title: Evaluation of Anticancer and Antioxidant Activity of a Commercially Available CO2 Supercritical Extract of Old Man's Beard (Usnea barbata).
abstract: There is a worldwide ongoing investigation for novel natural constituents with cytotoxic and antioxidant properties. The aim of this study was to investigate chemical profile and stated biological activities of the supercritical CO2 extract (SCE) of old man's beard compared to the extracts obtained using the conventional techniques (Soxhlet extracts and macerate). The most abundant compound identified was usnic acid, which content was inversely proportional to the polarity of the solvent used and was the highest in the SCE, which was the sample revealing the highest cytotoxic activity in tested tumor cell lines (B16 mouse melanoma and C6 rat glioma), with lower IC50 values compared to pure usnic acid. Further investigations suggested both SCE and usnic acid to induce apoptosis and/or autophagy in B16 and C6, indicating higher cytotoxicity of SCE to be related to the higher degree of ROS production. A good correlation of usnic acid content in the extracts and their antioxidant capacity was established, extricating SCE as the most active one. Presented results support further investigations of SCE of old man's beard as a prospective therapeutic agent with potential relevance in the treatment of cancer and/or in oxidative stress-mediated conditions.
authors.affiliation: Institute for Medicinal Plant Research "Dr. Josif Pancic", Belgrade, Serbia.
authors.forename: Ana
authors.initials: A
authors.lastname: Zugic
authors.affiliation: Institute of Rheumatology, University of Belgrade, Belgrade, Serbia.|Institute of Biochemistry, School of Medicine, University of Belgrade, Belgrade, Serbia.
authors.forename: Ivica
authors.initials: I
authors.lastname: Jeremic
authors.affiliation: Institute of Biochemistry, School of Medicine, University of Belgrade, Belgrade, Serbia.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Isakovic
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Nis, Nis, Serbia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Arsic
authors.affiliation: Department of Pharmaceutical Technology and Cosmetology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia.
authors.forename: Snezana
authors.initials: S
authors.lastname: Savic
authors.affiliation: Institute for Medicinal Plant Research "Dr. Josif Pancic", Belgrade, Serbia.
authors.forename: Vanja
authors.initials: V
authors.lastname: Tadic
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001343:Autophagy / Q000187:drug effects; D001572:Benzofurans / Q000302:isolation & purification / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors; D002245:Carbon Dioxide / Q000737:chemistry*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D025924:Chromatography, Supercritical Fluid / Q000295:instrumentation / Q000379:methods*; D051379:Mice; D010084:Oxidation-Reduction; D010851:Picrates / Q000037:antagonists & inhibitors; D051381:Rats; D020949:Usnea / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D001572:Benzofurans; D001713:Biphenyl Compounds; D010851:Picrates; C073339:usnic acid; D002245:Carbon Dioxide; C004931:1,1-diphenyl-2-picrylhydrazyl