目的  建立白喉杆菌培养基的相关质控标准。方法  分别制备氨氮含量≥1.8 g/L和<1.8 g/L的白喉杆菌培养基用于白喉杆菌大罐培养，采用t检验对培养结果进行统计学分析，并确定最佳培养基配方。按确定的培养基配方制备15批白喉杆菌培养基用于白喉杆菌大罐培养，检测培养收获的白喉毒素絮状单位，并分析培养基氨氮含量与白喉杆菌产毒间的相关关系。配制15批15%~20%的麦芽糖溶液，分别作为补料于白喉杆菌培养过程中加入大罐，检测培养收获的白喉毒素絮状单位，并分析麦芽糖溶液浓度与白喉杆菌产毒间的相关关系。结果  采用氨氮含量≥1.8 g/L的培养基培养收获的白喉毒素絮状单位明显高于采用氨氮含量  <1.8 g/L的培养基培养(t＝0.5635，P＜0.05）。在确定氨氮含量范围（1.8~2.0 g/L）内，培养基氨氮含量与收获的白喉毒素絮状单位呈线性正相关（r=0.52）。当麦芽糖溶液浓度为15%~20%时，麦芽糖溶液浓度与收获的白喉毒素絮状单位呈线性负相关（r＝-0.53）。结论  白喉杆菌培养基氨氮含量控制在1.8~2.0 g/L，补料麦芽糖溶液浓度控制在15%~20%时，大罐培养收获的白喉毒素絮状单位可达到规程要求。

Objective  To establish relative quality standards of Corynebacterium diphtheriae culture medium. Methods  Corynebacterium diphtheriae culture media with ≥1.8 g/L and <1.8 g/L ammonia nitrogen were prepared respectively, to use for Corynebacterium diphtheriae culture in large fermtor. The statistical analysis of the culture results were made by t test, and the optimal culture medium was identified. Fifteen batches of Corynebacterium diphtheriae culture media were prepared according to the identified formula and used to large fermentor culture. Quantities of diphtheria toxin harvested by culture were detected, and correlativity between ammonia nitrogen contents in Corynebacterium diphtheriae culture medium and diphtheria toxin produced by Corynebacterium diphtheriae was analysed. Fifteen batches of 15%-20% maltose solutions were made up and fed into large fermentor as supplement during Corynebacterium diphtheriae culture. Quantities of diphtheria toxin harvested by culture were detected, and correlativity between concentrations of maltose solutions and diphtheria toxin produced by Corynebacterium diphtheriae was analysed. Results  Quantities of diphtheria toxin harvested from Corynebacterium diphtheriae culture media with ≥1.8 g/L ammonia nitrogen were significantly higher than those harvested from Corynebacterium diphtheriae culture media with <1.8 g/L ammonia nitrogen(t=0.5635,P<0.05). Positive linear correlation was showed between ammonia nitrogen contents in Corynebacterium diphtheriae culture medium and quantities of diphtheria toxin in ranges of identified ammonia nitrogen contents (1.8-2.0 g/L). When concentrations of maltose solutions ranged from 15% to 20%, negative linear correlation(r=-0.53) was showed between concentrations of maltose solutions and quantities of diphtheria toxin. Conclusion  When ammonia nitrogen contents in Corynebacterium diphtheriae culture medium and concentrations of maltose solutions for feeding into large fermentor are controlled in ranges of 1.8-2.0 g/L and 15%-20% respectively, quantities of diphtheria toxin harvested by large fermentor culture can achieve requirements of the regulation.