再生丝素蛋白/细菌纤维素复合膜的制备及发酵培养条件优化  

Preparation of Regenerated Silk Fibroin /Bacterial Cellulose Composite Membrane and Optimization of Fermentation Cultural Conditions

作　　者：朱正华[1] 董悦涵[1] 赵潇[1] 周晓红[1] 

机构地区：[1]浙江经贸职业技术学院应用工程系,杭州310018

出　　处：《蚕业科学》2015年第5期940-945,共6页ACTA SERICOLOGICA SINICA

基　　金：浙江省自然科学基金项目(No.LY14C100003)

摘　　要：将再生丝素蛋白加入生产细菌纤维素的发酵液,以木醋杆菌(Acetobacter xylinum)进行静置发酵,利用发酵过程中的较高酸性环境(pH<3.4),使菌株产生的纤维素残基(—OH)与丝素蛋白的残基(—COOH、—NH2)原位聚合,制备新型生物医学材料再生丝素蛋白/细菌纤维素(SF/BC)复合膜。通过单因素试验确定最佳发酵培养时间为10 d,并进一步通过正交试验优化发酵培养基配方为80 g/L果糖、10 g/L酵母粉、2.0 g/L无水硫酸镁、1.0 g/L柠檬酸、10 g/L磷酸氢二钠、30 g/L磷酸氢二钾,培养基初始pH为6.8。在此培养条件下SF/BC复合膜干膜的产量为1.871 5 g/L。扫描电子显微镜观测SF/BC复合膜中细菌纤维素纤维间因丝素蛋白的引入,使得纳米纤维间的孔径增大,而内部含水率也将随着孔径的增大而增加,说明丝素蛋白的引入改善了单一细菌纤维素膜在孔径、含水率等方面的性能,同时也改进了单纯丝素蛋白膜在亲水性、机械性能等方面的不足。In this study,the regenerated silk fibroin was added in fermentation liquid of Acetobacter xylinum producing bacterial cellulose to conduct static fermentation. Through in situ polymerization between cellulose residues（ —OH） produced by A. xylinum and silk fibroin residues（ —COOH and —NH2） under the high acidic environment（ pH3. 4）,a new type of biomedical material,regenerated silk fibroin/bacterial cellulose（ SF/BC） composite membrane,was prepared.Through single factor test and orthogonal test,the optimal culture time was 10 d,and best optimal fermentation medium formula was set as follows： 80 g /L fructose,10 g /L yeast powder,2. 0 g /L anhydrous magnesium sulfate,1. 0g /L citric acid,10 g /L disodium hydrogen phosphate,30 g /L potassium hydrogen phosphate,and the initial pH of medium6. 8. Under this culture condition,the yield of dried SF/BC composite membrane was 1. 871 5 g /L. Scanning electron microscopy observation showed that the introduction of silk fibroin in fibers of bacterial cellulose in SF/BC composite membrane led to the increase of pore size in nanofibers,and water content increased with pore size,indicating that the introduction of silk fibroin improved the properties of single bacterial cellulose membrane such as the pore size and water content,and improved the hydrophilicity and mechanical properties of pure silk fibroin membrane as well.

关 键 词：丝素蛋白 木醋杆菌 发酵 培养基配方 再生丝素蛋白/细菌纤维素复合膜 

分 类 号：TQ920.6[轻工技术与工程—发酵工程]