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Polyacetylene Compounds from Panax ginseng C.A. Meyer (인삼의 Polyacetylene 화합물)

  • Shim Sang Chul;Chang Suk-Ku
    • Proceedings of the Ginseng society Conference
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    • 1988.08a
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    • pp.122-128
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    • 1988
  • Several major polyacetylene compounds were isolated from the petroleum-ether fraction of fresh Korean ginseng roots through solvent fractionation. partition and silica gel column chromatography. Further separation of acetylenic compounds was accomplished by bonded normal phase HPLC utilizing a moderately nonpolar microparticulate column. The preparative separation for the various spectral measurements was carried out by low pressure preparative liquid chromatography. The chemical structure of these polyacetylenes separated was determined by UV. IR/FTIR. 1H NMR. mass spectral and elemental analysis. These are identified to be heptadeca-1-en-4.6-diyn-3.9.l0.-triol [1] heptadeca-1.9-dien-4.6-diyn-3-ol. heptadeca-1.8-dien-4.6-diyn-3.10-diol and the 4th was denatured polyacetylene. heptadeca-1.4-dien-6.8-diyn-3.10-diol. Two different p-substituted benzoates of panaxynol were synthesized for the determination of exciton chirality. The circular dichroism spectra in the UV region show that panaxynol p-bromobenzoate and p-dimethyl-aminobenzoate constitute negative exciton chirality [2]. Isolated major polyacetylene compounds were irradiated in aerated solution with 300 nm UV light to obtain the oxidized product at the allylic alcohol center to corresponding carbonyl compounds such as heptadeca-1-en-4.6-diyn-9.10-diol-3-one and heptadeca-1.9-dien-4.6-diyn-3-one. These photooxidation compounds have en-on-diyne chromophore and undergo nucleophilic addition reaction with methanol to yield βmethoxy carbonyl compounds such as heptadeca-9-en-4.6-diyn-1-methoxy-3-one and heptadeca-4.6-diyn-1-methoxy-9.10-diol-3-one.

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Modulation of Cell Cycle Regulators by Sulforaphane in Human Mepatocarcinoma HepG2 Cells (HepG2 인체간암세포의 세포주기조절인자 발현에 미치는 sulforaphane의 영향)

  • Bae, Song-Ja;Kim, Gi-Young;Yoo, Young-Hyun;Choi, Byung-Tae;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.16 no.7 s.80
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    • pp.1235-1242
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    • 2006
  • Sulforaphane, an isothiocyanate derived from hydrolysis of glucoraphanin in broccoli and other cruciferous vegetables, was shown to induce phase II detoxification enzymes and inhibit chemically induced mammary tumors in rodents. Recently, sulforaphane is known to induce cell cycle arrest and apoptosis in human canter cells, however its molecular mechanisms are poorly understood. In tile present study, we demonstrated that sulforaphane acted to inhibit proliferation and induce morphological changes of human hepatocarcinoma HepG2 cells. Treatment of HepG2 cells with 10μMor15μM sulforaphane resulted in significant G2/M cell cycle arrest as determined by DNA flow cytometry. Moreover, 20μM sulforaphane significantly induced the population of sub-G1 cells suggesting that sulforaphane induced apoptosis. This anti-proliferative effect of sulforaphane was accompanied by a marked inhibition of ryclin A, cyclin 31 and Cdc2 protein. However, the levels of tumor suppressor p53 and Cdk inhibitor p21 mRNA and protein expression were significantly increased by sulforaphane treatment in a concentration-dependent manner. Although further studies are needed, the present work suggests that sulforaphane may be a potential rhemoprevetiveichemotherapeucc agent for the treatment of human cancer cells.

Sanguinarine Increases Sensitivity of Human Gastric Adenocarcinoma Cells to TRAIL-mediated Apoptosis by Inducing DR5 Expression and ROS Generation (AGS 인체 위암세포에서 DR5의 발현 및 ROS 생성의 증가를 통한 sanguinarine과 TRAIL 혼합처리의 apoptosis 유도 활성 촉진)

  • Lee, Taek Ju;Im, Yong Gyun;Choi, Woo Young;Choi, Sung Hyun;Hwang, Won Deok;Choi, Yung Hyun
    • Journal of Life Science
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    • v.24 no.9
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    • pp.927-934
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    • 2014
  • Sanguinarine, a benzophenanthridine alkaloid originally derived from the root of Sanguinaria canadensis, has been shown to possess antimicrobial, antioxidant, and anti-cancer properties. Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is known to induce apoptosis in cancer cells, but not most normal cells and has shown efficacy in a phase 2 clinical trial, development of resistance to TRAIL by tumor cells is a major roadblock. Our previous study indicated that treatment with TRAIL in combination with subtoxic concentrations of sanguinarine sensitized TRAIL-mediated apoptosis in TRAIL-resistant human gastric carcinoma AGS cells; however, the detailed mechanisms are not fully understood. In this study, we show that sanguinarine sensitizes AGS cells to TRAIL-mediated apoptosis as detected by MTT assay, agarose gel electrophoresis, chromatin condensation and flow cytometry analysis. Combined treatment with sanguinarine and TRAIL effectively induced expression of death receptor (DR) 5 but did not affect expression of DR4 and mitogen activated protein kinases signaling molecules. Moreover, the combined treatment with sanguinarine and TRAIL increased the generation of reactive oxygen species (ROS); however, N-acetylcysteine, ROS scavenger, significantly recovered growth inhibition induced by the combined treatment. Taken together, our results indicate that sanguinarine can potentiate TRAIL-mediated apoptosis through upregulation of DR5 expression and ROS generation.

Expression of MEK1 Fusion Protein in Yeast for Developing Cell Based Assay System, a Major Substrate of LeTx (Yeast내에서 MEK1 융합 단백질 발현 및 Lethal Factor 활성 검증)

  • Hwang, Hye-Hyun;Kim, Joung-Mok;Choi, Kyoung-Jae;Park, Hae-Chul;Han, Sung-Hwan;Chung, Hoe-Il;Koo, Bon-Sung;Park, Joon-Shik;Yoon, Moon-Young
    • Korean Journal of Microbiology
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    • v.42 no.3
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    • pp.195-198
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    • 2006
  • Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.

A Basic Study on the Production of Sm2Fe17Nx System Rare Earth Permanent Magnet by the Reduction and Diffusion(I) - Production of Alloy Powder of Sm2Fe17 Intermetallic Compound - (환원.확산법에 의한 Sm2Fe17Nx 계 희토류 영구자석의 제조에 관한 기초연구(제 1보) -Sm2Fe17금속간화합물 합금분말의 제조-)

  • Song, Chang-Bin;Choo, Tong-Rae
    • Korean Journal of Materials Research
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    • v.8 no.8
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    • pp.720-725
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    • 1998
  • As a basic study on the production of Sm2Fe17Nx system rare earth permanent magnet by the reduction and diffusion(R- D) process, firstly the reduction reaction of Sm2O3 by metallic Ca and diffusion of Sm into Fe powder was investigated for the production the Sm2Fe17intermetallic compound. We concluded that the former case was very rapidly completed under the high temperature greater than 1000C and the latter case of completion of diffusion reaction of Sm into the center of Fe powder(perfect homogenization condition) was required through 3h R- D reaction at 1100C and identified as a rate determining step(RDS) on the whole reaction. Though SmFe2,SmFe3, and Sm2Fe17phases in the growth of phases of intermetallic compound in the Sm - Fe binary system were obseved below 1000C, but only Sm2Fe17phase was observed at lIOOC. Oxygen and Ca contents of the final sample in this work were 0.72wt% and O. 11 wt% respectively.

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The Influence of O2 Partial Pressure on Soft Magnetic Properties of As-deposited Fe-Sm-O Thin Films (산소분압에 따른 Fe-Sm-O계 박막의 연자기적 성질)

  • Yoon, T.S.;Cho, W.S.;Koo, E.S.;Li, Ying;Park, J.B.;Kim, C.O.
    • Korean Journal of Materials Research
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    • v.10 no.11
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    • pp.755-759
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    • 2000
  • The influence of O2partial presure on saturation magnetization, coercivity and effective permeability(0.5~100MHz) of as-deposited Fe-Sm-O thin films, which were fabricated by RF magnetron reactive sputtering method, were investigated. The nanocrystalline Fe(sub)83.4Sm(sub)3.4O(sub)13.2 thin film fabricated at O2partial pressure of 5% exhibits the best magnetic softness with saturation magnetization of 18kG, coercivity of 0.82 Oe and effective permeability about 2,600 at 0.5~100MHz. α-Fe grain size is decreased with increasing O2partial pressure. In case of O2partial pressure of 10%, it is observed that FeO compound is formed and soft magnetic properties are decreased. The electrical resistivity of Fe-Sm-O thin films were increased with increasing O2partial pressure, the electrical resistivity of Fe(sub)83.4Sm(sub)3.4O(sub)13.2 thin film with the best soft magnetic properties was 130 μΩcm. Therefore, It is assumed that the good soft magnetic properties of Fe(sub)83.4Sm(sub)3.4O(sub)13.2 thin film results from high electrical resistivity and decreasing α-Fe grain size due to precipitation of Sm-Oxide phase.

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Experimental and FEMLAB Simulation Study of Ibuprofen Racemate Separation in HPLC (Ibuprofen Racemate의 HPLC 분리실험과 FEMLAB 전산모사 연구)

  • Lee, Eun;Chang, Sang-Mork;Kim, Jong-Min;Kim, Woo-Shick;Kim, In-Ho
    • KSBB Journal
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    • v.21 no.3
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    • pp.224-229
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    • 2006
  • FEMLAB is a powerful interactive environment for modeling, solving all kinds of scientific and engineering problems based on partial differential equations(PDEs). Separation process of chiral compound in HPLC columns was simulated by FEMLAB. To study change of elution profile with isotherm models, non-competitive and competitive Langmuir adsorption isotherm were adopted. Separated material was (R, S)-ibuprofen [(R, S)-2-(4-isobutyl phenyl) propionic acid], an anti-inflammatory agent, which retain the pharmacological activity in the (S)-(+)-enantiomer. Sample concentrations were changed from 0.5 mg/ml to 2.0 mg/ml at a flow rate of 1 ml/min and flow rate varied from 1 ml/min to 3 ml/min at an ibuprofen concentration of 2.0 mg/ml and 20μl of injection volume. Simulated results were well fitted with experimental data.

Study of an Applicability of an Urban Design Method Using Artificial Life Theory (인공생명이론을 이용한 도시설계방법의 적용 가능성에 대한 연구)

  • Lim, Myunggu;Kim, Kyoontai
    • Korean Journal of Construction Engineering and Management
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    • v.19 no.4
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    • pp.93-101
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    • 2018
  • A city is like a living organism that is born, grows and become extinct within an ecosystem. In recent years, more and more cities have been planned by designers rather than spontaneously growing over time. This planning means that if a city is not appropriately designed at the beginning, it is very hard to fix or adjust it later. A poor urban design inconveniences many people, and forces them to adjust to it. For this reason, it is important to design a city as optimally as possible at the design phase. One of the reasons why a city is not designed optimally is complexity. Previous urban design methods have attempted to resolve the complexity by using a top-down problem-solving method based on the experience and knowledge of the urban planner. However, such an approach does not have the organic characteristics of a bottom-up problem-solving method of an artificial life, based on the creation principle of the ecosystem. Therefore, in this study the general principle of artificial life, which can provide a solution to the bigger problems that accumulate as a result of the solutions to small units of problems, is adopted. This enables us to draw various urban design alternatives, and it proves that the alternatives, despite being drawn through a limited modeling method, have almost no differences from those designed by an expert, and its possibilities of future development has also been verified.

A Study on the Probability of BLEVE of Above-ground LP Gas Storage Tanks Exposed to External Fire (지상식 LPG 저장탱크의 외부화재에 의한 BLEVE 가능성 해석)

  • Lee Seung-Lim;Lee Young-Soon
    • Journal of the Korean Institute of Gas
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    • v.7 no.1 s.18
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    • pp.19-23
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    • 2003
  • The purpose of this thesis is to investigate the BLEVE probability of LP gas storage tanks which are relatively more dangerous, by the deductive calculating method using the results of Birk's pilot tank test and the required heat capacity of BLEVE. The result that BLEVEs can occur in only above 43.68 percent of liquid filling level under 600C of tank pate temperature and 53C of inner liquid temperature, was obtained and will be useful for preventing the BLEVE of LP gas storage tanks in fire sites. In addition, this research showed conditions of external leak and fire causing BLEVE, based on 15ton capacity of LP gas tank which has the same specifications as those in Puchon LP gas filling station accident. The result of the calculation is that the minimum pool fire conditions of BLEVE are above 7.2mm equivalent diameter under a liquid release condition and above 17.6mm equivalent diameter under a two-phase release condition. In the end, the result of calculating the pool size corresponding the above conditions using EFFECTS version 2.1, concludes that a minimum of 3.3 meters of diameter and 10.4 meters of height should be needed for BLEVE outbreak.

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Effects of a Mixture of Eugenol, Thymol and Malate on Growth Performance, Beef Quality and Liver Function in Hanwoo Finishing Steers Fed a High-Concentrate Diet

  • Kim, Do-Hyung;Kim, Kyoung-Hoon;Choi, Chang-Weon;Kwon, Eung-Gi;Hong, Seong-Koo;Lee, Sang-Cheol;Seol, Yong-Joo;Yeo, Joon-Mo;Kim, Wan-Young;Keum, Jong-Soo;Lee, Sung-Sill;Oh, Young-Kyoon
    • Journal of Animal Science and Technology
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    • v.52 no.6
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    • pp.505-511
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    • 2010
  • Thirty six Hanwoo steers (average BW, 564.5±25.7kg; average age, approximately 23 months) were used to evaluate the effects of a mixture of eugenol (14%), thymol (1%) and malate (85%) on growth performance, beef quality and liver function in Hanwoo finishing steers fed a high-concentrate diet. A feeding trial was conducted for 7 months in National Agricultural Cooperative Federation farm located in Anseong, Korea. Steers were assigned randomly to one of three treatments: control (without additive supplementation), treatment 1 (0.05% additive of concentrate), treatment 2 (0.1% additive of concentrate). The results of this study showed that initial and final BW averaged 564 and 755 kg, respectively, and BW gain was significantly higher (P<0.05) for steers fed the additive mixture than for those fed no mixture (0.78 and 0.79 vs. 0.69 kg/d, respectively). Serum aspartate aminotransferase in the T2 treatment was decreased during the 24 to 31 months of age. Although supplementation of additives resulted in no substantial effect on carcass characteristics, it had a potential effect to improve feed efficiency and AST concentration in Hanwoo finishing steers fed a high-concentrate diet. In conclusion, a mixture of eugenol, thymol and malate has shown promise in improving feed efficiency and liver function in the finishing phase of Hanwoo steers.