title: Quantification of tocopherols, tocotrienols, and γ-oryzanol contents and their distribution in some commercial rice varieties in Taiwan.
abstract: The eight vitamin E isomers [α-, β-, γ-, and δ-tocopherols (T) and α-, β-, γ-, and δ-tocotrienols (T3)] and γ-oryzanol are known to possess diverse biological activities. This study examined the contents of these compounds and their distribution in 16 commercial rice varieties in Taiwan. Results showed that the order of vitamin E, total T, total T3, and γ-oryzanol contents was rice bran > brown rice > rice husk > polished rice. γ-T3 was the highest vitamin E isomer present in all rice samples, while β-T, β-T3, δ-T, and δ-T3 were present in trace amounts. The Japonica varieties contained a higher total T, total T3, and γ-oryzanol than the Indica varieties. They also have a higher level of α-T and α-T3 but a lower level of γ-T and γ-T3 than the Indica varieties. However, no obvious difference in total T, total T3, and γ-oryzanol content was noted between black- and red-colored rice varieties.
authors.affiliation: Department of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan.
authors.forename: Shao-Hua
authors.initials: SH
authors.lastname: Huang
authors.forename: Lean-Teik
authors.initials: LT
authors.lastname: Ng
mesh_terms: D012275:Oryza / Q000737:chemistry*; D010666:Phenylpropionates / Q000032:analysis*; D012639:Seeds / Q000737:chemistry*; D013045:Species Specificity; D013624:Taiwan; D024505:Tocopherols / Q000032:analysis*; D024508:Tocotrienols / Q000032:analysis*
chemical_list: D010666:Phenylpropionates; D024508:Tocotrienols; D024505:Tocopherols; C013172:gamma-oryzanol