Essential fatty acid components and antioxidant activities of eight Cephalaria species from southwestern Anatolia

Abstract
The hexane extracts of eight Cephalaria (Dipsacaceae) species, which were collected from southwestern Anatolia, were obtained by Soxhlet apparatus. The fatty acids were derived to methyl esters and determined by gas chromatography/flame ionization detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS) systems. The dominant fatty acid components and maximum percentages were detected as myristic [in C. joppica (17.48 %)], palmitic [in C. cilicica, C. elmaliensis, C. isaurica, C. scoparia (19.51 %), and C. gazipashaensis], linoleic [in C. joppica (33.02 %), C. elmaliensis, C. dipsacoides, and C. gazipashaensis], α-linolenic (ALA) [in C. cilicica, C. elmaliensis, C. isaurica, C. scoparia, C. lycica, and C. gazipashaensis (47.95 %)] and oleic [in C. isaurica and C. dipsacoides (40.66 %)] acids. The antioxidant activity of all hexane extracts was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric thiocyanate (FTC), and thiobarbituric acid (TBA) methods. The results indicate that hexane extracts of Cephalaria species possess considerable antioxidant activity. The highest radical scavenging activity was detected in C. isaurica (IC50 = 741 μg/mL). The most effective species on lipid peroxidation are C. lycica and C. gazipashaensis in FTC and TBA assays, respectively. This study reveals that Cephalaria species are attractive sources of fatty acid components, especially the essential ones, as well as of effective natural antioxidants.