• KOMUNHWA
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• no.66
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• pp.87-112
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• 2005

Stain removal on ivory has been, for a long time, considered an undesirable treatment in conservation field because ivory is hygroscopic and anisotropic, having different physical properties in different directions. Cyclododecane, which sublimes at room temperature, has been investigated for its use in conservation field since 1995, as a reversible temporary consolidant, sealing agent or coating, water repellent, and barrier layer. This research aims to remove stains on ivory, temporarily protecting the none-stained area or painted area from methanol, acetone or the aqueous cleaning system using cyclododecane as a hydrophobic sealing agent. This research also aims to obtain information regarding whether cyclododecane can be safely and effectively used on archaeological wet ivory. Melted cyclododecane and saturated solutions of cyclododecane in mineral spirits, and hexanes were applied to ivory samples. Application methods, working properties of cyclododecane on ivory, and effect of cyclododecane coating on moisture content of wet ivory were evaluated. The sealing layer formed by molten cyclododecane or by saturated cyclododecane solution in hexane or saturated cyclododecane solution in mineral spirits did not form a secure contact with the surface of the highly polished ivory. The sealing formed with two different layers, in which saturated cyclododecane solution in hexane was applied initially and then molten cyclododecane was applied over the first layer, was found to securely protect the painted area. When the wet samples were kept in 100% RH environments for a month, active mold growths were observed except in the samples sealed with molten cyclododecane. In conclusion, cyclododecane was an efficient hydrophobic sealing agent to protect painting area while cleaning stains on ivory. It also prevented mold growing on wet ivory and wet bone. Evenness of cyclododecane film on ivory will be determined in UV light. Analytical techniques will include visual observation, polarized light microscopy, Scanning Electron Microscope, and Gas Chromatography.

• Analytical Science and Technology
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• v.7 no.1
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• pp.25-31
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• 1994

As for analytes which did not represent the differences of the selectivity on the stationary and mobile phase, secondary chemical equilibrium theory was applied to study pH effects on the separation of alkylphenols. Mobile phase was consisted of an aqueous sodium carbonate-bicarbonate buffer and acetonitrile. The maximum selectivity for adjacent peak pairs was predicted from those values of $k^{\prime}_{HA}/k^{\prime}_{A-}$ and ${\Delta}pK$. The optimum pH determined by this method was 11.18 pH and solvent selectivity were considered at the same time to invoke the full range of selectivity effects possible for separations. Quaternary mixture composed of methanol, acetonitrile, tetrahydrofuran and water was adjusted to optimum pH 11.18. As the statistical simplex technique of an overlapping resolution map (ORM) was used to predict the optimized solvent system. The optimum solvent, which gives complete separation of alkylphenols, was determined as follws MeOH : ACN : THF = 14.4 : 81.8 : 2.8.

• Natural Product Sciences
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• v.3 no.2
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• pp.81-88
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• 1997

NAD(P)H:quinone reductase (QR) is one of the protective phase II enzymes against toxicity that accomplishes the capacity of detoxification by modulating the effects of mutagens and carcinogens. The detoxification mechanism is that quinone reductase promotes the 2-electron reduction of quinones to hydroquinones which are less reactive. This study is to search new inducers of quinone reductase from natural products, which can be used as cancer chemopreventive agents. Plant extracts were evaluated by using quinone reductase generating system With Hepa 1c1c7 murine hepatoma cell lines for enzyme inducing properties and crystal violet staining method for the measurement of cytotoxicity provoked. We have tested approximately 106 kinds of natural products after partition into n-hexane, ethyl acetate and aqueous layers from 100% methanol extracts of natural products. The ethyl acetate fractions of Vitex rotundifolia $(fruits,\;2FC:\;12.7\;{\mu}g/ml)$, Cnidium officinale $(aerial\;parts,\;2FC:\;10.5\;{\mu}g/ml)$, Chrysanthemum sinese $(flowers,\;2FC:\;17.4{\mu}g/ml)$ and the hexane fractions of Angelica gigas $(roots,\;2FC:\;13.2\;{\mu}g/ml)$, Smilax china $(roots,\;2FC:\;l1.9\;{\mu}g/ml)$, Sophora flavescens $(roots,\;2FC:\;16.3\;{\mu}g/ml)$ revealed the significant induction of quinone reductase in a murine hepatic Hepa 1c1c7 cell culture system.

• Korean Journal of Pharmacognosy
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• v.37 no.2 s.145
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• pp.110-115
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• 2006

Melittia inouei (Yuri Nabang) larvae are used as a crude drug in East Asia for treating stomach cancer and inflammation, and currently reared as a pharmaceutical insect in Jejudo, Korea. This study evaluated the immuno-modulating activity of these extracts, by determining the level of, cytokine production from mouse splenocytes stimulated with the extracts. The Melittia inouei larvae extracts did not induce the splenocyte proliferation. On the other hand, they stimulated the splenocytes to produce cytokines such as $TNF-{\alpha}$, whereas they did not stimulate IL10, IL12 or $IFN-{\gamma}$. The aqueous portion of its plant (Tri-chosanthis kirilowii) extract (sap) was found to be a potent inducer of NO production from the CPAE cells. However, it showed weak inhibitory effects on vascular endothelial growth factor (VEGF) production from splenocytes. These data suggests that a Melittia inouei larvae extract immune modulatory activity in cytokine prodcutions such as $TNF-{\alpha}$ and VEGF which might be related its anticancer effect.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.245-252
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• 1993

To investigate a simple and rapid screening method for photosynthetic inhibitory herbicides, responses of tobacco(Nicotiana tabacum L.) and liverwort(Marchantia polymorpha L.) PA(photoautotrophic) cells to various commercial herbicides with different modes of action and leaf extracts of four weed species were compared. PET (photosynthetic electron transport) inhibitory type of herbicides has greater inhibitory effect in liverwort photoautotrophic cells than the photomixotrophic and heterotrophic cultured cells. Similary, PET inhibitory type of herbicides inhibited the oxygen evolution more in liverwort PA cells than the other type of herbicides. Based on oxygen evolution, 60% inhibition was observed by the 10% aqueous extracts of Polygonum hydropiper, while there was 100% inhibition by the 10% methanol extracts of Polygonum hydropiper. This assay gave well correlated results to the Hill reaction data using isolated thylakoids. Thus liverwort photoautotrophic cells might be suitable materials for rapid screening method for photosynthetic inhibitory herbicides.

• Journal of Applied Biological Chemistry
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• v.58 no.2
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• pp.109-112
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• 2015

Fruits of Rhus parviflora were extracted with 80% aqueous methanol (MeOH), and the concentrated extract was partitioned using ethyl acetate (EtOAc), n-butanol (n-BuOH), and $H_2O$, successively. Purification of EtOAc fraction led to isolation of fifteen polyphenols of which structures were identified by spectroscopic methods including 2D-NMR. Most compounds apart from compound 10 inhibited low density lipoproteinoxidation within $IC_{50}$ value of $10{\mu}M$. Among compounds, taxifolin (2), quercetin 3-O-${\alpha}$-L-rhamnopyranoside (13), agathisflavone (5) sulfuretin (4), and aureusidin (3) showed $IC_{50}$ values 0.9, 0.8, 5.8, 2.9, and $2.4{\mu}M$ which were of highly significant in comparison positive control butylated hydroxytoluene with $IC_{50}$ value of $2.1{\mu}M$. The results indicate fruits of R. parviflora as a source of antihypercholesterolemic compounds.

• Journal of Applied Biological Chemistry
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• v.56 no.4
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• pp.213-217
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• 2013

Phytochemical studies on the leaves of Ailanthus altissima (Simaroubaceae) have not been reported previously. Thus, the authors isolated and identified secondary metabolites from A. altissima. Dried and powdered leaves were extracted with 80% aqueous methanol, and the concentrated extract was successively partitioned with ethyl acetate, n-butanol, and water. Four flavonoids were isolated from the ethyl acetate fraction through repeated silica gel and octadecyl silica gel column chromatography. Spectroscopic data including NMR, MS, and IR allowed for identification of the chemical structures as quercetin (1), afzelin (2), quercitrin (3), and isoquercitrin (4). This is the first report of the isolation of these compounds from A. altissima. The four isolated flavonoids 1-4 as well as solvent fractions (ethyl acetate, n-butanol, and water), were evaluated for DPPH radical scavenging activity.

• Journal of Pharmaceutical Investigation
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• v.35 no.1
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• pp.51-55
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• 2005

A high-performance liquid chromatographic method was employed for the determination of bumetanide in human plasma. After addition of internal standard (IS, naproxen) and acidification of the plasma with 1 M hydrochloric acid, the drug and IS were extracted into dichloromethane. The organic phase was back-extracted into 1 M sodium bicarbonate solution and 50 ${\mu}l$ of the aqueous phase was injected onto a reversed-phase C18 column with a mobile phase consisting of methanol: water: glacial acetic acid = 65 : 35 : 1. The samples were detected utilizing a fluorescence detector (excitation wavelength 235 nm, emission wavelength 405 nm). The method was specific and validated with a lower limit of 5 ng/mL. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification. The applicability of the method was demonstrated by analysis of plasma after oral administration of a single 2 mg dose to 24 healthy subjects. From the plasma bumetanide concentration vs. time curves, the mean AUC was $246.5{\pm}73.8\;ng{\cdot}hr/mL$ and $C_{max}$ of $132.1{\pm}40.9$ ng/mL reached 1.2 hr after administration. The mean biological half-life of burnet ani de was $1.1{\pm}0.2$hr. Based on the results, this simple and validated assay method could readily be used in any pharmacokinetic or bioequivalence studies using humans.

• Journal of the Korean Wood Science and Technology
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• v.34 no.4
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• pp.76-82
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• 2006

The dried ground needles (2.0 kg) of Chamaecyparis pisifera (Sieb. et Zucc.) Endlicher were extracted with acetone-$H_2O$ (7:3, v/v), concentrated, and fractionated with a series of n-hexane, methylene chloride, ethyl acetate and water on a separation funnel. Each fraction was freeze dried, then a portion of ethyl acetate soluble powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-n-hexane mixture as eluents. The isolated compounds were identified by cellulose TLC, $^1H$-, $^{13}C$-NMR, COSY, HETCOR, FAB and EI-MS. (+)-catechin, taxifolin-3-O-${\beta}$-D-xylopyrano-side, quercetin-3-O-${\alpha}$-L-rhamnopyranoside were isolated from the ethyl acetate soluble fraction of Chamaecypairs pisifera needle. Antioxidative tests on the isolated compounds indicated that all of the compounds showed similar values to ${\alpha}$-tocopherol and BHT as controls.

• Journal of the Korean Chemical Society
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• v.43 no.6
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• pp.656-662
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• 1999

We have obtained retention data of benzene, toluene, ethylbenzene, phenol, and acetophenone at 25, 30, 35, 40, 45 and 50 $^{\circ}C$ in 30/70, 40/60, 50/50, 60/40, 70/30, and 80/20 (v/v %) methanol/water eluents using a $C_18$ phase with a high ligand density. We drew van't Hoff plots from the data, and computed enthalpies and entropies of solute transfer from the mobile to the stationary phase. The cavity formation effect was found the major factor that governs the solute distribution between the mobile and stationary phases. The hydrophobic effect became significant in highly aqueous mobile phases. We also concluded that the Shodex C18-5B stationary phase was a polymer-like phase with a high ligand density, and followed a partially adsorption-like mechanism.