Phytochemical characterization of potential nutraceutical ingredients from Evening Primrose oil (Oenothera biennis L.)

Abstract

Evening Primrose oil (EPO) is a natural product extracted by cold-pressed from Oenothera biennis L. seeds. EPO is widely used as a dietary supplement from which beneficial effects have been reported in rheumatic and arthritic conditions, atopic dermatitis, psoriasis, premenstrual and menopausal syndrome, and diabetic neuropathy. The beneficial effects of EPO are thought to be due to its γ-linolenic acid content; in contrast, little effort has been expended to characterize the non-triglyceridic constituents of EPO. In order to evaluate its potential as source of functional food ingredients our aim in this work has been identified and quantified the different components of EPO by different techniques (GC–MS and HPLC). The lipid profile showed that oleic (7%), linoleic (74%) and γ-linolenic (9%) were the most abundance fatty acids. Unsaponifiable matter and subfractions were obtained by CEE/2568/91. Separation of the compounds under study was achieved giving a reasonable analysis time and good resolution. A yield (1.82–1.95%) of unsaponifiable matter was obtained and levels of saturated hydrocarbons (0.291.97±14.85mg) were noticed. β-Sitosterol (7952.00±342.25mg/kg oil) and campesterol (883.32±0.45mg/kg oil) were predominant in phytosterol fraction (9573mg/kg oil), while tetracosanol (236.93±2.32mg/kg oil) and hexacosanol (289.92±3.41mg/kg oil) in linear aliphatic alcohol fraction (798.04±5.66mg/kg oil). In the phenolic fraction (55.49±2.76mg/kg oil), ferulic acid (25.23±2.64mg/kg oil) was the major component. From the results obtained, it can be suggested that the Evening Primrose oil can be considered an interesting alimentary source of substances of nutraceutical value.