Isolation of flavonoid aglycones from propolis by a column chromatography method and their identification by GC-MS and TLC methods

Ten flavonoid compounds were isolated by means of preparative column chromatography from propolis collected in southern Poland. Their mass spectra were taken and compared with a spectrum library. As a result, nine of them were identified as: tectochrysin, pinocembrin, chrysin, galangin, genkwanin, apigenin, kaempferol, pilloin, 5-hydroxy-4',7-dimethoxyflavone, and pinostrobin chalcone. Pilloin and pinostrobin chalcone were isolated from propolis for the first time. The optimum system of solvents for separation on a silica gel column was chosen on the basis on R-F vs. mixed solvent composition dependence, obtained by means of thin-layer chromatography.