羽毛降解菌株的筛选及其发酵条件的优化

Isolationof a Keratin-Degrading Bacillus and Its Optimization of Fermentation Conditions

从长期堆积腐烂鸡毛的土壤中分离、筛选、纯化出1株能够高效降解羽毛角蛋白的菌株。该菌为杆状、内生孢子、革兰氏染色阳性;以羽毛为唯一的碳源和氮源,研究了发酵条件对该菌株降解羽毛生产可溶性蛋白的影响,通过对单因素实验及正交优化试验,确定了该菌株最佳发酵条件为3%的接种量时,添加6g/150mL的羽毛量、初始pH 11.0、30℃下摇床发酵7d后,获得的发酵液中可溶性蛋白最大浓度为34.375g/L。

A keratin‐degrading bacillus was isolated from the soil of decayed feather .The isolate was rod‐shaped ,endospore and gram‐positive .The effects of fermentation conditions on the strain degrading feather and soluble protein yield were studied while feather as the sole source of carbon and nitrogen in the medium .The optimal parameters for the fermentation conditions producing the soluble protein were investigated by the single‐factor tests and orthogonal optimization experimentation . The optimal fermentation conditions were determined ,when the inoculum size 3% ,the amount of feathers 6 g/150 mL and initial pH 11.0 , under 30 ℃ after 7 d in shaker ,the soluble protein yield was 34.375 g/L in fermentation liquid .