Screening of antimicrobial potential of methanolic, acetone and quencher extracts from Cladonia rangiformis Hoffm. and Cladonia pocillum Ach.

This study compared the efficacy of two species of lichen located in Tunisia belonging to Cladonia rangiformis and Cladonia pocillum species. The antibacterial and antifungal potentials of methanol, acetone and quencher extracts of C. rangiformis and C. pocillum and the lysozyme activity of both methanol extracts were investigated. The results showed that the examined extracts had antimicrobial properties against gram-positive and gram-negative bacteria and anti-Candida properties and that they also limited the spore germination of Penicillium and Aspergillus. Further results showed that the largest diameter of the inhibition zone was obtained by the methanolic extract of C. pocillum with 31 mm and 27.5 mm against E. cloacae and E. coli, respectively. MIC values of bactericidal and fungicidal activities of both Cladonia extracts ranged from 0.25 mg/mL to 2 mg/mL. C. pocillum possess superior lysozyme activity against Staphylococcus aureus and Enterococcus faecalis. Furthermore, the methanol extract of both Cladonia showed a remarkable destructive effect on the morphology of fungal hyphae.