• Proceedings of the PSK Conference
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• 2003.04a
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• pp.253.1-253.1
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• 2003

Twenty-seven N,N',N"-trisubstituted thiourea derivatives were prepared. Among them, 1- [3-(4'-hydroxy-3'-methoxy-phenyl)-propyl] -1,3-diphenethyl-thiourea (81, IC$\sub$50/= 0,32 $\mu\textrm{m}$), showed 2-fold higher antagonistic activity than that of capsazepine (3, IC$\sub$50/= 0,65 $\mu\textrm{m}$) against the vanilloid receptor in a Ca$\^$2+/ -influx assay.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.168.1-168.1
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• 2003

We show that panaxadiol (PD), a ginseng saponin with a dammarane skeleton, selectively interferes with the cell cycle in human cancer cell lines. PD inhibited DNA synthesis in a dose-dependent manner with $IC_{50}$ values ranging from 0.8 $\mu$M-1.2 $\mu$M in SK-HEP-1 cells and HeLa cells. PD-treated cells were arrested at G1/S phase, shich coincided well with decreases in Cyclin A-Cdk2 activity, but not in Cyclin E-Cdk2 and Cdc2 activities. The intracellular levels of $p21^{WAF1/CIP1}$ were significantly and selectively elevated in a dose and time-dependent manners in PD-treated HeLa cells. (omitted)

• Journal of the Korean Chemical Society
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• v.53 no.1
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• pp.34-41
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• 2009

A new series of hydrazone derivatives were synthesized from 4-(2-chloroethyl)semicarbazide and their antiproliferative activity against human brain (U251) and liver (Hepg2) carcinoma cell lines were evaluated. The hydrazone compounds are benzaldehyde (2a-2g), acetophenone (3a-3f), and 3-formylindole derivatives (4a-4d). Among the acetophenone derivatives, 3e (p-methoxy substituted) and 3f (p-nitro substituted) showed the highest cytotoxic activity against Hepg2 cell line (I$C_{50}$ = 6 and 8 $\mu$g/ml, respectively). Among the 3-formylindole derivatives, 4a (hydrazone of 3-formylindole itself) showed a pronounced cytotoxic activity against both U251 (I$C_{50}$ = 21 $\mu$g/ml) and Hepg2 (I$C_{50}$ = 7 $\mu$g/ml).

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.333-338
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• 2015

The objective of this study was to investigate the whitening effect of Salvia miltorrhiza Bunge water extract (SM-W) in human epidermal melanocyte (HEM). Mushroom tyrosinase inhibitory effect of SM-W was approximately 42% at $1,000{\mu}g/mL$. The HEM cellular tyrosinase and melanin synthesis inhibition activity were 26 and 25% at $5{\mu}g/mL$, respectively. Whitening related proteins and mRNAs including tyrosinase, tyrosinase related protein 1 (TRP-1) and TRP-2, and microphthalmia associated transcription factor were reduced by SM-W treatment. In addition, the cAMP expression inhibitory effect of SM-W was decreased by 41% at $5{\mu}g/mL$ concentration. These results indicated that Salvia miltorrhiza Bunge could be used to the possible utilization of functional cosmetic ingredients by confirming whitening activity related with melanin content.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.3
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• pp.139-144
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• 2003

Nickel fine powders were prepared from nickel chloride aqueous solution containing ethanol as an organic solvent, and their oxidation behaviors were investigated. The reduction reaction by hydrazine from nickel chloride aqueous solution containing ethanol depend on reaction temperature. The reduction reaction time by hydrazine decreased with the increase of reaction temperature. By controlling reaction temperature, the products could be obtained spherical particles in the range of 0.1 $\mu\textrm{m}$~1.0 $\mu\textrm{m}$. Also, As reaction temperature increased from $40^{\circ}C$ to $80^{\circ}C$, the particle size slightly increased and had a broad size distribution owing to the presence of the coarse particles. The mean particle size and specific surface area of nickel powders prepared at $60^{\circ}C$ were 0.3 $\mu\textrm{m}$ and 31.8 $\m^2$/g, respectively. Weight loss of the powders at $300^{\circ}C$ was due to composition of $_Ni(OH)2$. In case of heat treatment at $200^{\circ}C$ in air, oxidation resistance of nickel powders was remarkable than that of as-synthesized.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.4
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• pp.393-402
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• 1997

In the present study, we characterized the angiotensin II (AII)-induced relaxations in the phenylephrine-precontracted rabbit mesenteric arteries with endothelium. 1) AII-induced relaxation was consistently observed in the rabbit mesenteric arteries with and without endothelium, but not in the aortic segment with endothelium. 2) AII-induced endothelium-dependent relaxation was markedly inhibited by $N^w-nitro-L-arginine$ (L-NNA, $100\;{\mu}M$), methylene blue ($10\;{\mu}M$) and LY83583 ($10\;{\mu}M$), respectively. 3) Inhibition of cyclooxygenase with indomethacin ($10\;{\mu}M$) strongly decreased the vasorelaxant response to AII irrespective of the presence of endothelium. 4) 7-Ethoxyresorufin ($1\;{\mu}M$) and clotrimazole ($1\;{\mu}M$), inhibitors of cytochrome P-450-dependent arachidonic acid metabolism, greatly attenuated the vasodilator response to AII. 5) Carbacyclin, arachidonic acid and prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$) caused concentration-dependent relaxations in the mesenteric artery with endothelium, which were inhibited by L-NNA and methylene blue. 6) AII and $PGF_{2{\alpha}}$ significantly stimulated cyclic GMP formation in the mesenteric arteries with endothelium, which was inhibited by L-NNA and methylene blue, respectively. 7) AII enhanced synthesis of $PGF_{2{\alpha}}$ and 6-keto $PGF_{1{\alpha}}$ from the arterial segments with endothelium, which was inhibitable by indomethacin, but not by L-NNA. In conclusion, the vasorelaxant responses to AII of the rabbit mesenteric artery with endothelium are subserved by arachidonic acid and its metabolites produced via activation of cyclooxygenase and cytochrome P-450 enzyme as well as by nitric oxide.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.519-523
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• 2017

We investigated the applications of functional materials through the examination of a variety of physiological activities of Ipomoea aquatica extract. I. aquatica extract showed low cytotoxicity against murine melanoma B16F10 cells. At concentrations that exerted little or no cytotoxicity to the cells, I. aquatica extract showed high DPPH radical scavenging activity ($ID_{50}$, $7.84{\mu}g/mL$), inhibited tyrosinase activity ($ID_{50}$, $106.56{\mu}g/mL$), and decreased melanin content ($ID_{50}$, $41.75{\mu}g/mL$). The treatment of B16F10 cells with I. aquatica extract suppressed the protein expression of tyrosinase in a dose-dependent manner. These findings suggested that I. aquatica extract inhibited melanin synthesis in murine melanoma B16F10 cells through the suppression of intracellular tyrosinase expression, as well as the simultaneous direct inhibition of tyrosinase activity. Additionally, I. aquatica extract promoted the expression of involucrin, which is related to skin barrier protection. These results indicate that I. aquatica extract may be an appropriate material for the improvement of skin barrier function.

• YAKHAK HOEJI
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• v.35 no.6
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• pp.497-503
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• 1991

Six novel 5-substituted-1-[2-(3-methoxy-2-hydroxyphenyl)-1-methoxyethyl]uracils 2a-f were prepared by condensation of 2,4-bis(trimethylsilyloxy)-5-substituted uracils with 2,7-dimethoxy-2,3-dihydrobenzofuran (9) in the presence of Lewis acid. The 2,3-dihydrobenzofuran derivative 9 was obtained by intramolecular acetalization of 2-acetoxy-3-methoxyphenyl acetaldehyde (8) which was synthesized by oxidative cleavage of 1-allyl-2-acetoxy-3-methoxybenzene (7) using osmium tetroxide followed by $NaIO_4$. Compounds 2a-f were evaluated for in vitro antiviral activity against HSV-1, HSV-2 and HRV. None of these compounds showed activity with $ID_{50}$ values up to $100\;{\mu}g/ml$ except for 5-chlorouracil derivative 2d which exhibited antiviral activity against HSV-1 with $ED_{50}$ $30\;{\mu}g/ml$. In the antitumor activity against L1210 and P388 leukemia cell lines, 2d showed activity with $ID_{50}$ values of $14\;{\mu}g/ml$ and $11.6\;{\mu}g/ml$, and 2c with $ID_{50}$ values of $22.9\;{\mu}g/ml$ and $8.8\;{\mu}g/ml$, respectively.

• Resources Recycling
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• v.18 no.2
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• pp.56-61
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• 2009

The dissolution of domestic aluminum hydroxide of 99.7% purity has been performed with mineral and organic acid prior to the synthesis of aluminum compounds from aluminum solution. Mean particle size of aluminum hydroxide used in the work was $14.4{\mu}m$, $22.9{\mu}m$ and $62.3{\mu}m$, respectively and the effect of reaction temperature, concentration of acid and reaction time on the dissolution of aluminum hydroxide has been examined. As a result, the dissolution of aluminum hydroxide was increased with the concentration of HCl and more than 70% dissolution was obtained with 5 mole/l HCl at $70^{\circ}C$ for reaction time of 4 hr. As far as the dissolution of aluminum hydroxide with sulfuric acid was concerned, it was found that the optimum concentration of sulfuric acid was about 6 mole/l for the effective dissolution of aluminum hydroxide. When oxalic acid was used for the dissolution of aluminum hydroxide, nearly complete dissolution could be obtained by the dissolution for 16 hr with 1.0 mole/l oxalic acid at $90^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.72-76
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• 2016

We investigated the application of functional materials by examining a variety of physiological activities of Geranium krameri extract obtained from the National Institute of Horticultural and Herbal Science. Geranium krameri extract had a low cytotoxicity against murine melanoma B16F10 cells. At concentrations with little or no cytotoxicity, Geranium krameri extract showed high DPPH radical scavenging activity ($IC_{50}$, $8.72{\mu}g/mL$) and anti-microbial activities against Bacillus subtilis, Escherichia coli, and Candida albicans. Additionally, Geranium krameri extract inhibited tyrosinase activity ($IC_{50}$, $456.86{\mu}g/mL$) and decreased melanin content ($IC_{50}$, $50.35{\mu}g/mL$). The treatment of B16F10 cells with Geranium krameri extract suppressed the protein expression of tyrosinase in a dose-dependent manner. These findings suggest that Geranium krameri extract inhibits melanin synthesis in murine melanoma B16F10 cells by suppressing intracellular tyrosinase expression, as well as directly inhibits tyrosinase activity simultaneously.