Phytochemical analysis on rice bran and its pitch was performed by the tool of TLC, UV- and IR-spetroscopy, so that it was found that they contained {gamma}-oryzanol and free sterol. GC-MS analysis of free sterol revealed that it was composed of {beta}-sitosterol, campesterol and stigmasterol. Successive phytochemical analysis of {gamma}-oryzanol revealed that it was composed of ferulic acid ester of triterpene and sterol, respectively. Triterpene moieties of {gamma}-oryzanol were identified as follows: cycloartanol, cycloartenol, 24-methylenecycloartanol and unknown triterpene; And sterol moieties were found to be identical with free sterols. In addition, characteristic absorption band in UV spectrum (220-340 nm) was exclusively due to {gamma}-oryzanol. Thus, it was suggested that rice brans of nearly all species of Oryza sativa can be quantitatively analyzed by UV absorption spectrometry, even when water soluble pigments was contained in the rice bran.
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