Study on cellulase enzymatic hydrolysis of microwave acid pretreated corn stalk | 微波酸预处理玉米秸秆纤维素酶水解条件研究

Chinese. 将预处理过的玉米秸秆的髓、皮和叶子分别进行纤维素酶解处理, 确定纤维素酶水解预处理后玉米秸秆不同部分的最适条件，找出最适合做燃料酒精原料的部分。分别对微波酸预处理后的玉米秸秆髓、叶子、皮纤维素酶水解的酶用量、pH值、温度、时间4个因素进行单因素试验和正交试验，并对正交试验结果进行验证。4个因素对玉米秸秆髓、叶子和皮纤维素酶酶解的影响顺序均为酶用量温度时间pH。玉米秸秆髓、叶子和皮的最佳纤维素酶酶用量分别为3 000，3 500，4 000 U/g，最佳温度分别为44，44，47 ℃，最佳水解时间分别为 84，96，96 h，最佳pH分别为5.2，5.4，5.4，在最佳水解条件下，水解液中还原糖含量分别为3.468 7，3.101 6， 1.828 1 mg/mL。玉米秸秆的髓和叶子适合制备燃料酒精，秸秆皮所用的纤维素酶酶用量最大，但水解液中还原糖含量最低，不适合作燃料酒精的原料。

English. Pretreated corn stalk leaf, skin and core were investigated by cellulase hydrolysis respectively to confirm the optimal hydrolysis condition of different parts of pretreated corn stalk, and select the most suitable part for the fuel-ethanol. The effect of each factor was investigated by single factor experiment and orthogonal experiment, and the result of orthogonal experiment was confirmed by the verification experiment. The effect order of the four factors mentioned above to enzymatic hydrolysis of pretreated corn stalk was shown as enzyme-loadtemperaturetimepH. The optimal enzyme-load of the corn stalk core, leaf and skin was 3 000, 3 500 and 4 000 U/g, while the optimal temperature was 44, 44 and 47 ℃, the optimal time 84, 96 and 96 h, and the optimal pH 5.2, 5.4 and 5.4 respectively. The sugar content of the hydrolysis under the optimal enzymatic hydrolysis condition of the corn stalk core, leaf and skin was 3.468 7, 3.101 6 and 1.828 1 mg/mL. The corn stalk cores and leaves are suitable for the fuel-ethanol production, but the corn stalk skin is not the suitable substance for producing fuel ethand.