CHEMICAL CONSTITUENTS OF THE LICHENS CETRARIA DELISEI, LOBARIA PULMONARIA, STEREOCAULON TOMENTOSUM AND USNEA HIRTA

Abstract

  A long series of aliphatic compounds extracted from the lichen tissues of Cetraria delisei, Lobaria pulmonaria, Stereocaulon tomentosum and Usnea hirta, and released by saponification of the residues, were deduced using GC, combined GC/MS and HrMS. Main components of the isolated fatty acids and alcohols showed chain length of C18 and C20 respectively. A mixture of C28 and C29 sterols was isolated from the lichens and characterised in the same way by GC and MS. Lichesterol was found as the main sterol compound in the extracts of Cetraria delisei and Usnea hirta. Of interest is the presence of squalene and homologues in the extracts and of two sesquiterpenes in Cetraria delisei.