Fatty Acids, Tocopherol, and Sterol Contents of Some Nigella Species Seed Oil

The lipid compositions of the seed oils of some Nigella species were investigated. The total oil content of the seeds ranged from 28.0 to 36.4%. GC-MS fatty acid compositional analysis of the Nigella seed oils revealed the content of linoleic acid to be the highest (40.3-58.9%). Other prominent fatty acids were as follows: oleic (18.7-28.1%), palmitic (10.1-12.5%), 22: 1 D11 (3.2-3.8%) and stearic (2.6-3.1%) acids. All the Nigella seed oils analysed exhibited differences in their tocopherol contents and the differences were estimated. The oils extracted from the seeds contained between 1.70-4.12 mg/100 g alpha-T, 0.97-4.51 mg/100 g gamma-T, and 4.90-17.91 mg/100 g beta-T3. The total tocopherol content in seeds varied between 9.15 mg/100 g to 24.65 mg/100 g. The compositions of the sterol fractions were determined by gas liquid chromatography. The total amounts of sterols ranged between 1993.07 mg/kg to 2182.17 mg/kg. The main component was beta-sitosterol (48.35-51.92%), followed by 5-avenasterol, campesterol, and stigmasterol.