Qualitative and quantitative analysis of pharmacological active triterpenes in birch bark

Triterpene derivatives in plants are compounds most frequently exhibiting biological activities [1]. Qualitative and quantitative analysis of triterpenes of the bark of birch, Betula pendula, Betulaceae, was performed in this study. Crude triterpene mixtures were obtained by depositing with water from methanolic extracts. For qualitative analysis of obtained samples thin-layer chromatography (TLC) and high-pressure liquid chromatography (HPLC) methods were used [2, 3]. Triterpene standards (betulinic acid, betulin, oleanolic acid and lupeol) and samples were applied to TLC plates using „ CAMAG Linomat 5“ device. The Systems used for developing in TLC (mobile phase benzene: ethyl acetate: formic acid, 36:12:5) and HPLC (column: Hypersil ODS 5µm, eluent acetonitril: water 70: 30) were proved to be optimal for separation of analyzed triterpenes with partially very similar chemical structure. Quantitative analysis of separated components was performed by „Camag TLC Scanner 3“ densitometer. Obtained rates (%) of tested triterpene standards in external bark, betulin (14%), betulinic acid (4.5%), lupeol (5%) in relation to the inner bark betulin (0.078%), betulinic acid (0.023%) and lupeol (0.4%) showed that the external bark contains much more triterpene compoundsand therefore should be considered as raw material for their isolation.

Obtained qualitative and quantitative analysis results are reproducible. Use of blood gelatine proved that all tested compounds induce haemolysis of red blood cells.

References: 1. Bruneton, J. (1999) Pharmacognosy, Phytochemistry medicinal plants, 2nd edition, Tech&Doc, Paris.

2. Nyredy, Sz. (2001) Planar Chromatography, A retreospective View for the Third Millenium, Springer Scientific Publisher, Budakalász, Hungary.

3. Kovac-Besovic, E. et al. (2003) Bosnian Journal of Basic Sciences III 3: 9–26.