金黄色葡萄球菌生物被膜生长动力学分析

Growth Kinetics of Staphylococcus aureus Biofilm

摘要:

利用优化的Liu动力学方程对金黄色葡萄球菌生物被膜的附着过程进行拟合得出：培养温度、培养基pH值、细菌接种浓度都对金黄色葡萄球菌生物被膜的粘附过程有影响，大约在60 min时，金黄色葡萄球菌生物被膜达到粘附平衡。在温度为35 ℃，pH值为7时，附着的微生物量最大，细菌接种浓度越高，附着的微生物量越大。利用Gompertz模型对生物被膜生长、成熟过程进行拟合得出：金黄色葡萄球菌生物被膜生长曲线呈现典型的S型，具有明显的延滞期、指数期和稳定期；生物被膜生长曲线表现出的S型有别于悬浮菌的生长曲线，其指数期相对较短。金黄色葡萄球菌生物被膜粘附过程、生长和成熟过程的模型矫正拟合度R2（Adj）均在0.97之上。表明Liu动力学方程以及Gompertz模型分别适用于描述外界环境与金黄色葡萄球菌生物被膜附着，生长与成熟的关系。

Abstract:

The optimized Liu kinetic equation was used to fit the adhesion process of Staphylococcus aureus biofilm. The results showed that culture temperature and pH as well as inoculum concentration influenced the adhesion process. The adhesion equilibrium of S. aureus biofilm was reached at approximately 60 min. Maximum microbial attachment was achieved at 35 ℃ and pH 7. Additionally, higher inoculum concentration led to increased microbial attachment. The Gompertz model was used to fit the growth and maturation process of the biofilm. The S. aureus biofilm growth curve showed a typical S type, with apparent lag, logarithmic, and stationary phases. This was different from the growth curve of suspended bacteria, which has a relatively short logarithmic phase. The adjusted coefficient of determination R2 (Adj) for the S. aureus biofilm models for adhesion, growth, and maturity were > 0.97, indicating that the Liu kinetic equation and the Gompertz model were suitable to describe the relationship between the external environment and S. aureus biofilm attachment as well as between growth and maturity, respectively.