REGIONAL DISTRIBUTION IN THE FATTY ACIDS OF TRIACYLGLYCEROLS AND PHOSPHOLIPIDS OF SESAME SEEDS (SESAMUM INDICUM)

Abstract

ABSTRACT The fatty acid distribution of triacylglycerols (TAGs) and major phospholipids (PLs) in sesame (Sesamum indicum) seeds was investigated in relation to the endogenous antioxidants. γ‐Tocopherol was present in the highest concentration, and δ‐ and α‐tocopherols were found in very small amounts. Sesamin and sesamolin were the main lignan components. The lipids extracted from three cultivars were separated by thin‐layer chromatography. The major lipid components were TAGs and PLs, while steryl esters, free fatty acids and sn‐1,3‐ and sn‐1,2‐diacylglycerols were also present in minor proportions. Significant differences (P < 0.05) in fatty acid distribution existed when different sesame seed cultivars were examined. However, the principal characteristics of the fatty acid distribution in the TAGs, as well as the major PLs, were evident among the three cultivars; unsaturated fatty acids were predominantly concentrated in the sn‐2‐position, and saturated fatty acids primarily occupied the sn‐1‐ or sn‐3‐position. These results suggest that there are no essential differences (P > 0.05) in the oil components among three cultivars.PRACTICAL APPLICATIONSThis paper describes the fatty acid compositions of glycerides, particularly the positional distribution of the fatty acids of triacylglycerols along with those of the main PL in sesame seeds in relation to the endogenous antioxidants. These results were similar to the positional fatty acid distributions in the lipid classes of peanut, corn and soybeans among the plants seeds in the literature, and suggest that there are no essential differences (P > 0.05) in the oil components among the three cultivars. The data obtained would be contributed to both producers and consumers to investigate the functional properties of sesame seed oil.