微波预处理结合复合酶水解蔗渣

摘要

蔗渣是蔗糖加工废弃物，微生物利用蔗渣水解物作为碳源进行发酵可生产乙醇、乳酸等能源物质和化工原料，具有重要应用价值．采用微波加热结合酸碱处理工艺破坏蔗渣致密结构并去除木质素，比较4种商品纤维素酶对经预处理的蔗渣的酶解效果．最后针对蔗渣的复杂结构采用了复合酶酶解工艺．结果表明将蔗渣按1∶50固液比，在微波功率为280 w下加热，先于1％NaOH处理10 min，然后再于1％H2 SO4处理5 min可有效破坏蔗渣的致密结构，去除部分木质素．采用的4种商品纤维素酶中，Yacult R-10纤维素酶酶解效果最好，最佳酶解条件为添加4000 U/g预处理蔗渣，pH5.5，温度50℃，酶解时间12 h．采用复合酶组合（纤维素酶，果胶酶，木聚糖酶和半纤维素酶12∶2∶3∶5）酶解蔗渣得到酶解液总葡萄糖质量浓度为5.99 g/L．%Sugarcane baggasse is the byproduct of sugar making.Hydrolysate of sugarcane baggasse can be utilized by microorganisms to produce biofuel or chemicals.In this study,baggasse was pretreated sequentially with acid and alkali under microwave irradiation to remove lignin and destroy the compacted structure.Multi-enzymes were applied to hydrolyze the baggasse.Results shown that lignin can be effec-tively removed under microwave power of 280 w by fist treatment 1%NaOH for 1 0 min,and then in 1%H2 SO4 for 5 min.Among four commercial cellulases,Yacult R-1 0 was found to hydrolyze the baggasse most effectively.The best productivity of total reducing sugar can be achieved by addition of 4 000 U cel-lulase/g pretreated baggasse and pH5.5 and 50 ℃ for 1 2 h.Glucose concentration of 5.99 g/L was a-chieved by addition of multi-enzymes (cellulase∶pectinase∶xylanase∶hemicellulase 1 2∶2∶3∶5 ).