Antioxidative and antimicrobial potentials of Parmelia saxatilis and Pseudoevernia furfuracea

Abstract

Even though numerous lichen species possess significant medical potentials they are still unexplored, and particularly species and strains originating from Serbia. Therefore, the aim of this study was to evaluate the antioxidative and antimicrobial potential of ethanol extracts of Parmelia saxatilis and Pseudoevernia furfuracea collected in Serbia. The tested extracts were good scavengers of DPPH radicals, with capacities ranging from 14.76% to 79.76% in P. saxatilis and from 21.39% to 90.04% in P. furfuracea. In P. saxatilis level of DPPH? neutralisation was highly correlated with phenol content (r2 = 0.9981) and in P. furfuracea with amount of total flavonoides (r2 = 0.9641). The extract of P. furfuracea inhibited the growth of all tested microorganisms with exception of Aspergillus flavus, while P. saxatilis extract affected only growth of bacterial species. Among tested microorganisms, Staphylococcus aureus and Klebsiella pneumoniae were the most sensitive, while Enterococcus faecalis, Pseudomonas aeruginosa as well as micromycetes were the least sensitive to tested extracts. Because of these potentials and the fact that their long term usage does not have any negative side effects on organism and development of microbial resistance, the extracts could be included in conventional therapy. [Projekat Ministarstva nauke Republike Srbije, br. 173032]