Phytochemical review of the lichen genus Stereocaulon (Fam. Stereocaulaceae) and related pharmacological activities highlighted by a focus on nine species

The Stereocaulon genus is one of the fruticose lichen groups distributed worldwide from tropical zones to polar zones. However, the scientific study of this tricky genus is still limited, making it a challenge to study the group further. Detailed morphological studies are essential to discriminate closely shaped species which is illustrated through personal data focused on phyllocladia, apothecia and spores of nine species. Secondary metabolites isolated from Stereocaulon species are mostly some depsides, depsidones, diphenylethers and dibenzofurans which can have a taxonomic value. The use of Stereocaulon lichens as a traditional medicine in several regions of the world and pharmacological studies of extracts and isolated compounds have been compiled. Biological activities as cytotoxic, anti-inflammatory, antibacterial, antifungal or antioxidant are reported.