• Archives of Pharmacal Research
• /
• v.29 no.8
• /
• pp.617-623
• /
• 2006

In our ongoing search for bioactive compounds originating from the endemic species in Korea, we found that the hexane and EtOAc fractions of the MeOH extract from the root of Dystaenia takeshimana (Nakai) Kitagawa (Umbelliferae) showed cyclooxygenase-2 (COX-2) and 5- lipoxygenase (5-LOX) dual inhibitory activity by assessing their effects on the production of prostaglandin $D_2\;(PGD_2)$ and leukotriene $C_4\;(LTC_4)$ in mouse bone marrow-derived mast cells. By activity-guided fractionation, five coumarins, viz. psoralen (2), xanthotoxin (3), scopoletin (4), umbelliferone (5), and (+)-marmesin (6), together with ${\beta}-sitosterol$ (1), were isolated from the hexane fraction, and two phenethyl alcohol derivatives, viz. 2-methoxy-2-(4'-hydroxyphenyl)ethanol (7) and 2-hydroxy-2-(4'-hydroxyphenyl)ethanol (8), three flavonoids, viz. apigenin (9), luteolin (10), and cynaroside (11), as well as daucosterol (12) were isolated from the EtOAc fraction using silica gel column chromatography. In addition, D-mannitol (13) was isolated from the BuOH fraction by recrystallization. Two of the coumarins, scopoletin (4) and (+)- marmesin (6), the two phenethyl alcohol derivatives (7, 8) and the three flavonoids (9-11) were isolated for the first time from this plant. Among the compounds isolated from this plant, the five coumarins as well as the three flavonoids showed COX-2/5-LOX dual inhibitory activity. These results suggest that the anti-inflammatory activity of D. takeshimana might in part occur via the inhibition of the generation of eicosanoids.

• Parasites, Hosts and Diseases
• /
• v.61 no.4
• /
• pp.449-454
• /
• 2023

Free-living amoebae (FLA) rarely cause human infections but can invoke fatal infections in the central nervous system (CNS). No consensus treatment has been established for FLA infections of the CNS, emphasizing the urgent need to discover or develop safe and effective drugs. Flavonoids, natural compounds from plants and plant-derived products, are known to have antiprotozoan activities against several pathogenic protozoa parasites. The anti-FLA activity of flavonoids has also been proposed, while their antiamoebic activity for FLA needs to be emperically determined. We herein evaluated the antiamoebic activities of 18 flavonoids against Naegleria fowleri and Acanthamoeba species which included A. castellanii and A. polyphaga. These flavonoids showed different profiles of antiamoebic activity against N. fowleri and Acanthamoeba species. Demethoxycurcumin, kaempferol, resveratrol, and silybin (A+B) showed in vitro antiamoebic activity against both N. fowleri and Acanthamoeba species. Apigenin, costunolide, (-)-epicatechin, (-)-epigallocatechin, rosmarinic acid, and (-)-trans-caryophyllene showed selective antiamoebic activity for Acanthamoeba species. Luteolin was more effective for N. fowleri. However, afzelin, berberine, (±)-catechin, chelerythrine, genistein, (+)-pinostrobin, and quercetin did not exhibit antiamoebic activity against the amoeba species. They neither showed selective antiamoebic activity with significant cytotoxicity to C6 glial cells. Our results provide a basis for the anti-FLA activity of flavonoids, which can be applied to develope alternative or supplemental therapeutic agents for FLA infections of the CNS.

• Korean Journal of Pharmacognosy
• /
• v.7 no.4
• /
• pp.247-250
• /
• 1976

Phytochemical survey has been made of the occurrence of alkaloids, saponins, terpenoids and flavonoids in 43 Saudi Arabian plants. The result is presented in Table I.

• Korean Journal of Pharmacognosy
• /
• v.25 no.3
• /
• pp.214-220
• /
• 1994

From the Viticis Fructus n-hydrocarbons, ${\beta}-sitosterol$ $3-O-{\beta}-_D-glucoside$ and hesperidin along with the known polyoxygenated flavonoids such as vitexicarpin, artemetin and luteolin, and vanillic acid were isolated and identified by means of spectroscopic methods. HPLC analysis of the flavonoid components from the MeOH extract was established. Phytochemical analyses of the domestic plant sample and the imported ones were conducted and the flavonoid compositions of the domestic samples were greatly different from those of the imported ones.

• BMB Reports
• /
• v.42 no.1
• /
• pp.41-46
• /
• 2009

Post-transcriptional regulation of mRNA stability by Hu proteins is an important mechanism for tumorigenesis. We focused on the molecular interactions between the HuC protein and AU-rich elements (AREs) to find chemical inhibitors of RNA-protein interactions using RNA electrophoretic mobility shift assay with non-radioactive probes. Screening of 52 natural compounds identified 14 candidate compounds that displayed potent inhibitory activity. Six (quercetin, myricetin, (-)-epigallocatechin gallate, ellagic acid, (-)-epicatechin gallate, and rhamnetin) were categorized as phytochemicals, and their $IC_{50}$ values were low ($0.2-1.8\;{\mu}M$).

• Korean Journal of Pharmacognosy
• /
• v.25 no.1
• /
• pp.24-27
• /
• 1994

Two flavonoids, diosmetin 7-0-glucoside and lonicerin, and an iridoid, vogeloside have been isolated from the aerial parts of Lonicera japonica(Caprifoliaceae). The structures of these isolates have been determined by chemical transformations and interpretation of the spectral data. This is the first report of the isolation of diosmetin 7-O-glucoside from this plant.

• Archives of Pharmacal Research
• /
• v.16 no.4
• /
• pp.283-288
• /
• 1993

Fourteen flavonoids were evaluated for their effects as potential bradykinin (BK) antagonists. The compounds were evaluatd in several in vitro and in vivo (oral administration) systems ; inhibition of BK induced contractions in isolated rat ileum and uterus, antagonistic effects of BK induced plasma extravasation, reduction of acetic acid induced withing nociception and protection from endotoxic shock. Skullcapflavone II (3), baicalein (5), 5-methoxyflavone (11), 6-methoxyflavone (12) and 2'-methoxyflavone (14) showed effects in all the tests although the order of potency were somewhat varied.

• Archives of Pharmacal Research
• /
• v.25 no.4
• /
• pp.441-445
• /
• 2002

Three naphthalene glycosides (1-3), four flavonoids (4-7), and two galloyl glycosides (8-9) were isolated from the stem-bark of Juglans mandshurica (Juglandaceae). Their structures were determined by chemical and spectral means, including to 2D-NMR (COSY, HMQC, and HMBC) experiments. Amongst the isolated compounds, taxifolin (4) showed the most potent HIV-induced cytopethic activity against MT-4 cells with complete inhibitory concentration ($IC_{100}$) value of $25{\;}{\mu\textrm{g}}/ml$ and maximum cytotoxic concentration ($CC_{100}$) value of above $100{\;}{\mu\textrm{g}}/ml$. However, naphthalene glycosides (1-3), flavonoids (5-7)), and galloyl tannins (8-9) were inactive against anti-HIV-1 activity.

• Natural Product Sciences
• /
• v.13 no.3
• /
• pp.190-194
• /
• 2007

Two new flavonoid compounds, 8,8'-bisbaicalein 1 and baicalein-7-O-caffeate 2 along with six known flavonoids, baicalein, chrysin, scutellarein, 6-hydroxyluteolin, 6-methoxyluteolin and baicalein-7-Oglucoside and ${\beta}-sitosterol$ have been isolated from the stem-bark of Oroxylum indicum (Bignoniaceae) and identified on the basis of spectroscopic and chemical studies. 6-Hydroxyluteolin and 6-methoxyluteolin are reported for the first time from this plant.

• Natural Product Sciences
• /
• v.3 no.1
• /
• pp.49-54
• /
• 1997

We studied the attachment-repelling activity of flavonoids, stilbenes, and their glycosides against the blue mussel Mytilus edulis galloprouincialis. Molecular mechanics calculations have shown that the most stable conformations of potent repellents 29 and 32 were the same. On the basis of these results, structure-activity relationships of these compounds are discussed.