Quantitation of Usnic acid from three Usnea species, its commercial formulations Using High-Performance Thin-Layer Chromatography-Mass Spectrometry (HPTLC-MS) and their metabolite profiling using UPLC-QTof-MSE.

Background: The genus Usnea (Parmeliaceae; lichenized Ascomycetes) is pale grayish-green fruticose lichens which grow as leafless mini-shrubs and comprise about 360 species. Most of the Usnea species are edible and is utilized in preparation of traditional foods as well as in medicines to combat wide range of ailments.

Objective: The goal of this work was to quantify usnic acid in three Usnea spp.