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Phytochemical investigation of the whole plant of Filago vulgaris Lam. (Asteraceae) resulted in the isolation and characterization of seven compounds, including a rare methoxylated flavonol (araneol), tetrahydrofurofuranolignans (pinoresinol and syringaresinol), p-hydroxybenzaldehyde, vanillin, vanillic acid and scopoletin. The structures of the compounds were determined by NMR and mass spectroscopy. All compounds were first obtained from this species and reported for the genus Filago. Our results demonstrate that highly methoxylated flavonols lacking substituents on ring B and lignans can be regarded as taxonomic markers for the tribe Inuleae. The lipophilic extract of F. vulgaris was found to have antiproliferative activity against HeLa cells (62.1±0.9% inhibition at 30 μ/ml), and araneol was highly effective against this tumour cell line (IC 50 8.36 μ M).

Chelidonium majus or greater celandine is spread throughout the world, and it is a very common and frequent component of modern phytotherapy. Although C. majus contains alkaloids with remarkable physiological effect, moreover, safety pharmacology properties of this plant are not widely clarified, medications prepared from this plant are often used internally. In our study the inhibitory effects of C. majus herb extracts and alkaloids on hERG potassium current as well as on cardiac action potential were investigated. Our data show that hydroalcoholic extracts of greater celandine and its alkaloids, especially berberine, chelidonine and sanguinarine have a significant hERG potassium channel blocking effect. These extracts and alkaloids also prolong the cardiac action potential in dog ventricular muscle. Therefore these compounds may consequently delay cardiac repolarization, which may result in the prolongation of the QT interval and increase the risk of potentially fatal ventricular arrhythmias., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The extract of Artemisia asiatica herb with antiproliferative activity against four human tumor cell lines (A2780, A431, HeLa, and MCF7) was analyzed by the MTT assay, and bioassay-directed fractionation was carried out in order to identify the compounds responsible for the cytotoxic activity. Guaianolide (1-4), seco-guianolide (5), germacranolide (6) and eudesmanolide sesquiterpenes (7), monoterpenes (8, 9), including the new compound artemisia alcohol glucoside (8), and flavonoids (10-16) were isolated as a result of a multistep chromatographic procedure (CC, CPC, PLC, and gel filtration). The compounds were identified by means of UV, MS, and NMR spectroscopy, including (1)H-and (13)C-NMR, (1)H-(1)H COSY, NOESY, HSQC, and HMBC experiments. The isolated compounds 1-16 were evaluated for their tumor cell growth-inhibitory activities on a panel of four adherent cancer cell lines, and different types of secondary metabolites were found to be responsible for the cytotoxic effects of the extract. Especially cirsilineol (13), 3β-chloro-4α,10α-dihydroxy-1α,2α-epoxy-5α,7αH-guai-11(13)-en-12,6α-olide (3), and iso-seco-tanapartholide 3-O-methyl ester (5) exerted marked cytotoxic effects against the investigated cell lines, while jaceosidin (12), 6-methoxytricin (15), artecanin (2), and 5,7,4',5'-tetrahydroxy-6,3'-dimethoxyflavone (14) were moderately active. All the sesquiterpenes and monoterpenes are reported here for the first time from this species, and in the case of artecanin (2), 3α-chloro-4β,10α-dihydroxy-1β,2β-epoxy-5α,7αH-guai-11(13)-en-12,6α-olide (4), ridentin (6), and ridentin B (7), previously unreported NMR spectroscopic data were determined., (Georg Thieme Verlag KG Stuttgart · New York.)

The antiproliferative effects of n-hexane, chloroform and aqueous methanol extracts prepared from the whole plant of Centaurea arenaria M.B. ex Willd. were investigated against cervix adenocarcinoma (HeLa), breast adenocarcinoma (MCF7) and skin epidermoid carcinoma (A431) cells, using the MTT assay. The chloroform extract displayed high tumour cell proliferation inhibitory activity (higher than 85% at 10 μg/mL concentration), and was therefore subjected to a bioassay-guided multistep separation procedure. Flavonoids (eupatilin, eupatorin, 3'-methyleupatorin, apigenin and isokaempferid), lignans (arctigenin, arctiin and matairesinol), the sesquiterpene cnicin, serotonin conjugates (moschamine and cis-moschamine), β-amyrin and β-sitosterin-β-D-glycopyranoside, identified by means of UV, MS and NMR spectroscopy, were obtained for the first time from this species. The isolated compounds were also evaluated for their tumour cell growth inhibitory activities on HeLa, MCF7 and A431 cells, and different types of secondary metabolites were found to be responsible for the antitumour effects of the extracts; in addition to moderately active compounds (isokaempferid and moschamine), especially apigenin, eupatorin, arctigenin, arctiin, matairesinol and cnicin exert marked antitumour effects against these cell lines., (Copyright © 2010 John Wiley & Sons, Ltd.)

The antiproliferative activities of aqueous and organic extracts prepared from 26 Hungarian species of the tribes Cynereae and Lactuceae (Asteraceae) were tested in vitro against HeLa (cervix epithelial adenocarcinoma), A431 (skin epidermoid carcinoma) and MCF7 (breast epithelial adenocarcinoma) cells by using the MTT assay. Of the tested 200 extracts of different plant parts obtained with n-hexane, chloroform, 50% methanol and water, 16 extracts displayed noteworthy cell growth inhibitory activity (>50% inhibition at a concentration of 10 microg/mL). The IC50 values of these extracts were determined, and their direct cytotoxic effects were measured. High differences between the antiproliferative and cytotoxic activities, demonstrating a real cell proliferation inhibitory activity rather than direct killing effects, were found for some Centaurea, Cirsium, Cichorium, Lactuca, Onopordum and Scorsonera extracts., (Copyright 2009 John Wiley & Sons, Ltd.)

The antiproliferative activities of n-hexane, chloroform, aqueous-methanol and aqueous extracts of the aerial parts of the Achillea millefolium aggregate on three human tumour cell lines were investigated by means of MTT assays. The chloroform-soluble extract exerted high tumour cell proliferation inhibitory activities on HeLa and MCF-7 cells, and a moderate effect on A431 cells; accordingly, it was subjected to detailed bioactivity-guided fractionation. As a result of the multistep chromatographic purifications (VLC, CPC, PLC, gel filtration), five flavonoids (apigenin, luteolin, centaureidin, casticin and artemetin) and five sesquiterpenoids (paulitin, isopaulitin, psilostachyin C, desacetylmatricarin and sintenin) were isolated and identified by spectroscopic methods. The antiproliferative assay demonstrated that centaureidin is the most effective constituent of the aerial parts of yarrow: high cell growth inhibitory activities were observed especially on HeLa (IC(50) 0.0819 microm) and MCF-7 (IC(50) 0.1250 microm) cells. Casticin and paulitin were also highly effective against all three tumour cell lines (IC(50) 1.286-4.76 microm), while apigenin, luteolin and isopaulitin proved to be moderately active (IC(50) 6.95-32.88 microm). Artemetin, psilostachyin C, desacetylmatricarin and sintenin did not display antiproliferative effects against these cell lines. This is the first report on the occurrence of seco-pseudoguaianolides (paulitin, isopaulitin and psilostachyin C) in the Achillea genus.

Aqueous and organic extracts of 25 selected species from four tribes of Hungarian Asteraceae were screened in vitro for antiproliferative activity against HeLa (cervix epithelial adenocarcinoma), A431 (skin epidermoid carcinoma) and MCF7 (breast epithelial adenocarcinoma) cells, using the MTT assay. Twenty five of the 228 tested extracts from different parts of the species of Astereae (6), Inuleae (3), Heliantheae (5) and Anthemideae (11) demonstrated a substantial antiproliferative effect (at least 50% inhibition of cell proliferation) at 10 microg/mL against one or more of the cell lines. Complete dose-response curves were generated and IC(50) values were calculated for these active extracts, and their direct cytotoxic effects were determined. In summary, 11 of the tested 25 plants were found to be active and 4 of them (Anthemis ruthenica, Erigeron canadensis, Erigeron annuus and Inula ensifolia) had not been studied previously for either active compounds or anticancer properties., (Copyright (c) 2007 John Wiley & Sons, Ltd.)

From the n-hexane fraction of the fruits of Vitex agnus-castus, two labdane-type diterpenes, vitetrifolin B and C, were isolated by means of multiple chromatographic separations, together with the previously identified rotundifuran, vitexilactone and the sesquiterpene spathulenol. From the EtOAc fraction, eupatorin was identified for the first time, besides the known casticin, penduletin, vitexin and orientin. The n-hexane, EtOAc and MeOH-H(2)O fractions of the MeOH extract of Agni-casti fructus were subjected to in vitro antioxidant assays. The EtOAc extract displayed a significant concentration-dependent effect when tested by 1,1-diphenyl-2-picrylhydrasyl (DPPH) free radical assay (IC(50) = 68 microg/mL) and against the autooxidation of a standard rat brain homogenate (IC(50) = 14 microg/mL). The MeOH-H(2)O fraction was less active with 3643 microg/mL (DPPH test) and IC(50) = 125 microg/mL (rat brain homogenate), while the n-hexane phase proved to be inactive. The main flavonoid constituents of the EtOAc extract, casticin, vitexin and orientin were assayed for antioxidant activity and found that only casticin possesses a marked lipid peroxidation inhibitory effect (IC(50) = 0.049 mm) compared with that of the positive control ascorbic acid (IC(50) = 0.703 mm).

Plants and plant extracts play a crucial role in the research into novel antineoplastic agents. Four sesquiterpene lactones, artecanin (1), 3β-chloro-4α,10α-dihydroxy-1α,2α-epoxy-5α,7αH-guaia-11(13)-en-12,6α-olide (2), iso-seco-tanapartholide 3-O-methyl ether (3) and 4β,15-dihydro-3-dehydrozaluzanin C (4), were isolated from two traditionally used Asteraceae species (Onopordum acanthium and Artemisia asiatica). When tested for antiproliferative action on HL-60 leukemia cells, these compounds exhibited reasonable IC50 values in the range 3.6–13.5 μM. Treatment with the tested compounds resulted in a cell cycle disturbance characterized by increases in the G1 and G2/M populations, while there was a decrease in the S phase. Additionally, 1–3 elicited increases in the hypodiploid (subG1) population. The compounds elicited concentration-dependent chromatin condensation and disruption of the membrane integrity, as revealed by Hoechst 33258–propidium staining. Treatment for 24 h resulted in significant increases in activity of caspases-3 and -9, indicating that the tested sesquiterpenes induced the mitochondrial pathway of apoptosis. The proapoptotic properties of the sesquiterpene lactones were additionally demonstrated withannexin V staining. Compounds 1 and 2 increased the Bax/Bcl-2 expression and decreased the expressions of CDK1 and cyclin B2, as determined at the mRNA level by means of RT-PCR. These experimental results indicate that sesquiterpene lactones may be regarded as potential starting structures for the development of novel anticancer agents. [ABSTRACT FROM AUTHOR]

Two new 2,2-dimethyl-chromene derivatives and the new pentaisovaleryl sucrose were isolated from the roots of Artemisia asiatica together with the known 1-(5-acetyl-2,4-dihydroxy-phenyl)-3-methyl-butan-1-one, 6-hydroxytremetone and ( E )-coniferyl aldehyde. The structures of the compounds were elucidated by extensive 1D ( 1 H, 13 C and JMOD) and 2D ( 1 H– 1 H COSY, HSQC, HMBC and NOESY) NMR studies and APCIMS and HRESIMS investigations. 6-Acetyl-3,7-dihydroxy-2,2-dimethyl-chromene and 6-acetyl-3-hydroxy-2,2-dimethyl-chromene are biogenetically related to 1-(5-acetyl-2,4-dihydroxy-phenyl)-3-methyl-butan-1-one and 6-hydroxytremetone as all having isoprenoid acetophenone origin. All the isolated compounds were described for the first time from this species; interestingly none of them are related to the metabolites identified from the extracts of the aerial part of the plant. [ABSTRACT FROM AUTHOR]

The MeOH extract of the aerial parts of Artemisia asiatica significantly inhibited the xanthine oxidase (XO) induced uric acid production. Flavonoids were isolated from the active extract and identified as eupatilin (1), hispidulin (2), jaceosidin (3), cirsilineol (4), 5,7,4',5'-tetrahydroxy-6,3'-dimethoxyflavone (5), 6- methoxytricin (6) and chrysosplenetin (7). With the exception of cirsilineol and chrysoplenetin, all these flavonoids exerted marked XO-inhibitory effects, with IC50 values in the range 1.33-6.13 µM. The degree of XO inhibition by 1-3, 5 and 6 suggests the importance of the free OH group on C-7. Evaluation of the isolated compounds 1-7 for their free radical scavenging activity in DPPH tests, revealed the substantial antioxidant activity of 5,7,4',5'-tetrahydroxy-6,3'-dimethoxy-flavone (5), which contains orthodihydroxy and 5-hydroxy groups. In summary, the flavonoid-containing MeOH extract of A. asiatica exhibits dual action, inhibiting XO (1-3, 5, 6) and resulting in a reduced generation of reactive oxygen species, and additionally scavenging free radicals (5). [ABSTRACT FROM AUTHOR]