Phytochemical constituents, antioxidant and antistaphylococcal activities of Evernia prunastri (L.) Ach., Pseudevernia furfuracea (L.) Zopf. and Ramalina farinacea (L.) Ach. from Morocco

The purpose of this work was to assess chemical composition, antibacterial activity against Staphylococcus aureus isolates from catheter-associated infections and antioxidant activity of methanol extracts of three lichens collected from Morocco. The phytochemical analysis of the methanol extracts of these lichens was performed by HPLC-UV method, the predominant phenolic compounds were evernic acid, physodalic acid and usnic acid for Evernia prunastri, Pseudevernia furfuracea and Ramalina farinacea, respectively. Total phenolic compounds and total flavonoid content of all extracts were also determined. As a result, Pseudevernia furfuracea extract had the strongest effect and the highest phenolic compounds content. All extracts showed antibacterial activity against all tested strains (MIC values ranging from 0.078 to 0.625 mg/mL), the strongest inhibition was obtained with the extract of Evernia prunastri.