Sterols of sunflower seeds from different locations in Nigeria.

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), Kaduna
(33.92±0.08; 0.68±0.00) and Minna(31.91±0.05;0.64±0.04) in descending order. There was no significant difference
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.