Properties of extract obtained from defatted rice bran by extraction with aqueous ethanol under subcritical conditions

Abstract

Defatted rice bran was treated with water or aqueous ethanol under subcritical conditions to recover materials with antioxidative activity. The extraction conditions, namely ethanol concentration (10 - 100% (v/v)), temperature (120 - 237°C) and time after attainment of a desired temperature (5 - 60 min), were studied. On the basis of the determinations of total carbohydrate, protein and phenolic contents, yield, DPPH radical scavenging activity, and antioxidative activity against oxidation of bulk linoleic acid, the extraction with 20% (v/v) ethanol at 237°C for 5 min was concluded to be comparatively more efficient than that by subcritical water at the same extraction temperature for the same length of time.