In this study, on the basis of the information supplied by NMR and HPLC-PDA data, we reported a quali-quantitative GC-MS study of 19 yellow Cuban propolis (YCP) samples collected in different regions of Cuba. The profiles of YCP samples allowed us to define two main types of YCP directly related to their secondary metabolite classes: type A, rich in triterpenic alcohols and with the presence of polymethoxylated flavonoids as minor constituents, and type B, containing acetyl triterpenes as the main constituents. For the first time, triterpenoids belonging to oleanane, lupane, ursane, and lanostane skeletons were reported as major compounds in propolis. Also, the presence of polymethoxylated flavones or flavanones was found for the first time in propolis.

In the present study, the phenolic composition analysis of seven red varieties of propolis, collected in different regions of Cuba, was evaluated by gas chromatography/mass spectrometry (GC-MS). Seventeen compounds were identified in all samples by the interpretation of their mass spectra. This appears to be the first report on the GC-MS analysis of isoflavonoids in the propolis. The results confirmed the presence of the main isoflavonoids isolated previously and suggested the general structure for the other five isoflavonoids. Vestitol, 7-O-methylvestitol, and medicarpin were present in high amounts in all propolis samples analyzed. This result indicates that propolis samples rich in isoflavonoids are not exclusively found in Pinar del Rio province and proves that GC-MS technique is a useful and alternative tool for the chemical analysis of tropical red propolis.

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Recebido em 18/2/08; aceito em 20/10/08; publicado na web em 25/3/09This work describes a validation of an analytical procedure for the analysis of petroleum hydrocarbons in marine sediment samples. The proposed protocol is able to measure n-alkanes and polycyclic aromatic hydrocarbons (PAH) in samples at concentrations as low as 30 ng/g, with a precision better than 15% for most of analytes. The extraction efficiency of fortified sediments varied from 65.1 to 105.6% and 59.7 to 97.8%, for n-alkanes and PAH in the ranges: C 16 -C 32 and fluoranthene -benzo(a)pyrene, respectively. The analytical protocol was applied to determine petroleum hydrocarbons in sediments collected from a marine coastal zone.

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Clusia minor L. is traditionally used to treat many disorders that including pain and inflammation such as sores and warts. Four extracts from the leaves of plant were prepared: hexane (CMH-A), ethyl acetate (CMH-B), methanol (CMH-C) and ethanol (CMH-E) and the pharmacological (antioxidant and anti-inflammatory properties) and toxicity effects were examined. Previously, the main constituents from CMH-A extract was revealed. Here, we present the GC/MS analysis of CMH-B and CMH-C. Thirty three compounds were identified in the CMH-B extract and twenty seven compounds in the CMH-C. The presence of D-α-tocopherol and lupeol was relevant in both extracts. The only sterols identified were sitosterol and stigmasterol. All of them showed effective radical scavenger properties in the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay, being CMH-E extract the most promissory (IC50 = 10.25 µg/mL). CMH-A, C and E extracts, administered topically (0.5–4 mg per ear), significant reduced ear edema induced by croton oil at 4 mg per ear, meanwhile CMH-B that was be able to significant reduce the inflammation at the dose of 2 mg per ear. We evaluated also the cytotoxic activity of the extracts against kidney cells (BHK), colon cancer (CT26), endothelial cancer cells (EA.hy926) and breast cancer (4T1). CMH-B extract showed the most cytotoxicity effect, with IC50 values in the range of 32.01-203.5 µg/mL. In addition, no oral acute toxicity after mice exposure to Clusia minor L. extracts was observed. The results suggest Clusia minor L. may be a good potential source of new bioactive agents for developing medicinal agents.

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Ephedrines are sympathomimetic amines which have central nervous system stimulating properties and, for this reason, some of them are forbidden in sport by the World Antidoping Agency (WADA). They are screened and quantitated in urine by several published techniques and confirmed by gas chromatography/mass spectrometry (GC/MS). In this paper, a simple and easy confirmation procedure for norpseudoephedrine, norephedrine, ephedrine and pseudoephedrine in human urine by GC/electron ionization (EI)-MS is described. After the addition of diphenylamine as internal standard, a liquid-liquid extraction procedure under alkaline conditions with tert-butyl methyl ether was applied to the samples. The analytes were derivatized with acetone and pyridine to form the correspondent oxazolidine derivatives (acetonide). The EI mass spectra of all the studied substances have many diagnostic ions with relative abundance in accordance with WADA requirements and show great structural information content. The fragmentation of theses derivatives is discussed.