Use of HPTLC, HPLC, and Densitometry for Qualitative Separation of Indole Alkaloids from Rauvolfia serpentina Roots

High-performance thin-layer chromatography (HPTLC) has been used for normal-phase separation of the components of hexane, chloroform, methanol, and water extracts of Rauvolfia serpentina roots. Computerized densitometry was used for two-dimensional spectrographic image analysis of the HPTLC plates. High performance liquid chromatography (HPLC) was also used for reversed-phase separation of these extracts. Different chromatograms of R. serpentina root extracts, obtained by use of these techniques, revealed the presence of three marker indole alkaloids, ajmaline, ajmalicine, and reserpine, in all four extracts. Use of chloroform resulted in most efficient extraction of these three alkaloids. The results also showed that defatting with hexane may result in loss of the alkaloids.