Kinetics and Fermenter Design

Understanding the growth kinetics of microbial, animal, or plant cells is important for the design and operation of fermentation systems employing them. Cell kinetics deals with the rate of cell growth and how it is affected by various chemical and physical conditions. 

Therefore, we must make assumptions to be able to arrive at simple models which are useful for fermenter design and performance predictions. Various models can be developed based on the assumptions concerning cell components and population as shown in Table 6.1 (Tsuchiya et al., 1966). The simplest model is the unstructured, distributed model which is based on the following two assumptions  

Cells can be represented by a single component, such as cell mass, cell number, or the concentration of protein, DNA, or RNA. This is true for balanced growth, since a doubling of cell mass for balanced growth is accompanied by a doubling of all other measurable properties of the cell population. 

Distributed Cells are represented by a single component, which is uniformly distributed throughout the culture Multiple cell components, uniformly distributed throughout the culture interact with each others 

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