ANALYSIS OF TUNISIAN TINCTORIAL LICHENS B Y CHROMATOGRAPHY

The research into a purple vegetable dye (Murex purple) suitable for a ccompanying an animal dye, or for replacing it led us to carry out a s tudy of 23 Tunisian lichen species. The analysis of 26 lichen substanc es, including 20 precursors and dyestuffs contained in these lichens, has been achieved using two chromatographic techniques: Thin Layer (TL C) and High Performance Liquid (HPLC). The TLC of lichen extracts and of two control substances, using three elution systems and six differe nt chemical and physical tests, proved to be a good technique for the qualitative analysis of lichens. The results obtained by HPLC confirm the analysis and determine the pigment and tinctorial precursor compos ition.