title: Fat-soluble bioactive components in colored rice varieties.
abstract: Bioactive components in rice vary depending on the variety and growing condition. Fat-soluble components such as γ-oryzanol, tocopherols, tocotrienols, carotenoids, and fatty acids were analyzed in brown, sugary brown, red, and black rice varieties using established high-performance liquid chromatography (HPLC) and GC methodologies. In addition, these colored rice varieties were further analyzed using a high-resolution liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) (LTQ-Orbitrap XL) to identify the [M-H](-) ions of γ-oryzanol, ranging from m/z 573.3949 to 617.4211. The highest content of tocopherols (α-, 1.5; γ-, 0.5 mg/100 g) and carotenoids (lutein 244; trans-β carotene 25 μg/100 g) were observed in black rice; tocotrienols (α-, 0.07; γ-, 0.14 mg/100 g) in red rice, and γ-oryzanol (115 mg/100 g) in sugary brown rice. In all colored rice varieties, the major fatty acids were palmitic (16:0), oleic (18:1n-9), and linoleic (18:2n-6) acids. When the γ-oryzanol components were further analyzed by LC-MS/MS, 3, 10, 8, and 8 triterpene alcohols or sterol ferulates were identified in brown, sugary brown, red, and black rice varieties, respectively. Such structural identification can lead to the elucidation of biological function of each component at the molecular level. Consumption of colored rice rich in beneficial bioactive compounds may be a useful dietary strategy for achieving optimal health.
authors.affiliation: 1 Jean Mayer USDA-Human Nutrition Research Center on Aging, Tufts University , Boston, Massachusetts, USA .
authors.forename: Igor Otavio
authors.initials: IO
authors.lastname: Minatel
authors.forename: Sang-Ik
authors.initials: SI
authors.lastname: Han
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Aldini
authors.forename: Mara
authors.initials: M
authors.lastname: Colzani
authors.forename: Nirupa R
authors.initials: NR
authors.lastname: Matthan
authors.forename: Camila Renata
authors.initials: CR
authors.lastname: Correa
authors.forename: Denise
authors.initials: D
authors.lastname: Fecchio
authors.forename: Kyung-Jin
authors.initials: KJ
authors.lastname: Yeum
mesh_terms: D002338:Carotenoids / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003116:Color; D005227:Fatty Acids / Q000737:chemistry; D012275:Oryza / Q000737:chemistry* / Q000145:classification; D010666:Phenylpropionates / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry / Q000145:classification
chemical_list: D005227:Fatty Acids; D010666:Phenylpropionates; D010936:Plant Extracts; D002338:Carotenoids; C013172:gamma-oryzanol
keywords: LC-MS/MS; carotenoid; informatics; lutein; oryzanol; tocopherol