Nutraceutical composition, antioxidant activity and hypocholesterolemic effect of a water-soluble enzymatic extract from rice bran

Abstract

This study was designed to characterize the nutraceutical composition of a water-soluble enzymatic extract from rice bran (EERB) and to evaluate its antioxidant and hypocholesterolemic activities. The EERB contains broad functional components in water soluble form such as sterols, tocopherols, tocotrienols, γ-oryzanol and peptides. The antioxidant behaviour of EERB specifically against lipid oxidation was measured in an emulsion prepared with fish oil containing fatty acid very susceptible to oxidation (EPA; DHA 30%); the emulsion shows a stable antioxidant activity, specifically preserving the lipid from peroxidation phenomena and inhibiting the generation of thiobarbituric acid-reactive substances (TBARS) and lipid peroxides. Moreover, the hypocholesterolemic activity was evaluated in male Wistar rats through two different hypercholesterolemic diet models: a reduction in total cholesterol levels and an increase in HDL-cholesterol were found in both models. EERB is a new product from rice bran that can control lipid oxidation in emulsions and induce a physiological hypocholesterolemic effect. These findings may facilitate the development and use of new products derived from rice within the functional food field.