Vitamin E Profiles and Triacylglycerol Molecular Species of Colored Rice Bran Cultivars at Different Degree of Milling

摘要

The objective of this study was to evalute the tocochromanol distributions, lipid components and molecular species of triacylglycerols (TAG) in three colored rice bran cultivars. The dominant tocochromanol were gama-tocotrienol, alpha-tocopherol and alpha-tocotrienol with smaller amounts of gama-tocopherol, delta-tocopherol and delta-tocotrienol. These lipids comprised mainly TAG (78.0-81.6 wt%), free fatty acids (FFA: 5.6-8.8 wt%), and phospholipids (PL: 6.3-7.0 wt%), while other components were present in minor proportions (0.4-2.3 wt%). Sixteen different TAG molecular species were detected and quantified by successive applications of AgNO 3 -TLC and GC. The major TAG molecular species were SM 2 (6.1-9.8%), S 2 D (4.8-7.3%)?M 3 (16.4-18.7%), SMD (6.2-9.2%), SD 2 (6.5-9.5%), SMT (6.3-7.7%), M 2 D (12.3-15.5%.), MD 2 (8.4-10.4%), SDT (4.3-5.4%) and D 3 (10.2-15.2%) (where S, M, D, and T denote saturated FA, monoene, diene, and triene, respectively). The results showed that colored rice bran lipids contain large amounts of nutraceutical with proven positive health effects.