长双歧杆菌发酵培养基的优化

目的对长双歧杆菌液态发酵培养基进行优化。方法以长双歧杆菌（Bifidobacteriumlongum）为发酵菌株，以MRS培养基为基础培养基，以发酵液活菌数为指标，通过单因素添加实验考察发酵培养基的碳源和氮源的种类，并验证优化后培养基的效果。结果优化后培养基的最适碳源为葡萄糖，最适氮源为酪蛋白胨、牛肉蛋白胨、水解乳蛋白，发酵液活菌数达到2．09×10^9CFU／mL，比原MRS培养基（1．22×10^9CFU／mL）提高了71．30％。结论优化后培养基优于原MRS基础培养基，可应用于长双歧杆菌的液态发酵。

Optimizing fermentation medium of Bifidobacterium longum

Objective To optimize liquid fermentation medium of Bifidobacterium longum. Methods MRS was used as the basic medium; viable count in fermentation broth was used as the evaluation index. Single factor test was performed to investigate the carbon and nitrogen sources and verify the optimized medium. Results The best carbon source of optimized culture medium was glucose, and the best nitrogen sources were casein peptone, beef peptone and lactalbumin hydrolysate. The viable bacterial count reached 2.09 ×109 CFU/mL, increased by 71.3% compared to original MRS （ 1.22 × 109 CFU/mL）. Conclusion The optimized medium is superior to bas- al medium, and applicable to the Bifidobacterium longum.