European Taxa of Saxicolous Lecidella Containing Chloroxanthones:Identification of Patterns Using Thin Layer Chromatography

Abstract

AbstractA method using TLC to recognize compound patterns consisting almost entirely of chloroxanthones in European saxicolous species of Lecidella is described. These are necessary for diagnosis of the taxa studied and of their chemotypes. Two solvents with complementary separatingqualities were required: C, toluene-glacial acetic acid (100:15); J, dichloromethane-acetone (4:1). Although the Rf values in solvent J strongly depend on the concentration of the substances, it is very suitable for identification because the xanthones in this system reveal distinct and characteristic fluorescence colours in UV light, simplifying interpretation enormously. No spray reagents are used. Identifications are made by co-chromatography with authentic lichencompounds