Hydrocarbons and Fatty Acids from Echinops integrifolius

Abstract

The composition of volatile compounds from various fractions of the EtOH extract of Echinops integrifolius Kar. et Kir. [1] and the isolation from the plant of four triterpenes, six flavonoids, and one coumarin [2] were reported in previous studies.Herein we communicate results from an investigation of neutral components from the aerial part and roots of this plant.Neutral components were extracted (4u) from the air-dried aerial part using petroleum ether; from the roots, Et 2 O in a Soxhlet apparatus. The extract of the aerial part was worked up by the literature method [3] in order to prepare methyl esters of fatty acids (MEFA). The resulting heptane solution of MEFA was analyzed by GC-MS (Table 1). Gas chromatography was carried out on an Agilent 7890A-5975C GC-MS using an HP-Innowax column (30 m u 0.25 mm u 0.25 Pm), He carrier gas, flow rate 0.5 mL/min, injector temperature 230°C, and heating regime 2 min at <100°C, from 100 to 200°C at 4°C/min, 200°C for 5 min, from 200 to 240°C at 6°C/min, 240 °C for 5 min.The sample contained saturated hydrocarbons hentriacontane, octacosane, hexacosane, tetratetraacontane, eicosane, nonadecane, which made up greater than 50%, in addition to fatty acids. Octacosane dominated them. The others (~1.3%) consisted of 2-octanone (0.12%) and 4,8,12,16-tetramethylheptadecan-4-olide (1.2%).The root extract was separated by column chromatography over silica gel with elution first by hexane and then by solvent systems hexane:petroleum ether and petroleum ether:CHCl 3 . This isolated five compounds, of which three were identified as triacontane, heptacosane, and lignoceric acid. The structures of the compounds were determined by PMR spectroscopy and comparison of their melting points with those of known compounds.Triacontane. C 30 H 62 , mp 66-68°C. PMR spectrum (400 MHz, CDCl 3 , G, ppm, J/Hz): 0.88 (6H, t, J = 6.7), 1.25 (56H, s) [4].Heptacosane. C 27 H 56 , mp 57-59°C. The PMR spectrum contained a triplet for terminal methyls at 0.88 ppm (J = 6.7 Hz) and a broad singlet for -CH 2 -protons at 1.25 ppm. The total number of protons was half of the theoretically calculated amount because of the symmetry of heptacosane. A comparison of the melting point of the sample and the literature established that the compound was heptacosane.PMR spectrum (400 MHz, CDCl 3 , G, ppm, J/Hz): 0.88 (6H, t, J = 6.7), 1.25 (50H, br. s). Lignoceric Acid (24:0). C 23 H 47 COOH, mp 77-79°C [5]. Thus, the fatty-acid and hydrocarbon compositions in E. integrifolius were determined for the first time. Triacontane, heptacosane, and lignoceric acid were isolated.

Hexane Extract of Echinops spinosissimus Turra subsp. spinosus from Tunisia: A Potential Source of Acetylated Sterols – Investigation of its Biological Activities

“…Oleic (61.14%), palmitic (21.36%) and linoleic (10.45%) acids, all together, composed around 92% of the total fatty acids of E. s. spinosus hexane extract. Results on the fatty acid composition reveal that our extract is different from those primary fatty acids isolated from E. sphaerocephalus and E. bannaticus were linoleic (76.7 – 70.2%), oleic (14.1 – 20.8%) and palmitic (6.06% – not described) acids, respectively, whereas, the palmitic acid was the principal acid in the fatty acid composition of E. integrifolius . This could be due to genetic factors and environmental conditions.…”

“…Results on the fatty acid composition reveal that our extract is different from those primary fatty acids isolated from E. sphaerocephalus and E. bannaticus were linoleic (76.7 -70.2%), oleic (14.1 -20.8%) and palmitic (6.06%not described) acids, respectively, [17] whereas, the palmitic acid was the principal acid in the fatty acid composition of E. integrifolius. [20] This could be due to genetic factors and environmental conditions. The studied extract was characterized by a polyunsaturated/saturated (P/S) ratio of 0.44 inferior to that of olive oil (0.92).…”

The Genus Echinops: Phytochemistry and Biological Activities: A Review

“…integrifolius indicated the presence of methyl esters of fatty acids as well as saturated hydrocarbons such as octacosane, hentriacontane, hexacosane, tetratetraacontane, eicosane, and nonadecane. Trace amount of 2-octanone and 4,8,12,16-tetramethyl heptadecan-4-olide were also detected in E. integrifolius (Karimov and Aisa, 2013).…”