Composition of Essential Oil Obtained From Tubular, Head and Ligulate Flowers of Calendula officinalis L. by Steam Distillation of Plant Material and CO2 Extracts

Abstract

Essential oil content of tubular, head and ligulate flowers of Calendula officinalis L. were determined using official steam distillation procedure. It was found that the ligulate flower sample had the highest oil content (0.16%). Applying SFE by means of CO2 (200 bar, 40 degrees C, 3 h extraction time), the highest extraction yield was found in tubular and ligulate flower samples (3.67% and 3.64%). Head flower had a lower extraction yield (2.60%) as the result of relatively small content of fatty oil, waxes and resins present in plant material. Steam distillation procedure was applied to obtain essential oils from the CO2 extracts devoid from cuticular waxes and resins. The compositions of oils were determined by GC and GC/MS. The main compounds of all investigated oils were alpha-cadinol (11.7-29.1%), delta-cadinene (3.2-20.3%), gamma-cadinene (1.5-11.4%) and cadina-3,9-diene (0.4-11.2%). The oil samples obtained from the CO2 extracts were found to be more complex containing alpha-gurjunene, beta-caryophyllene, beta-gurjunene, cis-muurola-4(14)-5-diene and alpha-humulene.