Fermenters stirred bioreactors

Zhong, J.J. et al.. Enhancement of anthocyanin production by Perilla frutescens cells in a stirred bioreactor with internal light irradiation, J. Ferment. Bioeng., 75, 299, 1993. 

Figure 20 shows a schematic of a novel membrane-integrated process for citric acid production from glucose syrups by Yarrowia lypolitica ATCC 20346, based on prolonged fed-batch fermentation carried out in a stirred bioreactor coupled to a MF unit equipped with tubular ceramic membranes, and disodium citrate recovery from MF permeates by ED (Moresi, 1995). 

Friedl P, Chang JJ Tatje D (1989) Different oxygen sensitivities of vascular endothelial cells from porcine aorta and from human veins during fermentation in a stirred bioreactor. In Spier RE, Griffiths JB, Stephenne J Crooy PJ (eds) Advances in Animal Cell Biology and Technology for Bioprocesses, pp. 233-237. Butterworth, London. 

The most common cell culture systems developed for pilot- and commercial-scale production of monoclonal antibodies (MAbs) are hollow-fibre and ceramic matrix modules, stirred bioreactors and airlift fermenters. These systems allow cultivation of cells in batch, fed-batch, continuous or perfusion mode. The selection of a culture system and culture mode for the large-scale production of a particular MAb should take into account the growth and antibody-production characteristics of the particular hybridoma line. This module therefore presents an overview of the important characteristics of these systems. Detailed descriptions with accompanying results and a large collection of cited literature are given elsewhere (Seaver, 1987 Mizrahi, 1989 sections 5.1 and 5.9). 

False. The behaviour of stirred bioreactors does not resemble closely pressure-cycle fermenters at any scale. 

Zhang J, Chu D, Huang J, Yu Z, Dai G, Bao J. (2010). Simultaneous saccharification and ethanol fermentation at high corn stover solids loading in a helical stirring bioreactor. 

Fermentation systems obey the same fundamental mass and energy balance relationships as do chemical reaction systems, but special difficulties arise in biological reactor modelling, owing to uncertainties in the kinetic rate expression and the reaction stoichiometry. In what follows, material balance equations are derived for the total mass, the mass of substrate and the cell mass for the case of the stirred tank bioreactor system (Dunn et ah, 2003). 

Several different bioreactor configurations have been described for use in cell culture and fermentation applications. These include stirred tanks,... 

For anaerobic fermentation, the unaerated stirred tank discussed in Section 7.4 is used almost exclusively. One criterion for scaling-up this type of bioreactor is the power input per unit liquid volume of geometrically similar vessels, which should be proportional to for the turbulent range and to for the laminar range, where N is the rotational stirrer speed and L is the representative length of the vessel. 

Several different bioreactor configurations have been described for use in cell culture and fermentation applications. These include stirred tanks, airlift, and hoUow-fiber systems. The majority of bioreactor systems in use for cell culture applications are still of the stirred-tank type. These systems have been used for batch, fed-batch, and perfusion operations. It would not be possible to adequately cover the field of stirred-tank scale-up in the space available here. Instead, this section will touch briefly on the important issues in bioreactor scale-up. For detailed methodologies on stirred-tank bioreactor scale-up, the reader is referred to several review papers on the topic [20,27,28]. 

The production of substances that preserve the food from contamination or from oxidation is another important field of membrane bioreactor. For example, the production of high amounts of propionic acid, commonly used as antifungal substance, was carried out by a continuous stirred-tank reactor associated with ultrafiltration cell recycle and a nanofiltration membrane [51] or the production of gluconic acid by the use of glucose oxidase in a bioreactor using P E S membranes [52]. Lactic acid is widely used as an acidulant, flavor additive, and preservative in the food, pharmaceutical, leather, and textile industries. As an intermediate product in mammalian metabolism, L( +) lactic acid is more important in the food industry than the D(—) isomer. The performance of an improved fermentation system, that is, a membrane cell-recycle bioreactors MCRB was studied [53, 54], the maximum productivity of 31.5 g/Lh was recorded, 10 times greater than the counterpart of the batch-fed fermentation [54]. 

Stirred-tank bioreactors are widely used in the modern biotechnological industry. Most products produced from animal cells on a large scale worldwide are manufactured in this type of bioreactor. In general, these reactors are very similar to fermenters used in industrial submerged culture of microorganisms, and are simple to design, having the shape of a tank and impellers to promote mixture of the contents. 

Historically, the technical term fermenters is used for any reactor design used for microbial or cellular or enzymatic bio conversions and is basically synonymous with a vessel equipped with a stirring and aeration device. (High performance) bioreactors, however, are equipped with as large as possible a number of sensors and connected hard- or software controllers. It is a necessary prerequisite to know the macro- and microenvironmental conditions exactly and to keep them in desired permissive (or even optimal) ranges for the biocatalysts in other words, the bioreaction in a bioreactor is under control [307, 401]. 

Figure 14.3. Bioreactor fermentation of mixed sugars (about 10-12.5% w/v each, glucose and xylose) by L. buchneri strain NRRL B-30929, with lOOrpm stirring and constant pH 5.0. Initial volume is 1000 ml final concentrations are calculated after volume adjustment. Data represent the mean of duplicate fermentation experiments (Liu et al., 2008).

Bioreactors come in many different designs and shapes. The stirred tank reactors are common. They comprise a cylindrical tank, a mechanical stirrer, and a guidance system for the liquid to reduce stress and enhance mixing. Pneumatic reactors use air or oxygen to mix the fermentation broth. The gas is introduced near the bottom of the reactor and induces circulation of the liquid. 

Fig. 9 Bioreactors (A) stirred tank reactor (B) airlift fermenter.

---