光固化聚乙二醇水凝胶及其固定化枯草杆菌的研究

Study on the Photocrosslinked Poly(ethylene glycol) Hydrogel and Its Immobilized Bacillus Substilis

制备了一系列光固化聚乙二醇水凝胶固定化载体，研究了该水凝胶的结构、性能及其固定化枯草杆菌发酵产出α－淀粉酶的特性。结果表明，用水凝胶作载体制备的固定化枯草杆菌具有强度高、对温度和酸碱度变化的适应性强、贮存及重复使用性能好等优点。而且其产出α－淀粉酶的活力比相应的游离细胞高出２０％ 以上。固定化细胞半连续发酵１７批，历时３７天，产酶活力仅下降２０％。基本能达到实际应用的要求。

series of photocrosslinked poly(ethylene glycol) hydrogels (PPEG) were prepared and used as carriers for immobilization of bacillus substilis. The structure and properties of PPEG and the feature of PPEG immobilized Bacillus substilis to produce α-amylase were investigated. It is found that the immobilized cells are superior to corresponding free cells in respect to the ability to produce α-amylase and stabilities to temperature, PH, and storage. Also the immobilized cells have very good mechanical and batch fermentation properties. The activity of α-amylase produced by the immobilized cells is about 20% higher than the free cells, and after semi-continuous batch fermentation for 17 times, its activity decreases only about 20%.