Search results for "Terpene"
showing 10 items of 816 documents
Chemical Composition and Antibacterial Potential of Artemisia arborescens L. Essential Oil
2011
This study was undertaken to characterize the essential oil (EO) of Artemisia arborescens growing wild in Sicily. EO, extracted by steam distillation, was examined for its chemical composition and for its capability to inhibit some food-borne pathogen bacteria. A total of 43 compounds (13 monoterpene hydrocarbons, 14 oxygenated monoterpenes, 10 sesquiterpene hydrocarbons, three oxygenated sesquiterpenes and less amount of other three compounds), which account 93.73% of the total oil, were identified by gas chromatography and gas chromatography-mass spectrometry. Oxygenated monoterpenes (57.32%) constituted the main fraction, with β-thujone as the main compound (45.04%), followed by the sesq…
Combination strategies for enhancing transdermal absorption of sumatriptan through skin
2006
The aim of the present work was to characterize in vitro sumatriptan transdermal absorption through human skin and to investigate the effect of chemical enhancers and iontophoresis applied both individually and in combination. A secondary objective was to compare the results obtained with those in porcine skin under the same conditions, in order to characterize the relationship between the two skin models and validate the porcine model for further research use. Transdermal flux of sumatriptan was determined in different situations: (a) after pre-treatment of human skin with ethanol, Azone (1-dodecyl-azacycloheptan-2-one), polyethylene glycol 600 and R-(+)-limonene, (b) under iontophoresis a…
Cytotoxicity of Artesunic Acid Homo- and Heterodimer Molecules toward Sensitive and Multidrug-Resistant CCRF-CEM Leukemia Cells
2010
A novel approach to circumvent multidrug resistance is hybridization of natural products in dimers. We analyzed homodimers of two artesunic acid molecules and heterohybrids of artesunic acid and betulin in human CCRF-CEM and multidrug-resistant P-glycoprotein-overexpressing CEM/ADR5000 leukemia cells. Multidrug-resistant cells were not cross-resistant to the novel compounds. Collateral sensitivity was observed for artesunic acid homodimer. Artesunic acid and artesunic acid homodimer induced G0/G1 cell cycle arrest, apoptosis, and formation of reactive oxygen species.
Triterpene Saponins from Cyclamen trocopteranthum
2010
Two new triterpene saponins ( 1- 2) together with three known saponins, deglucocyclamin I ( 3), cyclamin ( 4), and mirabilin ( 5), were isolated from the tubers of Cyclamen trocopteranthum. They were elucidated as 3 beta- O-{4- O-[3-hydroxyl-3-methylglutaryl]- beta-D-xylopyranosyl-(1 --> 2)- beta-D-glucopyranosyl-(1 --> 4)-[ beta-D-glucopyranosyl-(1 --> 2)]- alpha-L-arabinopyranosyl}-16 alpha-hydroxy-13 beta,28-epoxy-oleanan-30-al ( 1) and 3 beta- O-{4- O-[3-hydroxyl-3-methylglutaryl]- beta-D-xylopyranosyl-(1 --> 2)-[ beta-D-glucopyranosyl-(1 --> 6)]- beta-D-glucopyranosyl-(1 --> 4)-[ beta-D-glucopyranosyl-(1 --> 2)]- alpha-L-arabinopyranosyl}-16 alpha-hydroxy-20,30-lactone-olean-12-ene ( 2…
Concentriols B, C and D, three squalene-type triterpenoids from the ascomycete Daldinia concentrica
2002
Abstract Three squalene-type triterpenoids named concentricols B, C and D ( 1 – 3 ) were isolated from the ethyl acetate extract of fruiting bodies of the xylariaceous ascomycete Daldinia concentrica . Their absolute structures were elucidated by analysis of 2D NMR, MS, IR and UV spectra, and the modified Mosher's method.
Effect of temperature on the release of carvacrol and cinnamaldehyde incorporated into polymeric systems to control growth and biofilms ofEscherichia…
2015
This study assessed the effect of temperature on the release of essential oil components incorporated by melt compounding into polymeric films. Specifically, polyethylene-co-vinylacetate (EVA) films containing carvacrol (CAR) and cinnamaldehyde (ALD), alone and in combination, were prepared and their surface and mechanical properties and antibacterial and anti-biofilm activity against Escherichia coli and Staphylococcus aureus were evaluated. The addition of ALD and CAR did not provoke variation in the surface morphology of EVA and allowed their delivery. At 37°C, films containing CAR, ALD or their combination (25+75%) were found to have the strongest bactericidal effect, whereas at lower t…
Sarcophytolide: a new neuroprotective compound from the soft coral Sarcophyton glaucum
1998
Abstract Bioactivity-guided fractionation of an alcohol extract of the soft coral Sarcophyton glaucum collected from the intertidal areas and the fringing coral reefs near Hurghada, Red Sea, Egypt resulted in the isolation of a new lactone cembrane diterpene, sarcophytolide. The structure of this compound was deduced from its spectroscopic data and by comparison of the spectral data with those of known closely related cembrane-type compounds. In antimicrobial assays, the isolated compound exhibited a good activity towards Staphylococcus aureus, Pseudomonas aeruginosa , and Saccharomyces cerevisiae. Sarcophytolide was found to display a strong cytoprotective effect against glutamate-induced …
Structure and stereochemistry of stenophyllolide, a germacrolide from Centaurea aspera var. Stenophylla
1984
Abstract A crystalline compound, named stenophyllolide, obtained from an extract of Centaurea aspera var. stenophylla was shown to be 9β,15-dihydroxygermacra-1(10),4,11-trien-6α,12-olide by X-ray analysis. The molecular structure of stenophyllolide was solved with orthorhombic space group P2 1 2 1 2 1 , a = 11.719 (5), b = 13.389 (5), c = 8.646 (5) A for Z = 4, by direct methods and refined to a final R of 0.06 for 1198 observed reflections.
Novel Acylated Triterpene Glycosides from Muraltia heisteria
2002
Four new acylated triterpene glycosides (1-4) have been isolated as two inseparable mixtures of the trans- and cis-3,4,5-trimethoxycinnamoyl derivatives (1,2 and 3,4) from the roots of Muraltia heisteria. The structures of these compounds were elucidated by various 1D and 2D NMR techniques, including (1)H and (13)C, COSY, NOESY, HSQC, TOCSY, and HMBC experiments and FABMS. Compounds 3 and 4 were shown to be cytotoxic in a human colon cancer cell line but did not show any ability to potentiate in vitro cisplatin cytotoxicity.
Acylated Preatroxigenin Glycosides from Atroxima congolana
2003
Six new acylated bisdesmosidic preatroxigenin saponins named atroximasaponins E1, E2 (1, 2), F1, F2 (3, 4), and G1, G2 (5, 6) were isolated as three inseparable mixtures of the trans- and cis-p-methoxycinnamoyl derivatives, from the roots of Atroxima congolana. Their structures were established through extensive NMR spectroscopic analysis as 3-O-beta-D-glucopyranosylpreatroxigenin-28-O-beta-D-xylopyranosyl-(1--4)-alpha-L-rhamnopyranosyl-(1--2)-[beta-D-glucopyranosyl-(1--3)]-[4-O-trans-p-methoxycinnamoyl]-beta-D-fucopyranoside (atroximasaponin E1, 1), and its cis-isomer, atroximasaponin E2 (2), 3-O-beta-D-glucopyranosylpreatroxigenin-28-O-beta-D-xylopyranosyl-(1--4)-alpha-L-rhamnopyranosyl-(…