Sterols of sunflower seeds from different locations in Nigeria

Abstract

Sunflower (Helianthus species) is cultivated for oil production. Analysis of sterol components of sunflower seeds from different locations in Nigeria is presented. Sterols were separated from unsaponifiable fraction by Thin-layer Chromatography and analyzed with gas chromatograph. The result shows the oil and the unsaponifiable oil contents by location, Benue (37.32±0.07;0.82±0.01), Kano(34.57±0.10;0.72±0.01), Bida(34.06±0.09;0.70±0.00), in the oil content of the seed samples but significant difference occurs in the percentage of unsaponifiable oil content. Cholesterol (71.50) was predominant in the leaves surface while β-sitosterol (30.40) was the most abundant sterol in the intracellular portion of the leaves. The combined concentration of unknown sterols varied between 9.4 and 12.03 for the free sterol and between 2.84 and 5.81 for the sterol ester. Cholesterol/stigmasterol and cholesterol/β-sitosterol ratios were found to be agronomically and geographically related. Significant difference occurred in unknown sterol esters/known sterols esters ratio. This study showed that the chemistry of sunflower seeds is not agronomic and geographically dependent and that the stigmasterol, campesterol and β-sitosterol are significant phytosterols in sunflower. Unidentified sterols component is abundant enough to influence the health benefits of the sunflower oil positively or negatively.