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 a-pinene, camphene, β-pinene, thujol, camphor, β-chamigrene, and cadina-3,9-diene. There are also the compounds that can be considered as chemotaxonomic markers, namely β-myrcene for Salvia lavadulifolia, β-phelandrene for Salvia verticillata, τ-terpinene for Salvia stepposa, and isocaryophyllene and caryophyllene for Salvia officinalis. Certain compounds (such as ο-cymene present in Salvia canariensis and Salvia stepposa; β-trans-ocymene present in Salvia lavadulifolia, Salvia sclarea, and Salvia amplexicaulis; thujenone present in Salvia staminea, Salvia atropatana, Salvia jurisicii, and Salvia officinalis; and thujone present in Salvia azurea, Salvia lavandulifolia, Salvia hians, and Salvia triloba) can constitute chemotaxonomic advice for the aforementioned species. Also, the lack of certain compounds otherwise common in the individual sage species can be considered as chemotaxonomic advice (e.g., Salvia sclarea has no α-pinene and β-pinene; Salvia lavadulifolia lacks camphene; Salvia triloba lacks β-pinene and camphene; and Salvia officinalis lacks β-chamigrene, thujol, and cadina-3,9-diene).

Polar-bonded stationary phases (CN-silica and Diol-silica) are used with nonaqueous eluents in adsorption mode or with aqueous eluents in partition mode. This enables the application of these systems in two-dimensional separations because of the different selectivity and application to the separation of closely related compounds of similar physicochemical properties and retention behaviour. Similarly, multiphase plates, connected with C18 strips and silica layers, are used with aqueous and nonaqueous eluents. Such layers were applied for the separation of selected coumarins. Thus, differences in separation selectivity are applied for the separation of coumarin fractions from plant extracts of the Apiaceae family by two-dimensional thin-layer chromatography.