• Archives of Pharmacal Research
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• v.27 no.11
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• pp.1132-1135
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• 2004

In order to find new tyrosinase inhibitors and the effects of prenyl residue on flavonoid molecules, eight prenylated and three synthetic vinylated flavonoids were examined on their inhibitory effect against tyrosinase activity. From the results, kuwanon C, papyriflavonol A, sanggenon D and sophoflavescenol were found to possess the considerable inhibitory activity. Especially, sanggenon D is revealed as a potent inhibitor ($IC_{50}$ =7.3$\mu$ M), compared to the reference compound, kojic acid ($IC_{50}$ =24.8 $\mu$M). However, the prenylation with isoprenyl group or the vinylation to flavonoid molecules did not enhance tyrosinase inhibitory activity.

• Molecules and Cells
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• v.27 no.3
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• pp.345-350
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• 2009

We previously reported that flavone induces embryonic lethality in Caenorhabditis elegans, which appeared to be the result of cell cycle arrest during early embryogenesis. To test this possibility, here we examined whether flavone inhibits the activity of a key cell cycle regulator, CDC-25.1 in C. elegans. A gain-of-function cdc-25.1 mutant, rr31, which exhibits extra cell divisions in intestinal cells, was used to test the inhibitory effects of flavone on CDC-25 activity. Flavone inhibited the extra cell divisions of intestinal cells in rr31, and modifications of flavone reduced the inhibitory effects. The inhibitory effects of flavone on CDC-25.1 were partly, if not completely, due to transcriptional repression.

• Korean Journal of Pharmacognosy
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• v.33 no.2 s.129
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• pp.144-150
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• 2002

The methanol extracts of 132 herbal medicines were screened for the inhibitory activity against heparinase enzyme from Flavobacterium heparinum. Eleven medicinal plants, Amomum xanthiodides, Agrimonia pilosa, Paeonia lactiflora, Rubia cordifolia, Sanguisorba officinalis, Torrega grandis, Morus alba, Gleditsia sinensis, Crataegus pinnatifida, Cornus officinalis, Paeonia japonica showed potent inhibition on heparinase activity. The active substituents of those herbal medicine could be extracted into butanol fraction and the inhibitory compounds of Morus alba are now isolating.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2391-2396
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• 2011

Benzonaphthofurandiones containing four coplanar fused aromatic rings were synthesized and evaluated for their cytotoxicity against five human cancer cell lines, and their inhibitory activity on topoisomerases. These benzonaphthofurandiones were prepared by condensation of 2,3-dichloronaphthoquinone and three aromatic diols with base catalysts in alcohol. The synthesized compounds were o-alkylated with six dialkylaminoalkyl halides. The hydroxy derivatives (8a-8g) exhibited relatively potent cytotoxicity among the prepared compounds. These compounds were evaluated as excellent inhibitors against topoisomerase II (topo II). Especially, the hydroxy analogue with branched methyl side chain (8e) showed high cytotoxicity against cancer cell lines and good inhibitory activity on topo II.

• Plant Resources
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• v.4 no.3
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• pp.196-199
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• 2001

Medicinal plants were screened for the inhibitory effects on human immunodeficiency virus type 1 pretense. Of the extracts tested, the strong inhibitory effects were observed in the acetone extracts of the pericarp of Camellia japonica. Camelliatannin H from the pericarp of C. japonica showed a potent inhibitory activity on HIV-1 pretense. Effects of the extract and compound from leaves of Zanthoxylum piperitum on the enzyme activities were investigated in the liver of bromobenzene-treated rats. The methanol extract and protocatechuic acid isolated from Z. pipetitum reduced the activity of aniline hydroxylase that increased by bromobenzene, while did not affect the activities of aminopyrin N-demethylase and glutathione S-transferase. The extract and protocatechuic acid recovered significantly the activity of epoxide hydrolase decreased by bromobenzene.

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.269-272
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• 1994

The effect of the root of Coptis japonica (COPT), both dichloromethane soluble $(CH_2Cl_2)$ and insoluble $(H_2O)$ fractions, on catecholamine contents and tyrosine hydorxylase (TH) activity in PC12 cells was investigated. $(CH_2Cl_2){\;}and{\;}H_2O$ fractions showed 21 and 53% inhibitions on dopamine content, respectively, at a ocncentraction of 40 .mu.g/ml in medium : the $(H_2O)$ fraction proveided a grateer inhibitory effect. The TH activity was reduced by the treatment of COPT ($(H_2O)$ fraction). These results suggest that COPT has an inhibitory effect on the catecholamine biosynthesis by the reduction of TH activity in PC12 cells.

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1013-1018
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• 2005

A number of 1,5-diarylimidazoles has been synthesized and evaluated for their inhibitory activities of COX-2 catalyzed $PGE_2$ production. 1,5-Diarylimidazoles were obtained from imimes and p-toluenesulfonylmethyl cyanide (TosMIC). Imines were prepared from commercially available amines and aldehydes. Among the compounds tested, 1-(2,4-difluorophenyl)-5-(4­methylsulfonylphenyl)imidazole (2r) showed strong inhibitory activity, however, most diarylimidazoles exhibited little to low inhibitory activities against COX-2 catalyzed $PGE_2$ production.

• YAKHAK HOEJI
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• v.49 no.5
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• pp.365-369
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• 2005

The inhibitory effect of ferulic acid and related phenolic compounds on the growth of normal cell lines and can­cer cell line was evaluated by the MTT and XTT methods. Ferulic acid decreased the cell viability of human skin melanoma cells by the MTT method and the cell adhesion activity of human oral epithelioid carcinoma cells by the XTT method. These results suggest that ferulic acid has a potential anticancer activity.

• Korean Journal of Pharmacognosy
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• v.33 no.1 s.128
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• pp.69-73
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• 2002

The methanol extracts of 162 herbal medicines were screened for the inhibitory activity against VHR dualspecificity protein tyrosine phosphatase (DS-PTPase). Seventeen medicinal plants, Scutellaria baicalensis, Cuscuta chinensis, Caesalpinia sappan, Arecae pericarpium, Rubus coreanus, Machilus thunbergii, Amsonia elliptica Cinnamomum cassia, Arisaema erubescens, Pueraria thunbergiana, Dendrobium moniliforme, Mentha arvensis, Peucedanum japonicum, Salvia miltiorrhiza, Leonurus sibiricus, Siegesbeckia orientalis, Prunella vulgaris showed potent VHR DS-PTPase inhibitory activity.

• Korean Journal of Pharmacognosy
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• v.31 no.3
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• pp.320-324
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• 2000

Methanol extracts of 94 Korean plants were screened for angiogenesis inhibitors using the tube-like formation assay of HUVEC (Human Umbilical Vein Endothelial Cell) and evaluated for growth inhibitory activity on A549 cells, human lung cancer cells. Extracts of Euphorbia sieboldiana, Adonis amurensis, and Anthriscus sylvestris showed antiangiogenic and growth inhibitory activity at $50\;{mu}g/ml$. Aristolochia manshuriens and Styrax obassia expressed antiangiogenic activity without growth inhibitory action.