Antioxidant, antimicrobial and anticancer activities of three Parmelia species.
BACKGROUND
Lichens are symbiotic organisms consisting of algae and fungi. They are used for human and animal nutrition and in the production of colours, perfumes and alcohol. Lichens have also been used in traditional medicine to treat diseases such as jaundice, pulmonary, stomach and cranial diseases. In this study the acetone extracts of three lichens, Parmelia caperata, Parmelia sulcata and Parmelia saxatilis, were tested for their antioxidant, antimicrobial and anticancer potential.


RESULTS
Of the lichens tested, P. saxatilis had the highest free radical-scavenging activity (55.3% inhibition). Moreover, all tested extracts showed effective reducing power and superoxide anion radical scavenging. Strong relationships between total phenolic and flavonoid contents and antioxidant effects of the tested extracts were observed. The extract of P. sulcata was most active in terms of antimicrobial ability, with minimum inhibitory concentration values ranging from 0.78 to 12.5 mg L⁻¹. All extracts were found to have strong anticancer activity, with IC₅₀ values ranging from 9.55 to 22.95 µg mL⁻¹.


CONCLUSIONS
The present study showed that the tested lichen extracts exhibited strong antioxidant, antimicrobial and anticancer effects. This suggests that lichens may be used as possible natural antioxidant, antimicrobial and anticancer agents.
Department of Biology, Faculty of Science, University of Kragujevac, Radoja Domanovića 12, Kragujevac, Serbia. marijanakosanic@yahoo.com
Marijana M
MM
Kosanić
Branislav R
BR
Ranković
Tatjana P
TP
Stanojković
D000890:Anti-Infective Agents / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D000975:Antioxidants / Q000494:pharmacology*; D001688:Biological Products / Q000494:pharmacology / Q000627:therapeutic use; D045744:Cell Line, Tumor; D005419:Flavonoids / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D008011:Lichens / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D009369:Neoplasms / Q000188:drug therapy*; D010636:Phenols / Q000494:pharmacology / Q000627:therapeutic use*; D013481:Superoxides / Q000378:metabolism
D000890:Anti-Infective Agents; D000970:Antineoplastic Agents; D000975:Antioxidants; D001688:Biological Products; D005419:Flavonoids; D010636:Phenols; D013481:Superoxides