Application of Subcritical Water Treatment for Production of Phenolic Compounds from Rice Bran Biomass

摘要

This study deals with the production of phenolic compounds from decomposition of rice bran biomass under subcritical water condition. Experiments were performed in a batch stainless steel vessel over a wide temperature ranging from 373 to 633 K for 10 min. The main identified and quantified phenolic compounds were caffeic acid, ferulic acid, gallic acid, p-coumaric acid, p-hydroxybenzoic acid, protocatechuic acid, syringic acid, vanillic acid and, vanillin. In addition, the antioxidant activity of aqueous solution were also evaluated. Both phenolic compounds and antioxidants showed increasing with temperature rising, and leveled off at the temperatures higher than 493 and 553 K, respectively. It was also realized that due to acidic properties of produced compounds, autocatalysis may occur during subcritical water treatment of rice bran.