Fatty acid and triacylglycerol composition of seed and pericarp oils of the medicinal crop Withania somnifera (L.) Dunal cultivated in Sardinia (Italy)

We studied the chemical composition and the nutritional properties of fixed oils extracted from seeds and pericarps of the medicinal plant Whitania somnifera. W. somnifera wild germplasm was collected in Sardinia (Italy) and cultivated in Campidano subregion (Southern Sardinia). The main fatty acids of seed oil were 18:2 n-6 (53%, 73.6 mg/g of dry weight), 18:1 n-9 (21%, 29.3 mg/g of dry weight), 16:0 (19%), and 18:0 (4%). Trilinolein and dilinolein derivatives represented the main seed oil triacylglycerols. Linoleic (40%, 67.7 mg/g of dry weight), oleic (29%, 48.7 mg/g of dry weight), palmitic (22%), stearic (4%) and α-linolenic (3%), were the main fatty acids in pericarp oil, with higher total level of monounsaturated fatty acids than seed oil, while monolinolein and dilinolein derivatives represented the main triacylglycerols. The results of this study qualify Sardinian W. somnifera berries as an interesting source of oils with nutritional properties.