on the proliferation of VSMCs, while a methanol extract of Artemisia iwayomogi possessed strong inhibitory effects on the proliferation of VSMCs. Therefore, the inhibitory effects of HEAI may be caused by the changes of chemical components in the culture broth after the addition of Artemisia iwayomogi in the HEAI growth media. HEAI also had a strong protective effect on CCl(4)-induced hepatic damage in rats. The activity was evaluated using biochemical parameters such as glutamic oxalacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and alkaline phosphatase (ALP). HEAI treatment caused a significant reduction in the activity of GOT but not of GPT and ALP in comparison with CCl(4) treatment alone. Histopathological studies showed that liver samples treated with HEAI were significantly different when compared to non-treated animals after CCl(4) exposure.
    Journal of Ethnopharmacology 09/2005; 100(1-2):176-9. · 2.76 Impact Factor
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    ABSTRACT: Five monoterpenes (carvacrol, p-cymene, linalool, alpha-terpinene, and thymol) derived from the essential oil of thyme (Thymus vulgaris) were examined for their repellency against the mosquito Culex pipiens pallens. All 5 monoterpenes effectively repelled mosquitoes based on a human forearm bioassay. Alpha-terpinene and carvacrol showed significantly greater repellency than a commercial formulation, N,N-diethyl-m-methylbenzamide (deet), whereas thymol showed similar repellency to that of deet. The duration of repellency after application for all these monoterpenes was equal to or higher than that of deet. These findings indicate that a spray-type solution containing 2% alpha-terpinene may serve as an alternative mosquito repellent.
    Journal of the American Mosquito Control Association 04/2005; 21(1):80-3. · 0.76 Impact Factor
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    ABSTRACT: Essential oils of Eulcalyptus globulus, Lavender officinalis, Rosemarinus officinalis, and Thymus vulgaris were examined for their repellent activities against Culex pipiens pallens. All 4 essential oils effectively repelled adult mosquitoes on hairless mice. Essential oil of T. vulgaris (thyme) had potent repellent activity within the tested materials, with a protection rate of 91% at a concentration of 0.05% topical treatment. Thyme essential oil significantly extended the duration of protection until 3 bites by mosquitoes. With gas chromatography-mass spectrometry analysis, thyme essential oil was a rich source of 5 monoterpenes, including in descending order thymol, p-cymene, carvacrol, linalool, and alpha-terpinene. These 5 monoterpenes also were assessed to determine their repellent activities to the mosquitoes. alpha-Terpinene had a potent repellent activity with a protection rate of 97% at a concentration of 0.05% topical treatment. Additionally, carvacrol and thymol showed an equivalent level of repellency. A spray-type solution containing 2% alpha-terpinene was tested for its repellent activity against Cx. pipiens. This solution showed stronger repellent activity than the currently used repellent N,N-diethyl-m-methylbenzamide (deet).
    Journal of the American Mosquito Control Association 01/2003; 18(4):348-51. · 0.76 Impact Factor
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    ABSTRACT: In the course of attempts to develop antimalarial drugs, we have designed and synthesized a series of quinoline alkaloide derivatives. Three of them, N-(4-methoxy-3,5-di-tert-butylbenzyl)cinchonidinium bromide (OSL-5), O-benzyl-N-(3,5-di-tert-butyl-4-methoxybenzyl)cinchonidinium bromide (OSL-7), and N-(3,5-di-tert-butyl-4-methoxybenzyl)quininium bromide (OSL-14) show potent activity against Plasmodium falciparum.
    Bioorganic & Medicinal Chemistry Letters 06/2002; 12(10):1351-5. · 2.34 Impact Factor
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    ABSTRACT: Fungicidal activity of Piper longum L. fruit-derived materials toward six phytopathogenic fungi, Pyricularia oryzae, Rhizoctonia solani, Botrytis cineria, Phytophthora infestans, Puccinia recondita, and Erysiphe graminis, was tested using a whole plant method in vivo. It was compared with synthetic fungicides (chlorothalonil, dichlofluanid and mancozeb) and four commercially available compounds (eugenol, piperine, piperlongumine, and piperettine) derived from P. longum. The response varied with the plant pathogen tested. At 1 mg ml−1, the hexane extract of P. longum showed fungicidal activities against P. oryzae, B. cineria, P. infestans, and P. recondita with the control values of 33, 15, 40, and 100%, respectively. A piperidine alkaloid, pipernonaline, was isolated from the hexane fraction using chromatographical techniques and showed a potent fungicidal activity against P. recondita with 91 and 80% control values at the concentration of 0.5 and 0.25 mg ml−1, respectively. Structural elucidation of pipernonaline was by means of MS, 1H-NMR and 13C-NMR. In the test with commercially available components derived from P. longum, piperettine exhibited weak activity against E. graminis, but no activity was observed from treatments with eugenol, piperine, and piperlongumine. In comparison, potent fungicidal activity showed with chlorothalonil against P. infestans at 50 μg ml−1, dichlofluanid against B. cinerea at 50 μg ml−1 and mancozeb against P. recondite at 5 μg ml−1. These results may be an indication of at least one of the fungicidal actions of pipernonaline derived from P. longum L. fruit.
    Crop Protection. 01/2001;
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    ABSTRACT: Toxicity of various essential oils and their volatile constituents towards the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in essential oil from eucalyptus (LD50=28.9 μl/l air). GC-MS analysis of essential oil from eucalyptus showed it to be rich in 1,8-cineole (81.1%), limonene (7.6%) and α-pinene (4.0%). Treatment of S. oryzae with each of these terpenes showed 1,8-cineole to be most active (LD50=23.5 μl/l air). In addition to 1,8-cineole, benzaldehyde (LD50=8.65 μl/l air) occurring in peach and almond kernels had a potent fumigant toxicity towards the rice weevils. Therefore, benzaldehyde and other natural volatiles could be a safer fumigant to control stored-grain insect pests than those currently used.
    Crop Protection. 01/2001;
  • Seok-Woo Nam, In-Young Choi, Won-Sik Choi
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    ABSTRACT: Fungicidal activity against phytopathogenic fungi of diarylthiazole compound of N-[4-(4-fluoro) phenyl-2-(N-methyl)piperidin-4-yl-thiazol-5-yl]pyrimidin-2-yl-N-(3-hydroxy-methyl)phenylamine (I) have been determined to be a superior and compound I was used as the leading compounds in this study. Furthermore, the synthesis of this compound was conducted by reacting them with four functional groups, N-cyclopropyl, N-cyclopentyl, N-cyclohexyl, and N-isopropylamine instead of the phenylamine. Also, 2-aminothiazole, 2-(N-ethoxycarbonyl)piperidin-4-yl, and 2-piperidin-4-ylthiazole were introduced as the leads instead of the 2-aminothiazole group of compound I. From this scheme, VIII-1∼VIII-4 and XII-1∼XIV-4 compounds were newly synthesized and their structures were confirmed by 1H-NMR-spectrum. The fungicidal activities of all the synthesized compounds against Phytophthora capsici were examined using the whole plant method. While the EC50 value of the commercial fungicide dimethomorph and I was 4.26 mM and that of N-[4-(4-fluoro phenyl-2-(N-methyl)piperidin-4-yl-thiazol-5-yl]pyrimidin-2-yl-cyclopropylamine (XIV-2) on P. capsici was 0.84 mM. Among the XII-1∼XIV-4 chemicals, XIV-2 showed the most potential antifungal activity in vivo. Therefore, XIV-2 can be considered as a viable candidate for the control of phytopathogenic diseases characterized by P. capsici infection, and further studies will be conducted on the mode of action XIV-2.
    Journal of the Korean Society for Applied Biological Chemistry 54(3). · 0.43 Impact Factor
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    ABSTRACT: Ethanol extract derived from Hericium erinaceum cultivated with Artemisia capillaries (HEAC) and its primary compound, scoparone, were utilized and incorporated in studying the protective effects on Carbon tetrachloride (CCl4)-induced hepatic damage in male Sprague-Dawley rats. Male Sprague-Dawley rats were randomly divided into control, CCl4, CCl4+ursodeoxycholic acid (UDCA), CCl4+silymarin, CCl4+scoparone, CCl4+HEAC, CCl4+80% ethanol extract of H. Erinaceum (HE), and CCl4+80% ethanol extract of Artemisia capillaries (AC). Each group contained eight rats supplemented with UDCA, silymarin, scoparone, HEAC, HE, and AC with continuous normal diet after CCl4 treatment. Physiological results shows control group gained weight 4.0 g day−1 and that of CCl4 group decreased 6.4 g day−1. Supplementation of UDCA, silymarin, scoparone, HEAC, HE, and AC decreased weight loss at 5.5, 4.1, 2.2, 5.5, and 4.2 g day−1, respectively. Supplementation of UDCA, silymarin, scoparone, HEAC, HE, and AC significantly decreased serum alanine aminotransferase and aspartate aminotransferase activity as well as hepatic cholesterol, low-density lipoprotein (LDL)-cholesterol, and triglycerides. Hepatic highdensity lipoprotein (HDL)-cholesterol in CCl4 group was reduced after CCl4 treatment, and supplementation of UDCA, scoparone, HEAC, HE, and AC increased HDL-cholesterol level to that of control level. Atherogenic index and cardiac risks factor in CCl4 group increased after CCl4 treatment, and supplementation of tested compounds reduced both parameters. Taken together, HEAC and scoparone exerted protective effect against CCl4-induced liver injury by attenuating hepatic lipid depots and reducing oxidative stress.
    Journal of the Korean Society for Applied Biological Chemistry 54(4). · 0.43 Impact Factor
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    ABSTRACT: The fungicidal activities against phytopathogenic fungi of two aminothiazole compounds of N-[4-(4-fluoro)phenyl-2-aminothiazol-5-yl]pyrimidin-2-yl-N-subst. phenylamine (V-1, V-2) have been determined and these two compounds were used as the leading compounds in this study as V-1 for N-[4-(4-fluoro)phenyl-2-aminothiazol-5-yl]pyrimidin-2-yl-N-(3-hydroxymethyl)phenylamine and V-2 for N- [4-(4-fluoro)phenyl-2-aminothiazol-5-yl] pyrimidin-2-yl-N-3-(l-hydroxyethyl)phenylamine. Further syntheses of these two compounds, V-l and V-2, were conducted by reacting them with three functional groups, 2-(N-ethoxycarbonyl)piperidin-4-yl, 2-piperidin-4-yl, and 2-(N-methyl)-piperidin-4-yl-thiazole. From this scheme, 21 compounds were newly synthesized and their structures were confirmed by 1H-NMR-spectrum. The fungicidal activities of all the synthesized compounds against Phytophthora capsici were examined using the whole plant method. While the EC50 value of the commercial fungicide dimethomorph was 4.26 mM, that of IX-3g on P. capsici was 1.03 mM. Among the 21 chemicals, IX-3g showed the most potential antifungal activity in vivo. Therefore, IX-3g may be considered as a potential candidate for the control of phytopathogenic diseases characterized by P. capsici infection, and further studies will be conducted on the mode of action IX-3g.
    Journal of the Korean Society for Applied Biological Chemistry 53(2). · 0.43 Impact Factor

Publication Stats

176 Citations
171 Downloads
883 Views
9.97 Total Impact Points

Institutions

  • 2002–2013
    • Soonchunhyang University
      • • Department of Biotechnology
      • • Department of Chemistry
      Asan, South Chungcheong, South Korea
  • 2008
    • Hankyong National University
      • Institute of Ecological Phytochemistry
      Anseong, Gyeonggi, South Korea
  • 2005
    • Seoul National University
      • Department of Agricultural Biotechnology
      Seoul, Seoul, South Korea