Showing papers on "Isopimpinellin published in 2003"

Cytotoxic Activity of Coumarins from the Fruits of Cnidium monnieri on Leukemia Cell Lines

Abstract: Cnidii monnieri Fructus [CmF; Cnidium monnieri (L.) Cusson] is used as a tonic agent in traditional Chinese medicine. In a previous Chinese herb-cytotoxicity screening test, the ethanol extract of CmF exhibited strong effects on human leukemia (HL-60), cervical carcinoma (HeLa) and colorectal carcinoma (CoLo 205) cells. Then, the CmF extract was subjected to silica gel column chromatography and recrystallization to give five coumarins: osthol, imperatorin, bergapten, isopimpinellin, and xanthotoxin. Among these compounds, osthol showed the strongest cytotoxic activity on tumor cell lines. The structure-activity relationship established from the results indicated that the prenyl group has an important role in the cytotoxic effects. However, imperatorin showed the highest sensitivity to HL-60 cells and the least cytotoxicity to normal PBMCs. Osthol and imperatorin both caused apoptotic bodies, DNA fragmentation, and enhanced PARP degradation in HL-60 cells by biochemical analysis. These results indicate that osthol and imperatorin can induce apoptosis in HL-60 cells. Therefore, osthol and imperatorin are cytotoxic marker substances in the fruits of Cnidium monnieri.

Cytotoxic and antiplatelet aggregation principles of Ruta graveolens

Abstract: Nineteen compounds have been isolated from the methanol extract of the root and aerial parts of Ruta graveolens. The structural elucidation of these isolated compounds were determined by the spectroscopic methods and/or comparison of the physical data with literature values. Their antiplatelet aggregation and cytotoxic activities were examined to find potent antiplatelet aggregation and cytotoxic compounds from natural resources. Among them, dictamine (5), skimmianine (7), psoralen (8), chalepensin (12), clausindin (13), and graveolinine (16) showed significant inhibition of platelet aggregation, induced by arachidonic acid and collagen. Arborinine (2), dictamine (5), isopimpinellin (11), clausindin (13), and graveoline (17) exhibited cytotoxic activity against KB, Hela, DLD, NCI and Hepa tumor cell lines.

Naturally occurring coumarins inhibit human cytochromes P450 and block benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene DNA adduct formation in MCF-7 cells.

Abstract: Naturally occurring coumarins (NOCs) inhibit polycyclic aromatic hydrocarbon-induced skin tumor initiation in mice by blocking cytochrome P450 (P450)-mediated bioactivation of benzo[a]pyrene (B[a]P) and 7,12-dimethylbenz[a]anthracene (DMBA). Bergamottin selectively inhibits tumor initiation by B[a]P, whereas imperatorin and isopimpinellin inhibit tumor initiation with both carcinogens. The goals of the current study were to examine the ability of NOCs to inhibit human P450s in vitro and to establish whether NOCs, which are anticarcinogenic in mice, can block carcinogen bioactivation in cultured human cells. For the initial experiments, incubations containing 5 microM P450, P450 substrate, an NADPH generating system, and NOCs were used to determine the concentrations of each inhibitor that blocked 50% of P450 activity (IC(50)). These results confirmed that NOCs are capable of inhibiting multiple human P450s and that they exhibit selectivity for certain isoforms of human P450s. In subsequent experiments, we examined the effects of bergamottin, imperatorin, and isopimpinellin on DMBA and B[a]P DNA adduct formation in the human breast MCF-7 adenocarcinoma cell line. Coincubation of cells with the three different NOCs significantly inhibited DMBA DNA adduct formation by 29-82% at doses ranging from 2 to 10 microM and significantly inhibited B[a]P DNA adduct formation by 37-80% at doses ranging from 20 to 80 microM. HPLC analysis of the DNA hydrolysates demonstrated that inhibition of DNA adducts corresponded to inhibition of the major B[a]P and DMBA diol-epoxide-derived adducts. Although bergamottin was not effective at blocking DMBA bioactivation in the mouse skin model, it was similar in effectiveness to imperatorin and isopimpinellin in MCF-7 cells. These results demonstrate that NOCs, which are present in citrus fruits and other components of the human diet, are capable of inhibiting carcinogen metabolizing enzymes and blocking bioactivation of both B[a]P and DMBA in MCF-7 cells.

Constituents of Peucedanum zenkeri seeds and their antimicrobial effects.

Abstract: The methanol extract of Peucedanum zenkeri L. seeds showed antimicrobial activity which is concentrated in the n-hexane fraction. Bioactivity-guided chromatographic fractionation of the seeds of P. zenkeri led to the isolation and characterization of five major coumarins, umbelliprenin, imperatorin, bergapten, isopimpinellin and byakangelicin, as well as two minor coumarins, 7-methoxy coumarin and 5-hydroxy-8-methoxy psoralen. Amongst the isolated compounds only imperatorin, bergapten and isopimpinellin were found to possess anti-microbial activity.

HPLC-NMR/HPLC-MS analysis of the bark extract of Stauranthus perforatus

Abstract: A combination of HPLC-MS and HPLC-NMR techniques has been used to analyse the cytotoxic fractions of the dichloromethane extract of bark of Stauranthus perforatus Six furanocoumarins (byakangelicol, heraclenin, heraclenol, imperatorin, isopimpinellin and xanthotoxin) and nine quinoline alkaloids (two known compounds, veprisine and 5-hydroxy-1-methyl-2-phenyl-4-quinolone, along with seven novel compounds, stauranthine, 3',4'-dihydroxy-3',4'-dihydroveprisine, 3',4'-dihydroxy-3',4'-dihydrostauranthine, 3',6'-dihydroxy-3',6'-dihydroveprisine, 3',6'-dihydroxy-3',6'-dihydrostauranthine, 6'-hydroxy-3'-ketoveprisine and 6'-hydroxy-3'-ketostauranthine) have been identified in the fractions

The furanocoumarins in the roots of Heracleum sibiricum L.

Abstract: From roots of Heracleum sibiricum L (cow parsnip) collected natural state, a raw crystalline furanocoumarin precipitate was obtained containing four compounds: bergapten, isopimpinellin, pimpinellin, sphondin. The isolated compounds were identified with H1NMR.

Studies on the coumarins in the root of Zanthoxylum dimorphophyllum

Abstract: Objective To study the chemical constituents of the dried roots of Zanthoxylum dimorphophyllumr. spinifolium and to find out the active constituents of the plant. Method Modern chromatography was used to purify chemical constituents, and their structures were identified by various spectral methods. Result Four compounds were isolated and identified as isopimpinellin (I), xanthoxyletin (II), 6-(2', 3'-dihydroxy-3'-methyl-butyl)-7-hydroxy-2H-1-benzopyran-2-one (III), 6-(2'-O-beta-D-glucopyranosyloxy, 3'-dihydroxy-3'-methybutyl)-7-hydroxy-2H-1-benzopyran-2-one (IV). Conclusion All of the above compounds were isolated from the above mentioned plant for the first time.