IDENTIFICATION AND QUANTITATION OF GAMMA-ORYZANOL COMPONENTS AND SIMULTANEOUS ASSESSMENT OF TOCOLS IN RICE BRAN OIL

A reverse-phase high-performance liquid chromatography method was developed for the simultaneous separation and quantitation of tocopherols, tocotrienols and oryzanols present in rice bran oil. Tocopherols and tocotrienols were quantitated by fluorescence detection and oryzanols (ferulic acid esters of sterols and triterpene alcohols) by photodiode array detection. Chemical ionization mass spectrometry was used to identify cycloartenyl ferulate, 24-methylene cycloartanyl ferulate, campesteryl ferulate, beta-sitosteryl ferulate and cycloartanyl ferulate as the major oryzanols separated by this procedure. The levels of these nutritionally significant components were found to vary in fully processed, edible rice bran oils from different manufacturers.