• Archives of Pharmacal Research
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• v.22 no.3
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• pp.317-319
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• 1999

Anticomplementary activity of hederagenin and related saponins isolated from Dipsacus asper was investigated in vitro. HN saponin F (3) was most potent with $IC_{50}$ value of$ 3.7{\times}10^{-5} M$ followed by 3-O-${\beta}-D-glucopyranosyl-(1{\rightarrow} 3)-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)-{\beta}-L-arabinopyranosyl$ hederagenin $28-O-{\beta}-D-glucopyranosyl-(1{\rightarrow}6)-beta$-D-glucopyrano side (8), $3-O-{\beta}-L-arabinopyranosyl$ hederagenin $28-O-{\beta}-D-glucopyranosyl-(1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (5), dipsacus saponin A (4), and hederagenin (1) on the classical pathway (CP) of complement system, while the saponins 3-5 did not show the inhibition of hemolysis and rather increase the hemolysis on the alternative pathway (AP). However, all of C-3 monodesmosides [prosapogenin CP (2), dipsacus saponin B (6), and dipsacus saponin C (7)] evoked hemolysis directly on the erythrocytes.

• Archives of Pharmacal Research
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• v.28 no.5
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• pp.529-533
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• 2005

In the course of searching for hepatoprotective agents from natural products, six compounds were isolated from the MeOH extract of the leaves of Juglans sinensis, as guid ed by their DPPH free radical scavenging activity. The structures were determined as juglanoside B (1), quercetin 3-O-${\alpha}$-L-arabinofuranoside (avicularin, 2), quercetin 3-O-${\alpha}$-L-arabinopyranoside (guaijaverin,3), quercetin 3-O-${\alpha}$-L-rhamnopyranoside (quercitrin,4), (+)-catechin (5) and quercetin 3-O-${\beta}$- D-galactopyranoside (hyperin,6). Compounds 2-6 showed significant DPPH free radical scavenging effects. An evaluation for the hepatoprotective activity of the isolated compounds on drug-induced cytotoxicity was conducted, and compounds 1, 2, and 5 showed protective effects against nitrofurantoin-induced cytotoxicity, and compound 5 also exhibited a moderate protective effect on amiodarone-induced cytotoxicity in Hep G2 cells.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.39-46
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• 2018

Column chromatographic separation of the MeOH extract from the roots of Dicentra spectabilis yielded fourteen compounds, menisdaurin (1), menisdaurilide (2), trans-N-p-coumaroyltyramine (3), trans-N-p-feruloyltyramine (4), 4-O-feruloylquinicacid (5), chlorogenic acid (6), 3-O-feruloylquinicacid (7), ferulic acid (8), protopine (9), Kaempferol 3,7-di-O-${\beta}-{\text\tiny{D}}$-glucopyranoside (10), kaempferol 3-O-${\beta}-{\text\tiny{D}}$-glucopyranosyl-7-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranoside (11), ${\alpha}-rhamnoisorobin$ (12), astragalin (13), and nicotiflorin (14). Their structures were determined on the basis of NMR spectroscopic data. Among them, compound 1, 3-8, and 10-14 isolated from this plant were reported for the first time. The isolated compounds (1-14) were tested for nitric oxide (NO) inhibitory activity on lipopolysaccharide-stimulated RAW 264.7 cells. Compound 3, 4 and 12 significantly inhibited NO production. Moreover, Compound 3 suppressed pro-inflammatory cytokines ($TNF-{\alpha}$, $IL-1{\beta}$ and IL-6) in a dose- dependent manner. These data suggest that compound 3 possess anti-inflammatory activity and might be useful natural materials for development of anti-inflammatory agent.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.144-149
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• 2003

Extracts were obtained from the flower of Rhododendro yedoense var. poukhanense. (7 kg) in 80% aqueous MeOH and successively fractionated with solvent of EtOAc, n-BuOH and $H_2O$, successively. Silica gel and ODS column chromatographies of the EtOAc and n-BuOH fractions were repeatedly carried out by using the various solvent systems to give five terpenoids. Chemical structures of the isolated terpenoids were determined as $2{\alpha},3{\beta}-dihydroxylolean-12-ene$ (1), ursolic acid (2), grayanotoxin IV (3), grayanotoxin I (4) and grayanotoxin III (5) based on the interpretation of several spectral data including 2D-NMR such as $^1H-^1H\;COSY$, HMQC and HMBC.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.357-363
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• 2011

Recently, we found that Arthrobacter crystallopoietes N-08 isolated from soil directly produces trehalose from maltose by a resting cell reaction. In this study, the optimal set of conditions and substrate specificity for the trehalose production using resting cells was investigated. Optimum temperature and pH of the resting cell reaction were $55^{\circ}C$ and pH 5.5, respectively, and the reaction was stable for two hours at $37{\sim}55^{\circ}C$ and for one hour at the wide pH ranges of 3~9. Various disaccharide substrates with different glycosidic linkages, such as maltose, isomaltose, cellobiose, nigerose, sophorose, and laminaribiose, were converted into trehalose-like spots in thin layer chromatography (TLC). These results indicated broad substrate specificity of this reaction and the possibility that cellobiose could be converted into other trehalose anomers such as ${\alpha},{\beta}$- and ${\beta},{\beta}$-trehalose. Therefore, the product after the resting cell reaction with cellobiose was purified by ${\beta}$-glucosidase treatment and Dowex-1 ($OH^-$) column chromatography and its structure was analyzed. Component sugar and methylation analyses indicated that this cellobiose-conversion product was composed of only non-reducing terminal glucopyranoside. MALDI-TOF and ESI-MS/MS analyses suggested that this oligosaccharide contained a non-reducing disaccharide unit with a 1,1-glucosidic linkage. When this disaccharide was analyzed by $^1H$-NMR and $^{13}C$-NMR, it gave the same signals with ${\alpha}$-D-glucopyranosyl-(1,1)-${\alpha}$-D-glucopyranoside. These results suggest that cellobiose can be converted to ${\alpha},{\alpha}$-trehalose by the resting cells of A. crystallopoietes N-08.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.10
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• pp.1085-1093
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• 2010

This paper proposes a multiple filter for reduction of received signal fluctuation and enhancement of step altitude edge detection in FMCW radar altimeter. The proposed filter was composed of alpha-trimmed mean filter, frequency variation limiter, and 1/3 order static filter. Simulations by analysis of received signal show that the proposed filter provides better performance than moving average and standard median filters with error reduction. In particular, the proposed filter was improved in the ability of reducing fluctuation for ground hovering.

• Bulletin of the Korean Chemical Society
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• v.8 no.2
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• pp.79-83
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• 1987

The reduction of a series of 1-substituted benzyl-3-cyanoquinolinium ions (p-$cH_3$, H, p-Br, m-F, p-CN) by sodium borohydride has been investigated. In all cases the products from these reactions were found to be 1, 2-dihydroquinolines over 82% yields. Rates of reduction were measured in basic condition and in solvent system consisting of 4 parts of isopropyl alcohol and 1 part of water by volume. Second order rate constants were obtained for these reactions. When the ratio of [$OH^-$] to [$BH_4^-$] becomes large the observed rate constants ($K_{obs}$) decrease by a small factor. Reaction scheme and rate law are discussed. Bronsted ${\alpha}(=\frac{d\;In\;k}{d\;In\;K})$ obtained by using the value of equilibrium constant K, which was obtained previously, was not 0. Instead, a value of 0.36 was obtained which indicated that the reduction by borohydride was structure-dependent according to the Marcus formalism even though the reaction rate was close to the diffusion limit.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.7
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• pp.1563-1568
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• 2003

The introduction of invasive marine species of living things into new environments by ship's ballast water, attached to ships' hulls and via other vectors has been identified as one of the four greatest threats to the world's oceans by Global Environment Facility(GEF). Making use of the new technology of alpha-AL$_2$O$_3$ dielectric barrier layer, the strong electric-field gas discharge was introduced and obtained between micro-gap electrodes at high pressure (∼105㎩) of $O_2$ in air and $H_2O$ in seawater. The mixed air with $H_2O$ could be ionized and dissociated into large numbers of activated particles of OH, $O_2$＋, O(1D), HO$_2$ and so on, and then dissolved into the ballast water to form dissolved hydroxyl radical with the concentration of ∼20mg/L. Therefore, the invasive marine species was treated effectively through the hydroxyl radical dissolved pipeline of ballast water by strong electric -field discharge.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.591-599
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• 2015

Cercidiphyllum japonicum leaves were collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. A portion of EtOAc fraction (10 g) was chromatographed on a Sephadex LH-20 column, by the successively elution with various aqueous $MeOH-H_2O$ (1:9, fraction $1-2{\rightarrow}3:7$, fraction $3-5{\rightarrow}1:1$, fraction $6-9{\rightarrow}7:3$, fraction $10-13{\rightarrow}9:1$, fraction 14-16). Compound 2 was isolated from fraction 6 and compound 1 was separated from fraction 11 and 12. Compound 3 and 4 were purified from fraction 13. The isolated compounds were elucidated as quercetin-3-O-${\alpha}$-L-rhamnopyranoside (1), chlorogenic acid (2), quercetin-3-O-${\alpha}$-L-arabinofuranoside (3) and quercetin-3-O-${\beta}$-D-xylopyranoside (4) by the spectral and literature data, and by comparison with the authentic samples. These compounds were reported, for the first time, from the extracts of C. japonicum leaves. Also chlorogenic acid (2) has never been reported before in domestic tree species and can be used as an index compound for C. japonicum.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1086-1090
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• 2006

The chromatographic separation of the MeOH extract from the twigs of Acer tegmentosum led to the isolation of ten phenolic compounds. The structures of these compounds were determined using spectroscopic methods as 3,7,3',4'-tetramethyl-quercetin (1), 5,3'-dihydroxy-3,7,4'-trimethoxy flavone (2), 2,6-dimethoxy-p-hydroquinone (3), (-)-catechin (4), morin-3-O-${\alpha}$-L-lyxoside (5), p-hydroxy phenylethyl-O-${\beta}$-D-glucopyranoside (6), 3,5-dimethoxy-4-hydroxy phenyl-1-O-${\beta}$-D-glucoside (7), fraxin (8), 3,5-dimethoxy-benzyl alcohol 4-O-${\beta}$-D-glucopyranoside (9) and 4-(2,3-dihydroxy propyl)-2,6-dimethoxy phenyl ${\beta}$-D-glucopyranoside (10). The compounds were examined for their cytotoxic activity against five cancer cell lines. Compound 3 exhibited good cytotoxic activity against five human cancer cell lines with $ED_{50}$ values ranging from $1.32\;to\;3.85\;{\mu}M$.