Bioreactor types

Sub-models depend on the reactor typology and on the biophase state. The broad spectrum of bioreactor types, and associated hydrodynamics, and the different... 

A comparison between insect and mammalian cell culture technology shows various similarities and differences. Due to the fact that insect cell lines typically derive from specific organs or non-differentiated embryonic tissues, the same cell line can proliferate in suspension or in adherent manner (in monolayer). This versatility in growth mode, which contrasts with most mammalian cell lines, increases the choices of bioreactor types and culture strategies for production. Contact inhibition shown by various mammalian cell lines is low or absent for insect cells, and they tend to aggregate in suspension or in adherent cultures. 

The plastic bag is disposable and is provided sterile by the manufacturer. This makes it a very attractive bioreactor type for production purposes, especially if the production scale is not very large. Since it is not sterilized in-house, there is no need for validation of the sterilization procedure. The validation of bag sterilization is the responsibility of its manufacturer. Since it is not reused, there is no need for cleaning and validation of cleaning procedures. Figure 9.6 (see color section) shows a photograph and a schematic representation of a wave bioreactor. 

The manipulation of this bioreactor is generally performed in a laminar-flow cabinet, and is thus an open and risky operation. This is probably a characteristic that differentiates this bioreactor type from the other homogeneous bioreactors, where reliability of all seals and connections can be ensured through the use of direct steam. Also, the large number of connections using flexible tubing makes the operation of this type of bioreactor more complicated than that of other bioreactors of the same class. Currently, the performance and application potential of these bioreactors are under evaluation by the biotechnological community. 

The operation of cultures in perfusion mode is possible for almost all existing bioreactor types. Heterogeneous bioreactors are usually operated in perfusion mode, and homogeneous bioreactors can be if a solid-liquid separation device (cell retention device) is used (see Chapter 11). 

Here, it can be seen that during the last decade research on the design of plant cell bioreactors has witnessed a boom and reached maturity. A future trend in this area is to combine bioreactor type with operational conditions for specific cell lines of characteristic morphology, physiology and metabolism, in order to optimize the processes for secondary metabolite production. 

The choice of the bioreactor type for denitrification of NO to N2 and the regeneration of the chelating agent Fe(II)EDTA2 is another important decision. A properly designed and controlled bioreactor should ensure high biomass concentration, constant temperature and pH, optimal mixing and correct shear conditions. Other important aspects are listed below ... 

Criteria Units Criteria and preferred bioreactor type ... 

Refers to the bioreactor types shown in Figs. 1-5. (From Ref.[ l.)... 

Eigure 2 shows the bioreactor types which are most suitable for MTBE removal. The packed bed reactor (PBR), fluidized bed reactor (EBR) and the membrane bioreactor (MBR) are widely applied. Both the PBR and the EBR are often categorised as fixed film reactors in the literature. 

A continuous bioreactor type plug flow reactor (PFR) with immobilized cell of Saccharomyces cerevisiae in spherical particle was used in the work to take into account the variations of concentrations at the reactor length and inside spherical particle. 

The stirred-tank reactor (STR) is one of the simplest and most widely used bioreactor types. For a preparative resolution of GPE, a mechanieally stirred reactor was operated in batch mode under the above optimal eonditions... 

Flow regime identification is dependent on the geometry of the bioreactor. For example, flow regimes in bnbble columns will be different from those identified in stirred-tank bioreactors. In some cases, the experimental techniques used to identify flow regimes are system independent, while in other cases, the technique was developed for a particular geometry. The specific flow regime definitions in common bioreactor types are described in detail in their respective chapters. 

Figure 8.11 General research papers available in the public domain for different bioreactor types. Acquired 07/01/2013.

Figure 3.3. Classification of bioreactor types on the basis of technical criteria, with examples of known reactor designs. (From A. Moser, 1977a).

Bioreactors. Bioreactors that utilize hving cells are typically called fermenters. There are several different types of bioreactors mechanically stirred or agitated tanks bubble columns (cylindrical tanks that are not stirred but through which gas is bubbled) loop reactors, which have forced circulation packed-bed reactors membrane reactors microreactors and a variety of different types of reactors that are not easily classified (such as gas-Uquid reactors and rotating-disk reactors). Biochemical engineers must choose the best bioreactor type for the desired purpose and outfit it with the right instrumentation and other features. 

Advances in the development of modem chromatography materials and modem equipment have turned scale-up into a less critical issue than it was in the past. Usually, nonchromatographic parameters such as consistency of starting material or limited stability create problems. The scale-up of purification is usually aligned with the scale-up of fermentation. Different reactor types are often used for small and large scale, which may lead to a different composition of the impurities, product concentration, and even molecular structure. Maiorella et al. [90] demonstrated that bioreactor types and culture conditions influence the isoelectric pattern of a monoclonal antibody. This has a big impact on purification because different isoelectric patterns may lead to different solubilities and binding behavior to ion exchangers or other sorbents affected by ionic interactions. 

Hairy roots Bioreactor types Vessel volume (effective volume) (L) Final dry biomass density (g L ) Cultivation time (days) Hyoscyamine (mg g DW) Scopolamine (mg g DW) References... 

Tissue-engineering bioreactors are designed primarily to provide precise control of the cultivation environment. Several characteristics are essential irrespective of the specific bioreactor type or design requirements. These include ... 

TABLE 22.1 Overview of Key Features for the Representative Bioreactor Systems Outlined in This Chapter Bioreactor Type Key Features Example System... 

All of this baseline information is very important for scale-up studies of FA production with immobilized fungus. However, compared with the number of reports generated on different experimental elements (such as carbon source, fxmgal growtir conditions, fxmgal strain, and bioreactor type, among others) associated with FA fermentation production, studies of immobilization-based FA production are yet to receive much attention. 

A brief description of the main bioreactor types follows ... 

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