Thin Layer Chromatography and Chemometric Studies of Selected Potentilla Species

Abstract

Herbal medicinal products have a long-standing therapeutic record. To ensure the quality of herbal products specific identification tests which allow experts to discriminate related species and/or potential adulterants/substitutes are required. The purpose of the research was to recommend an original and simple method for the separation of closely related five triterpenic acids (ursolic, oleanolic, tormentic, euscaphic, pomolic acid) and its application to chemotaxonomy studies. 17 standard samples of Potentilla species and 3 test samples were chromatographed (with or without prechromatographic derivatization) on silica gel plates using the mobile phase: chloroform-diethyl ether-methanol-formic acid (30:10:1:0.2 v/v/v/v); they were subsequently derivatized, and visualized in UV 366 nm light. After images received pre-treatment (montaging stack, removal of noise, background subtract, horizontal equalization, two types of warping) exploratory analysis of the investigated Potentilla species fingerprints was processed. The method without prechromatographic derivatization was used to create differential fingerprints. Good results were obtained by the application of r-project iterative algorithm for subtract background and our simple algorithm for warping to image processing of TLC chromatograms for the first time.