H_2O_2催化预处理对玉米芯酶解的影响

Effect of catalyzed H_2O_2 pretreatment on the enzymatic hydrolysis of corn cob

木糖通常经半纤维素水解而得,而富含半纤维素的玉米芯细胞中同时也含有木质素与纤维素,与半纤维素紧密缠绕,阻碍了其水解,因此预处理便成了生产木糖过程中的一个必要的步骤。经实验优化所得预处理最佳工艺条件为:室温,固-液比1∶20,pH5.0,H2O2量3.05%,Fe2+添加量0.15g,处理时间2.56h。在此条件下H2O2催化预处理后,用木聚糖酶进行酶解,木糖和葡萄糖得率分别比未处理的0.1895、0.1672g/g玉米芯提高到0.2676、0.2930g/g玉米芯。而经木聚糖酶和纤维素酶(双酶)进行酶解后又分别提高到0.2856、0.3321g/g玉米芯,证明H2O2催化预处理是一种有效可行的预处理方法。

Xylose is usually obtained by the hydrolysis of hemi-cellulose. But the existing of lignin and cellulose, which are intertwining with hemi-cellulose in corn cob hinders the hydrolyzing process. So pretreatment becomes a necessary procedure for xylose producing. The optimized conditions were obtained as follow： room temperature,solid-to-liquid ratio was 1：20, pH5.0, H2O2 concentration was 3.05% ,additive amount of Fe^2＋ was 0.15g,and pretreatment time was 2.56h. After this catalyzed H2O2 pretreatment,the xylanase hydrolysis yield of xylose and glucose had reached 0.2676,0.2930g/g corncob,and the yield of un-pretreated corncob was 0.1895 , 0.1672g/g. While cellulase was added ,the yield of xylose and glucose came up to 0.2856,0.3321g/g. It was proved that catalyzed H2O2 pretreatment was an effective and feasible pretreatment.