High-performance liquid chromatography determination of tocopherols in wheat bran

Abstract

Natural vitamin E is significant phytochemical compound with antioxidant activity and potential benefit for human health. The physiological role of vitamin E is in its ability to react with free radicals in cell membranes and preventing lipid peroxidation. Vitamin E is composed of eight different structurally related compounds, vitamers (a-, B-, y- and 65-tocopherols and a-, B-, y- and otocotrienols) which are known to occur in nature. Among cereals, wheat grain and wheat bran represent rich sources of tocopherols. The aim of this study was to investigate tocophérols composition (a-, B-, y- tocopherols) in selected 20 wheat genotypes. The samples consisted the bran portion of the outer layer of wheat grain that were the by-product of milling on the MLU 202 laboratory flour mill. Tocopherols were determined in the wheat bran samples by using the simple analytical method which includes extraction with hexane and normalphase high-performance liquid chromatography with fluorescence detection. The mobile phase consisted a mixture of hexane:ethyl acetate (70:30, viv). Total tocopherols content in wheat bran extracts ranged from 28.08 in cv. Partizanka to 107.49 mg/kg in cv. Skopljanka The average contents of a-, B- and ytocopherols were in the range from 3.16 (a-tocopherol in cv. Partizanka) to 81.04 mg/kg (y- tocopherol in cv. Skopljanka). Major vitamers for those tested genotypes were a- and y- tocopherols. The results have shown that there were significant differences in tocopherols composition and content among the genotypes, indicating the great genetic potential for improvement. ords: Sulfor. finociception.