Fingerprinting of the volatile fraction from selected thyme species by means of headspace gas chromatography with mass spectrometric detection.

The Thymus genus has a firm position in Mediterranean folk medicine and culinary tradition, and yet certain confusion is observed in its botanical taxonomy. Therefore, chemical analysis of secondary metabolites and selection of reliable chemotaxonomic markers can prove helpful. In this study, the volatile fraction derived from 20 different thyme specimens was analyzed by means of headspace GC with MS detection.

Fingerprint of selected Salvia species by HS-GC-MS analysis of their volatile fraction.

Twenty species of Salvia, naturally grown or cultivated in Poland, are investigated by headspace gas chromatography-mass spectrometry analysis. The main components of the volatile fraction of Salvia species are identified as alpha-pinene, camphene, beta-pinene, thujol, camphor, beta-chamigrene, and cadina-3,9-diene. There are also the compounds that can be considered as chemotaxonomic markers, namely beta-myrcene for Salvia lavadulifolia, beta-phelandrene for Salvia verticillata, tau-terpinene for Salvia stepposa, and isocaryophyllene and caryophyllene for Salvia officinalis.

Lipid oxidation. Part. 1. Effect of free carboxyl group on the decomposition of lipid hydroperoxide.

Hydroperoxido butyl oleate was decomposed by heating in excess palmitic acid at 60-120 degrees C. The decomposition followed the kinetics of a first order reaction with formation of both monomeric and oligomeric secondary products. The proportions of oligomers slightly increased with increasing reaction temperature and decreased with increasing concentration of hydroperoxide.