Dibenzofurans from Lichens – A Pharmacological Overview

Lichens are a symbiotic association between a fungus (mycobiont) and a green algae/- cyanobacterium (photobiont). Lichens are a source of secondary metabolites, most of them being exclusively for these species, among which dibenzofurans are found. Dibenzofurans are a small group (over 35 different identified compounds), being usnic acid the most studied. In the last 10 years, there has been a growing interest in the pharmacological activity of dibenzofurans. In this work, dibenzofurans isolated from lichens (alectosarmentin, condidymic acid, didymic acid, isousnic acid, isostrepsilic acid, usimines A-C and usnic acid) were reviewed, most of which showed antibacterial, antifungal, and cytotoxic activities. These findings provide future guidance for research on pharmacological activity of dibenzofurans.