Evaluation of Anticancer and Antioxidant Activity of a Commercially Available CO2 Supercritical Extract of Old Man's Beard (Usnea barbata)

Ana Zugic; Ivica Jeremic; Aleksandra Isakovic; Ivana Arsic; Snezana Savic; Vanja Tadic

doi:10.1371/journal.pone.0146342

Evaluation of Anticancer and Antioxidant Activity of a Commercially Available CO2 Supercritical Extract of Old Man's Beard (Usnea barbata)

PLoS One. 2016 Jan 8;11(1):e0146342. doi: 10.1371/journal.pone.0146342. eCollection 2016.

Authors

Ana Zugic¹, Ivica Jeremic^{2

3}, Aleksandra Isakovic³, Ivana Arsic⁴, Snezana Savic⁵, Vanja Tadic¹

Affiliations

¹ Institute for Medicinal Plant Research "Dr. Josif Pancic", Belgrade, Serbia.
² Institute of Rheumatology, University of Belgrade, Belgrade, Serbia.
³ Institute of Biochemistry, School of Medicine, University of Belgrade, Belgrade, Serbia.
⁴ Department of Pharmacy, Faculty of Medicine, University of Nis, Nis, Serbia.
⁵ Department of Pharmaceutical Technology and Cosmetology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia.

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.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Antineoplastic Agents, Phytogenic / isolation & purification
Antineoplastic Agents, Phytogenic / pharmacology*
Antioxidants / isolation & purification
Antioxidants / pharmacology*
Apoptosis / drug effects
Autophagy / drug effects
Benzofurans / isolation & purification
Benzofurans / pharmacology*
Biphenyl Compounds / antagonists & inhibitors
Carbon Dioxide / chemistry*
Cell Cycle / drug effects
Cell Line, Tumor
Chromatography, Supercritical Fluid / instrumentation
Chromatography, Supercritical Fluid / methods*
Mice
Oxidation-Reduction
Picrates / antagonists & inhibitors
Rats
Usnea / chemistry*

Substances

Antineoplastic Agents, Phytogenic
Antioxidants
Benzofurans
Biphenyl Compounds
Picrates
usnic acid
Carbon Dioxide
1,1-diphenyl-2-picrylhydrazyl

Grants and funding

Serbian Ministry of education, science and technological development (http://www.mpn.gov.rs/) supported this study through the Research Projects: “Functional and physiologically active plant materials with added value for usage in pharmaceutical and food industries” (Project No. III 45017) and “Modulation of intracellular energy balance controlling signaling pathways in therapy of cancer and neuro-immuno-endocrine disorders (Project No. III 41025). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.