HPTLC-guided flash chromatographic isolation and spectroscopic identification of bioactive compounds from olive flowers

The goal of preparative chromatography is to isolate suitable amounts of compound(s) at the required purity in the most cost-effective way. This study analyses the power of High-performance thin-layer chromatography (HPTLC) guided preparative flash chromatography to separate and isolate bioactive compounds from an olive flower extract for their further characterisation via spectroscopy. The structure and purity of isolated bioactive compounds were assessed using Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. Flash chromatography of the olive flower extract successfully isolated pure oleanolic and maslinic acids. Moreover, the flash chromatography of the extract allowed isolation and phytochemical analysis of the most lipophilic fraction of the extract, which was found to contain n-eicosane and n-(Z)-eicos-5-ene, that has not been isolated previously with preparative TLC.