Comparison of isopropanol and hexane for extraction of vitamin E and oryzanols from stabilized rice bran

The effects of solvent-to-bran ratio (2:1 and 3:1, w/w), extraction temperature (40 and 60 degrees C), and time (5, 10, 15, 20, and 30 min) were studied for hexane and isopropanol extraction. Increasing the solvent-to-bran ratios and extraction temperature increased the amounts of crude oil, vitamin E and oryzanol recovered for both solvents. An extraction time of 15 min was sufficient for optimum crude oil, vitamin E and oryzanol extraction. Preheated isopropanol (3:1 solvent/bran ratio and 60 degrees C) extracted less crude oil (P > .05) but more vitamin E (P < .05) and similar amounts of oryzanol (P > .05) relative to preheated hexane. The data suggest that isopropanol is a promising alternative solvent to hexane for extraction of oil from stabilized rice bran.