Abstract
Sterol content was determined in the unsaponifiable matter of cereals (5 items), potatoes (5 items), seeds and nuts (7 items), pulses (7 items), olive oil and cotton-seed oil. The ratio of the content of free sterol to that of sterol ester was determined by fractionation on silica gel column. The sterol portion separated by thin layer chromatography was analyzed by gas-liquid chromatography.
The sterol content of 1g lipid was 40-80mg with cereals, ca. 100mg with potatoes and below 15 mg with seeds and nuts, except with chestnut (54mg), and remarkably small amount (below 2mg) with walnut. In pulses it was 40-80mg, except in soybeans (8mg) and in mung-beans (14mg). Olive oil and cotton-seed oil were found to contain 5 and 6mg sterol per gram, respectively. The sterol content of rice-bran, sesame and sunflower seed was more than 500mg/100g and it was especially high in rice-bran (1.3g/100g), while that of potatoes was lower than 200mg/100g because of the high water content. Among pulses the sterol content was highest in soybeans (160mg/100g). The content of free sterols was higher as compared to that of sterol esters, except in cereals and sunflower seeds.
Gas-liquid chromatographic analysis demonstrated that β-sitosterol and campesterol were contained in all of the materials examined; stigmasterol was not found in wheat, ginkgo seeds, walnuts, rape-seeds, olive oil and cotton-seed oil; the content of β-sitosterol was higher than those of other sterols in all samples tested except in Azuki-and Sasage-beans, in which its content was nearly equal to that of stigmasterol; brassicasterol was identified in rape-seeds.
A peak on gas-liquid chromatogram coincident to that of cholesterol was found in potato and Sasage-beans and also, though in small content, in wheat, pea-nuts, peas, soybeans and mung-beans. So it is presumable that cholesterol is widely distributed also in plants, though in small amount.
