鰤鱼诺卡氏菌培养条件及培养基的优化

对鰤鱼诺卡氏菌（Nocardia seriolea）ZJ0503的增菌培养基和生长条件进行优化。研究了温度、盐度、初始pH对鰤鱼诺卡氏菌生长的影响，并通过单因素试验对培养基的碳源、氮源和无机盐成分进行了筛选，采用正交实验法对培养基各主要成分的添加量进行了优化。结果表明，鰤鱼诺卡氏菌最适宜生长条件为温度25 ℃、盐度5、pH 6.5±0.2；经筛选，鰤鱼诺卡氏菌培养基中最佳碳源是葡萄糖，最佳氮源是酵母粉，促生长作用最强的2种无机盐是磷酸氢二钾（K2HPO4）和氯化钙（CaCl2）；确立了培养基优化配方为葡萄糖20 g·L-1，酵母粉15 g·L-1，K2HPO4 0.75 g·L-1，CaCl 20.2 g·L-1（单独灭菌），氯化钠（NaCl2）5 g·L-1，pH 6.5±0.2。

Optimal culture conditions and medium of Nocardia seriolea

We carried out the study to optimize the enrichment medium and culture conditions of Nocardia seriolea （ZJ0503）. We studied the effects of temperature, salinity and initial pH on the growth of N.seriolea, investigated the carbon source, nitrogen source and inorganic ions of N.seriolea with single-factor experiment, and optimized different ingredients of medium with orthogonal experiment. The results indicate that the optimal growing condition of N.seriolea is temperature 25 ℃, salinity 5 and pH 6.5±0.2, the optimum carbon source is glucose, and nitrogen source yeast extract; that K2HPO4 and CaCl 2promote the growth of N.seriolea greatly. In addition, the optimum ingredients of medium are as follows： glucose 20 g？L-1, yeast extract 15 g？L-1, K2HPO4 0.75 g？L-1, CaCl2 0.2 g？L-1 （sterilized separately）, and NaCl 5 g？L-1, pH 6.5±0.2.