title: Chemical composition of three Parmelia lichens and antioxidant, antimicrobial and cytotoxic activities of some their major metabolites.
abstract: The aim of this study is to investigate chemical composition of acetone extracts of the lichens Parmelia caperata, P. saxatilis and P. sulcata and antioxidant, antimicrobial and anticancer activities of some their major metabolites. The phytochemical analysis of acetone extracts of three Parmelia lichens were determined by HPLC-UV method. The predominant phenolic compounds in these extracts were protocetraric and usnic acids (P. caperata) and depsidone salazinic acid (other two species). Besides these compounds, atranorin and chloroatranorin, were also detected in some of these extracts. Antioxidant activity of their isolated metabolites was evaluated by free radical scavenging, superoxide anion radical scavenging and reducing power. As a result of the study salazinic acid had stronger antioxidant activity than protocetraric acid. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method. Both compounds were highly active with minimum inhibitory concentration values ranging from 0.015 to 1mg/ml. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using MTT method. Salazinic acid and protocetraric acid were found to be strong anticancer activity toward both cell lines with IC(50) values ranging from 35.67 to 60.18μg/ml. The present study shows that tested lichen compounds demonstrated a strong antioxidant, antimicrobial, and anticancer effects. That suggest that these lichens can be used as new sources of the natural antimicrobial agents, antioxidants and anticancer compounds.
authors.affiliation: Department of Pharmacy, Medical Faculty, University of Kragujevac, Kragujevac, Serbia.
authors.forename: Nedeljko
authors.initials: N
authors.lastname: Manojlović
authors.forename: Branislav
authors.initials: B
authors.lastname: Ranković
authors.forename: Marijana
authors.initials: M
authors.lastname: Kosanić
authors.forename: Perica
authors.initials: P
authors.lastname: Vasiljević
authors.forename: Tatjana
authors.initials: T
authors.lastname: Stanojković
mesh_terms: D000890:Anti-Infective Agents / Q000302:isolation & purification*; D000970:Antineoplastic Agents / Q000302:isolation & purification*; D000975:Antioxidants / Q000302:isolation & purification*; D001572:Benzofurans / Q000302:isolation & purification; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D006575:Heterocyclic Compounds, 3-Ring / Q000302:isolation & purification; D006801:Humans; D007783:Lactones / Q000302:isolation & purification; D008011:Lichens / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D012459:Salicylates / Q000302:isolation & purification
chemical_list: D000890:Anti-Infective Agents; D000970:Antineoplastic Agents; D000975:Antioxidants; D001572:Benzofurans; D006575:Heterocyclic Compounds, 3-Ring; D007783:Lactones; D012459:Salicylates; C578352:protocetraric acid; C116675:salazinic acid; C073339:usnic acid