RESUMO
A fast and practicable gas-liquid chromatographic method for the quantitation of non-esterified fatty acids (C14:0-C18:2) from 100 microliter plasma is described. This technique includes extraction, purification using the solvents n-heptane and 0.5 M Na2CO3, and methylation by 0.1 M HCl-methanol. Extraction, quantification and optimal methylation conditions without transmethylation have been investigated. Reproducibility is good and results agree with values found in the literature.
Assuntos
Ácidos Graxos não Esterificados/análise , Cromatografia Gasosa , Humanos , Metilação , Microquímica/métodosRESUMO
(-)Tabersonine and (-)-11-methoxytabersonine were isolated from fruits of Melodinus reticulatus. Stems and leaves contain uvaol and eight alkaloids, five of which were previously described: (-)tabersonine, venalstonidine, kopsinine, venalstonine and its 3-oxoderivative. Three are new: 19-hydroxyvenalstonine, 19-hydroxyvenalstonidine and 3-oxovenalstonidine.