Composition and Functionality of Nigella sativa Fixed Oil

Black cumin seed contains fixed oil (35.6–41.6%). Besides the high oil content, black cumin seed oil (BCSO) is rich in essential fatty acids, as well as bioactive sterols (ST) and tocols with functional properties. The fatty acid profile is dominated by unsaturated fatty acids especially polyunsaturated fatty acids (59.7%), followed by monounsaturated fatty acids (24.1%), and saturated fatty acids (16.1%). The major polyunsaturated fatty acid is linoleic acid, which comprises approximately half of the fatty acid composition, while oleic acid is the main monounsaturated one (24.1%). As for the tocols profile, BCSO contains a high level of β-tocotrienol (1195 mg/kg), and γ-tocopherol isomer (208 mg/kg). β-sitosterol is the dominant sterol compound from the unsaponifiable fraction of BCSO (1135–1182 μg/g oil). Major phospholipids subclasses in BCSO are phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidylinositol. Phenolic compounds that exhibit strong antioxidant effect, are rich in BCSO with amounts ranging from 1.02 to 1.40 mg gallic acid equivalents/g oil. Besides, BCSO contains about 3.48–8.73 mg/g thymoquinone and a trace amount of dithymoquinone which contribute to human health.