Evaluation of DNA Protective and Antimicrobial Properties of some Cladonia Species

The present study evaluated the DNA protective properties and antimicrobial activities of the methanol extracts of nine Cladonia species, namely C. pocillum, C. subulata, C. pyxidata, C. coniocraea, C. foliacea, C. firma, C. furcata, C. fimbriata and C. rangiformis collected in Turkey. DNA protection properties efficiency of Cladonia extracts was evaluated using pBR322 plasmid DNA. In vitro antimicrobial activities of methanol extracts against two Gram-negative bacteria (Escherichia coli and Proteus mirabilis), three Gram-positive bacteria (Staphylococcus aureus, Micrococcus luteus and Bacillus subtilis) and two fungal strains (Candida glabrata and Candida albicans) were examined using the disc diffusion method and through the determination of minimal inhibitory concentrations (MIC). DNA protective studies, all Cladonia extracts protected pBR322 plasmid DNA against damage caused by the hydrogen peroxide (H2O2) with ultraviolet (UV). The results demonstrated that the inhibition zones in the disc diffusion method ranged from 6.5 to 19.0 mm. MIC results were ranged from 3.12 to 6.25 mg/mL. Cladonia extracts show a better antimicrobial effect against bacterial strains than fungal strains. The highest antimicrobial effect among lichen species was demonstrated by Cladonia pocillum. Our results demonstrated that tested Cladonia extracts had strong antibacterial and DNA protective effects. This is the first comprehensive study to evaluate the DNA protective properties activity of Cladonia extracts.