Content of gamma-oryzanol and composition of steryl ferulates in brown rice (Oryza sativa L.) of European origin.
The content of gamma-oryzanol and the composition of steryl ferulates were determined in brown rice of European origin using on-line coupled liquid chromatography-gas chromatography (LC-GC). Analysis of 30 brown rice samples of various cultivars, grown at different sites and in different seasons, revealed the gamma-oryzanol content to range from 26 to 63 mg/100 g. Cycloartenyl ferulate and 24-methylenecycloartanyl ferulate were the major components of gamma-oryzanol followed by campesteryl ferulate, campestanyl ferulate, and beta-sitosteryl ferulate. The proportions of individual steryl ferulates exhibited enormous variability. However, irrespectively of the great variations observed for single steryl ferulates, the proportions of the sum of 4,4'-dimethylsteryl ferulates (cycloartenyl ferulate, 24-methylenecycloartanyl ferulate) and the sum of 4-desmethylsteryl ferulates (campesteryl ferulate, campestanyl ferulate, and beta-sitosteryl ferulate) were rather constant. The significant natural variability observed for gamma-oryzanol content and composition of steryl ferulates were shown to be influenced by environmental conditions but not by the degree of maturity of rice grains.
Miller
Andreas
A
Technische Universität München, Lehrstuhl für Allgemeine Lebensmitteltechnologie, Am Forum 2, D-85350 Freising-Weihenstephan, Germany.
Engel
Karl-Heinz
KH
D002849:Chromatography, Gas; D002853:Chromatography, Liquid; D003373:Coumaric Acids / Q000032:analysis*; D004777:Environment; D005060:Europe; D012275:Oryza / Q000737:chemistry*; D010666:Phenylpropionates / Q000032:analysis*; D010840:Phytosterols / Q000032:analysis*; D012639:Seeds / Q000737:chemistry* / Q000254:growth & development
D003373:Coumaric Acids; D010666:Phenylpropionates; D010840:Phytosterols; C004999:ferulic acid; C013172:gamma-oryzanol