ABSTRACT
208The aim of this study is to investigate antioxidant and antibacterial activity of the methanol and acetone extracts of the lichens Ramalina dumeticola, Usnea baileyi, Heterodermia leucomela, and Telochistes flavicans. Total phenolic contents of the lichens are evaluated by Folin–Ciocalteu method. Both acetone and methanol extracts of R. dumeticola showed the highest total phenolic content which are 179.3 mg and 142.9 mg GAE/g of extract, respectively. Antioxidant activity was evaluated by DPPH free radical scavenging assay. Among the lichens tested, methanol extract of R. dumeticola showed the largest free radical scavenging activity (84.43% inhibition at a concentration of 1 mg/mL). The antibacterial activity was estimated by disc-diffusion method and also the minimal inhibitory concentration (MIC) by the broth microdilution method tested on six bacterial strains. R. dumeticola and U. baileyi extracts are the most active toward B. subtilis, S. aureus, and S. epidermidis. The present study showed that some of lichen extracts demonstrated a strong antioxidant and antibacterial effect.
