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GC-MS analysis of essential oil of some commercial Fennel teas
No full textFennel teas were prepared by classical infusion or microwave decoction of unbroken and crushed fruits, three pre-packaged teabags and two instant teas. Their volatile constituents were obtained by extraction with n-hexane and analysed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC–MS), using two columns with stationary phases of different polarity. Of the constituents 85–95% were identified on the basis of their GC retention times and their mass spectra in relation to authentic compounds. No volatile constituents were detected in one sample of instant tea. Conventional teas from crushed fruits and teas prepared from the other instant tea showed the highest levels of volatile constituents. Anethole (30–90%) and/or anisaldehyde (0.7–51%) were the main constituents of all the samples. Methychavicol (0.8–4.1%), eugenol (1.5–11.3%) and fenchone (0.5–47%) were detected in most samples. Carvone (2.1–6.1%) was presenting only some teabags and camphor (2.3–2.6%) in others. The volatile constituents of only one instant tea included limonene (1.4%) and α-terpineol (0.4%)
Membrane inlet mass spectrometry in the study of the release kinetics of volatile active principles in tisanes of vegetable drugs
No full textMembrane inlet mass spectrometry was applied to monitor the release of volatile active principles when vegetable drug are extracted in hot water solution
Mass-spectrometric Methodologies In Plant Analysis - the Case of Flavonols In Sedum-telephium L Juice
No full textNegative-ion fast-atom bombardment mass spectrometry together with precursor and product-ion spectroscopies has been validly employed in the identification of six flavonol glycosides present in the juice of Sedum telephium leaves. The proposed technique proved to be a valuable alternative to the combination of high performance liquid chromatography and mass spectrometry in the analysis of the complex polyphenol mixtures present in some medicinal plants
Formation of inclusion complex between the non-steroidal anti-inflammatory drug (RS)-2-(4-isobutylphenyl)-propiohydroxamic acid and beta–cyclodextrin
No full text(RS)-2-(4-isobutylphenyl)-propiohydroxamic acid is a non-steroidal anti-inflammatory drug, which forms a equimolecular complex with beta–cyclodextrin, thus increasing the solubilization and the rate of dissolutono f the drug. The inclusion complex in aqueous solution and in solid phase, was studied by solubility methods, spectroscopy (UV, IR, 1H NMR), thermal analysis (DSC, TG). X-ray diffractometry and paper chromatography (PC). Rsults confirmed the formation of this comple
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