肺炎链球菌无动物源冻干保护剂的筛选

Screening of animal-free lyophilized protective agent for Streptococcus pneumoniae

目的制备无动物源保护剂的肺炎链球菌冻干菌种, 并保证菌种活力和菌种保藏时间。方法采用单因素筛选、多因素复配及正交试验, 观察肺炎链球菌在不同温度存放不同时间的稳定性, 从冻干物外观、菌种活力方面进行评价。结果确定保护剂配方为海藻糖20g/L、大豆胨20 g/L、甘露醇60 g/L、甘油6 ml/L。制备的冻干菌种外观良好, 菌种活力可达109 CFU/支, 在2~8 ℃放置2年活菌数无显著下降。结论开发的无动物源成分保护剂适用于冻干菌种制备。

Objective To prepare freeze-dried Streptococcus pneumoniae strains using protective agent without animal-derived components,and ensure the viability and the preservation time of strains.Methods Using single-factor screening,multi-factor compounding with orthogonal experimental design,the stability of Streptococcus pneumoniae stored at different temperatures for various durations was evaluated,and the appearance of the freeze-dried product and the viability of the strains were observed.ResultsThe formula of the protective agents was determined to be trehalose 20 g/L,soy peptone 20 g/L,mannitol 60 g/L,glycerol 6 ml/L.The prepared freeze-dried strains had good appearance.The total bacteria count reached 10^(9) CFU per bottle.The viable counts of the strains kept at 2-8°C for 2 years did not decrease significantly.Conclusion The developed protective agents that do not contain animal-derived components are suitale for freeza-dry preparation.