Composition, antimicrobial and antioxidant activity of the extracts of Eryngium palmatum PaniA‡ and Vis. (Apiaceae)

The chemical composition, antimicrobial and antioxidant activity of Eryngium palmatum, an endemic plant species from the Balkan Peninsula, were investigated. The flavonoids apigenin (9.5 +/- 0.3 mg g(-1)) and apigenin 7-O-glucoside (2.4 +/- 0.1 mg g(-1)) were determined in a methanol extract of aerial parts using HPLC analysis. The methanol extract of roots contained catechin (5.0 +/- 0.1 mg g(-1)), epicatechin (2.9 +/- 0.1 mg g(-1)), chlorogenic acid (1.6 +/- 0.0 mg g(-1)), gallic acid (0.9 +/- 0.0 mg g(-1)) and rosmarinic acid (0.9 +/- 0.2 mg g(-1)). GC-FID and GCMS analysis of a chloroform extract of aerial parts showed that the main volatile constituents were falcarinol, linoleic acid, hexadecanoic acid and methyl linoleate (comprising 32.6%; 24.4%; 19.9; 13.2% of the volatile fraction, respectively), while octanoic acid, tetradecanol and dodecanol dominated in the chloroform extract of the roots (34.9%; 25.8%; 22.2% of the volatile fraction, respectively). Investigation of antimicrobial activity by broth microdilution showed that the methanol and chloroform extracts of aerial parts and roots exerted a significant effect (MIC 3.5-15.6 mu g mL(-1)) against tested Gram-positive and Gram-negative bacteria. The methanol extracts of aerial parts or roots exerted moderate ferric reducing antioxidant power, DPPH radical scavenging activity and hydroxyl radical scavenging activity.