Fatty Acid Composition and Health Benefits of Some Seed Oils of Emerging Interest

The fatty acid composition of some seed oils from plants of emerging interest was studied. The benefits towards human health were evaluated by taking into account current recommendations regarding dietary intake of essential, polyunsaturated, and monounsaturated fatty acids and by discussing the pathologies for which such fatty acids exert protective action. Species studied were Hemp (Cannabis sativa), Flax (Linum usitatissimum), Milk Thistle (Silybum marianum), Perilla (Perilla frutescens), Borage (Borago officinalis), and Black Cumin (Nigella sativa). Seeds were subjected to cold milling in order to maintain their original nutritional characteristics. Chemical analyses were performed via the dual-detector gas chromatography technique by means of Flame Ionization Detection (FID) and mass spectrometry (MS) and by applying a modified version of the AOAC Official Method 991.39, thanks to which it was possible to obtain the fatty acid composition expressed as mg per gram of oil: such information is not always available in the literature for the species studied here. Comparison with the fatty acid international guidelines about the recommended intakes in g/day was made. This allowed us to evaluate whether such oils are suitable to be used as fatty acid food supplements to rebalance the Western diet, which is shown to be inadequate by numerous studies. Results show that seed oils from Cannabis sativa, Linum usitatissimum, and Perilla frutescens are suitable to be used as food supplements while seed oils from Silybum marianum, Borago officinalis, and Nigella sativa are not. It is important to note that any possible benefits from other parts of the plant (leaves, stems, flowers, and roots) are not studied or questioned by the present research, which focuses solely on fatty acids in the oil extracted from the seeds.