枯草芽孢杆菌芽孢形成培养条件优化

食品科学论文编号:SP062  论文字数:9856,页数:21

 目  录
中文摘要 I
英文摘要 II
目录 III
1. 绪论 1
 1.1  研究目的 1
 1.2研究概况 1 
2. 实验部分 2
 2.1实验材料、仪器与方法  2
3. 结果与讨论 4
 3.1培养基成分优化    4
 3.2培养条件的优化 8
 3.3 枯草芽孢杆菌生长曲线的研究 12
4．总结与展望 14
 4.1 总结 14
 4.2 展望 14
致谢 15
参考文献 16

摘 要：如果无菌灌装设备灭菌效果差，饮料在无菌灌装过程中，可能会有微生物的滋生，影响产品的品质。因此无菌灌装设备在出厂前，一般需要无菌验证。枯草芽孢杆菌是一种不易被杀死的细菌，常用作测试菌。本论文对枯草芽孢杆菌芽孢形成的培养基成分和培养条件进行优化，为之后无菌灌装的安全性评价做了前期准备。此次试验通过单因素试验，优化出ATCC9372菌株最适宜的发酵培养基组成和培养条件。结果表明枯草芽孢杆菌的最佳培养基配方为：淀粉5g/L,牛肉膏5g/L ,NaCl 3g/L,K2HPO4 3g/L,MnSO4.H2O 2.4mmol。并将培养基pH调至7.0，在250mL三角瓶分装培养基25mL，在37℃下以150r/min 速度摇瓶培养24h。在此培养条件下，枯草芽孢杆菌ATCC9372菌株的活菌数、芽孢数和芽孢率均能达到最高。本实验还通过采用平板计数法和浊度法研究了枯草芽孢杆菌ATCC9372菌株的生长曲线，结果表明其最佳接种龄为6小时。

关键词：枯草芽孢杆菌；芽孢形成；培养基；培养条件
Abstract: Sterilization of aseptic filling equipment, if poor, drinks in aseptic filling process, the microbes may be breeding. So aseptic filling equipment in the factory needs to aseptic validation. Bacillus subtilis is a bacteria that can not easily be killed, often used as test bacteria. The thesis optimized medium components of Bacillus subtilis and culture conditions, For the aseptic filling of the safety eva luation done for it. Through single factor test, optimize the most suitable medium composition and culture conditions. The results showed that Bacillus subtilis optimum medium: starch 5g/L, beef extract 5g/L, NaCl 3g/L, K2HPO4 3g/L, MnSO4.H2O 2.4mmol. And medium pH adjusted to 7.0, in 250mL flask with 10% of the medium ,at 37 ℃ , shaking speed is 150r/min. Under these conditions, viable count, spore count and spore rate to the highest. This study used the plate count and turbidity was studied strains of Bacillus subtilis ATCC9372 growth curve, the results show that the optimal vaccination age of 6 hours.

Keywords：Subtilis; Sporulation; Medium;Culture conditions