MODIFICATION OF RICE STRAW BY STEAM EXPLOSION AND ENZYMATIC SACCARIFICATION OF STEAM-EXPLODED PRODUCTS

Steam explosion is one of the effective pretreatment methods for enzymatic saccharification of plant biomass. Rice straw was treated with high-pressure steam (2.55, 3.04, 3.53 and 4.02MPa) for 0.5 approximately 10 min. The exploded rice straw was separated into water-soluble hemicellulose, holocellulose, methanol-soluble lignin and Klason lignin. Effects of this preteatment on the characteristics of exploded rice straw were studied from experimental data of pH and pore size distribution of exploded material, amounts of extractive components and enzymatic saccharification. The enzymatic saccharification increased with increasing amount of methanol-soluble lignin. The saccharification of the exploded rice straw was expressed as a function of steam pressure and steaming time. It was estimated from the equation that maximum saccharification was obtained at a steam pressure from 3.3 to 3.8MPa and a steaming time of 1.0 to 3.5 min.