Stochastic models to study the impact of mixing on a fed-batch culture of Saccharomyces cerevisiae
Stochastic models to study the impact of mixing on a fed-batch culture of Saccharomyces cerevisiae
复制标题
DOI：
10.1021/bp050255m
复制
发表时间：
2006-01-01
影响因子：
2.9
通讯作者：
Thonart, P
中科院分区：
文献类型：
--
作者：
Delvigne, F;Lejeune, A;Thonart, P
搅拌生物反应器中微生物与环境的相互作用机理可以用随机方法模拟。该过程包括两个子模型：一个经典的随机模型的微生物细胞循环和马尔可夫链模型的浓度梯度演算。优点在于每个子模型的核心，即，转移矩阵（其包含在生物反应器表示中从完全混合的隔室转移到另一个的概率）对于两种情况是相同的。这意味着颗粒循环和流体混合过程可以通过使用相同的建模基础来分析。这一假设已被验证，通过执行惰性示踪剂（NaCl）和染色酵母细胞分散实验，已显示出良好的协议与模拟结果。随机模型已被用来定义的特征浓度曲线的微生物经历的发酵试验过程中进行的规模缩小的反应器。以这种方式获得的浓度曲线可以解释在酿酒酵母分批补料工艺的情况下的规模缩小效应。对模拟结果进行了分析，以解释衬底起伏动力学对S.ae的影响。
The mechanisms of interaction between microorganisms and their environment in a stirred bioreactor can be modeled by a stochastic approach. The procedure comprises two submodels: a classical stochastic model for the microbial cell circulation and a Markov chain model for the concentration gradient calculus. The advantage lies in the fact that the core of each submodel, i.e., the transition matrix (which contains the probabilities to shift from a perfectly mixed compartment to another in the bioreactor representation), is identical for the two cases. That means that both the particle circulation and fluid mixing process can be analyzed by use of the same modeling basis. This assumption has been validated by performing inert tracer (NaCl) and stained yeast cells dispersion experiments that have shown good agreement with simulation results. The stochastic model has been used to define a characteristic concentration profile experienced by the microorganisms during a fermentation test performed in a scale-down reactor. The concentration profiles obtained in this way can explain the scale-down effect in the case of a Saccharomyces cerevisiae fed-batch process. The simulation results are analyzed in order to give some explanations about the effect of the substrate fluctuation dynamics on S.cerevisiae.