固定化枯草芽孢杆菌发酵生产捷安肽素

Jiean-peptide Prodution by Immobilized Cell Fermentation of Bacillus subtilis

采用吸附固定化细胞技术发酵生产捷安肽素.首先对7种不同的吸附性固体载体进行筛选,发现木屑作为载体效果最好;然后通过正交优化实验和单因素实验确定载体木屑的最佳条件为:粒度0.5～0.6mm,添加浓度10gL-1发酵液.为避免吸附法固定的菌体细胞从载体上脱落,尝试在木屑固定化细胞体系中加入粘稠剂以增强吸附性能,运用单因素实验确定了粘稠剂的种类和浓度,即为15gL-1海藻酸钠.最后应用响应面方法优化固定化细胞发酵培养基及培养条件,结果表明:接种量为10%、黄豆粉水解液总氮浓度为1.7gL-1发酵液、葡萄糖浓度为33.7gL-1发酵液时捷安肽素的生物效价最大,达到7282.08U,比非固定化细胞培养提高了53.9%.

The paper described a novel method for adsorption and application of immobilized cells for Jiean-peptide production. Seven absorptive solids were chosen as the candidate carriers for immobilization of Bacillus subtilis cells and among them wood chips were identified as the best. The optimal conditions of wood chips as B. subtilis cells＇ carriers were 0.5~0.6 mm in diameter and 10 g L^-1 in fermentation broth, which were determined through single factor and orthogonal experiments. In order to avoid the detachment of the immobilized B. subtilis cells from the carriers, different adhesive agents were added into the wood chips to increase its absorption, and 15 g L^-1 sodium alginate gel was found to be the best by single factor experiment. Then the optimal fermentation media and conditions were obtained by response surface methodology： 10% inocula, 1.7 g L^-1 total nitrogen of soymeal hydrolysate and 33.7 g L^-1 glucose in fermentation broth. Under these conditions, the biological potency of Jiean-peptide peaked as high as 7 282.08 U, which was 53.9% higher than that in carrier-free liquid cultivation. Fig 3, Tab 7, Ref 17