Bioactivity of Pseudevernia furfuracea Extracts: Antioxidant and Antibacterial Assessment

Lichens represent a promising source of novel molecules with diverse biological activities. This study aims to evaluate the antioxidant and antibacterial properties of extracts from the lichen Pseudevernia furfuracea to assess its potential for valorization in the pharmaceutical and food industries. Following a preliminary morphological characterization of the thallus, extraction was performed via maceration using three solvents: methanol, ethyl acetate, and dichloromethane. Antioxidant activity was quantified through three distinct methods (DPPH, CAT, and FRAP assays), while antibacterial efficacy was tested against four ATCC-referenced bacterial strains (Enterobacter cloacae ATCC 13047; Klebsiella pneumoniae ATCC 700603; Staphylococcus aureus ATCC 25923 and Staphylococcus aureus ATCC 43300 ) using the agar diffusion technique. The results demonstrated significant antioxidant activity of the ethyl acetate extract (IC50=71,72 µg/ml of DPPH assay and 66,66 mg EAA/g extract of cat assay), whereas the methanolic and dichloromethane extracts exhibited moderate activity. The results of the antibacterial activity assessment revealed that all tested strains exhibited susceptibility to the extracts. Notably, the ethyl acetate extract was found to be the most effective, demonstrating significantly greater efficacy than the other solvents used. The pronounced efficacy of the ethyl acetate extract is attributed to its richness in bioactive secondary metabolites, underscoring its potential for applications in medicinal and cosmetic formulations.