Preferential extractability of γ -oryzanol from dried soapstock using different solvents

BACKGROUND: γ -Oryzanol from rice bran has lately gained potential importance because of its proven health benefits. Thus
the extractability of γ -oryzanol from the soapstock of crude rice bran oil is important from the perspective of future large-scale
production, which would give value addition to this by-product obtained from the rice bran oil industry. The aim of the present
study was to investigate the extraction of γ -oryzanol from the drum-dried soapstock of rice bran oil using various solvents.
RESULTS: Itwasfoundthat γ -oryzanol couldbe extractedmost effectively usingethyl acetate, followedbydichloromethaneand
ethyl methyl ketone. All components of γ -oryzanol have an alcohol group in the ferulate portion giving rise to relatively high
polarity, thereby increasing the extraction in more polar solvents efficiently. Ethyl acetate showed maximum extractability of
γ -oryzanol by the Soxhletmethod. To quantify γ -oryzanol, reverse phase high-performance liquid chromatography (RP-HPLC)
was used for fingerprinting the γ -oryzanol analogues with respect to standard γ -oryzanol.
CONCLUSION: A new RP-HPLC method for determining the individual components of γ -oryzanol has been reported that can be
used for performing an online characterisation of γ -oryzanol analogues by liquid chromatography/mass spectrometry.