COMPARISON OF TLC AND HPLC FINGERPRINTS OF PHENOLIC ACIDS AND FLAVONOIDS FRACTIONS DERIVED FROM SELECTED SAGE (SALVIA) SPECIES

This study is part of a larger project on the contents and composition of essential oils, phenolic acids, and flavonoids originating from over twenty species belonging to the Salvia genus. These herbs are recognized in the traditional European pharmacy and cuisine for their curative and aromatic properties, and yet they have not attracted sufficient attention from the side of phytochemists. Thus, it seemed inevitable to focus on the contents of the phenolics in the individual sage species, basically due to the recognized antioxidant properties of this class of compounds. In this paper, we compared the results of a spectrophotometric assessment of the overall contents of phenolic acids and flavonoids (selectively extracted from twenty three different Salvia species) with those of a more detailed analysis carried out with use of HPLC/DAD and the TLC-based video imaging. Six species with the highest contents of phenolic acids and five species with the highest contents of flavonoids, and additionally Salvia officinalis, were chosen for the chromatographic fingerprinting of the selectively extracted fractions of the free and bonded phenolic acids, and the flavonoid aglycons and glycosides. As Salvia officinalis is the only representative of the discussed genus recognized as a medicinal plant by Polish Pharmacopoeia, our goal was to compare its phenolic contents with those of the other phenolic-rich sage species. This part of our sage investigation project has methodological importance and shows how thin-layer chromatographic video imaging can be used in a phytochemical study in combination with other analytical techniques.