Cellulolytic enzyme production from agricultural residues for biofuel purpose on circular economy approach

This study evaluated the production of cellulolytic enzymes from different agricultural residues. The crude enzyme extract produced was characterized and applied for saccharification of some agricultural residues. Maximum cellulolytic activities were obtained using soybean hulls. All enzymatic activities were highly stable at 40 degrees C at a pH range of 4.5-5.5. For stability at low temperatures, the enzyme extract was stored at freezing temperature and cooling for about 290 days without major loss of activity. The K-m values found for total cellulase (FPase), endoglucanase (CMCase), and xylanase were 19.73mgml(-1), 0.65mgml(-1), and 22.64mgml(-1), respectively, and V-max values were 0.82molmin(-1)mg(-1), 0.62molmin(-1)mg(-1), and 104.17molmin(-1)mg(-1) to cellulose, carboxymethyl cellulose, and xylan, respectively. In the saccharification tests, the total amount of total reducing sugars (TRS) released from 1g of soybean hulls catalyzed by the enzymes present in the crude enzyme extract was 0.16gg(-1) dry substrate.