Animal and Plant Cell Cultures

Animal or plant cell cultures are used to produce vaccines, monoclonal antibodies, blood components, and other important medicinal products. The involved mechanisms are biological in nature and are therefore not discussed in detail here. 

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Animal and Plant Cell Cultures. Bioprocess engineering incorporating animal cell culture is used primarily for the production of health care products such as viral vaccines or antibodies in traditional fermenters or bioreactors with immobilized cells. Antibodies, for example, are produced in bioreactors with hoUow-fiber immobilized animal cells. Plant cell culture is also an important target of bioprocess engineering. However, only a few processes have been successfully developed. One successful process is the production of the pigment shikonin in Japan. Shikonin is used as a dye for coloring food and has applications as an anti-inflammatory agent. 

In airlift bioreactors the fluid volume of the vessel is divided into two interconnected zones by means of a baffle or draft-tube (Fig. 5). Only one of these zones is sparged with air or other gas. The sparged zone is known as the riser the zone that receives no gas is the downcomer (Fig. 5a-c). The bulk density of the gas-liquid dispersion in the gas-sparged riser tends to be less than the bulk density in the downcomer consequently, the dispersion flows up in the riser zone and downflow occurs in the downcomer. Sometimes the riser and the downcomer are two separate vertical pipes that are interconnected at the top and the bottom to form an external circulation loop (Fig. 5c). External-loop airlift reactors are less common in commercial processes compared to the internal-loop designs (Fig. 5a, b). The internal-loop configuration may be either a concentric draft-tube device or an split-cylinder (Fig. 5a, b). Airlift reactors have been successfully employed in nearly every kind of bioprocess—bacterial and yeast culture, fermentations of mycelial fungi, animal and plant cell culture, immobilized enzyme and cell biocatalysis, culture of microalgae, and wastewater treatment. 

The basic bioreactor configurations discussed above for heterotrophic growth (i.e., stirred tanks, bubble columns and airlift bioreactors, packed and fluidized beds) are generally satisfactory for a great majority of bioprocessing needs. In addition, some basic configurations have been especially adapted to better suite specific applications. For example, stirred vessels for animal and plant cell cultures employ different designs of impeller compared to ones... 

Tissue culture, more frequently used as cell culture, enables animal and plant cells to be cultured in large numbers by techniques comparable to those used in microbiology but, because of the fragile nature of the cells, does require special cultural conditions. The culture media used must supply all the essential factors for growth, such as a wide range of amino acids, nucleotides, enzyme co-factors as well as indeterminate factors that can only be supplied in special products, e.g. foetal bovine serum. The environmental conditions must be carefully controlled, particularly pH, and this is frequently maintained by culturing in a bicarbonate buffer system and a carbon dioxide saturated atmosphere. 

Tam WHJ, Constabel F, Kurz WGW (1980) Codeine from cell suspension cultures of Papaver somniferum. Phytochemistry 18 486-487 White PR (1963) The cultivation of animal and plant cells. Ronald Press, New York Yamamoto H, Ishida M, Tomimoro T (1981) Studies on the fundamental cultures of Coptis japonica voi. faponica. Shoyakugaku Zasshi 35 1-8 Zenk MH, Deus B (1982) Natural product synthesis by plant ceU cultures. Plant tissue culture 1982. Proc 5th Int Congr Plant Tissue CeU Culture, pp 391-392 Zito SW, Staba EJ (1982) Thebaine from root cultures of Papaver bracteatum. Planta Med 45 53-54... 

Although plant cell culture is not as cost effective as plant cultivation in the open field, it will become an economical process if higher protein yields can be achieved [58]. The cultivation medium of plants is chemically defined, consisting of a carbon source, minerals, vitamins and phytohormones [69]. Furthermore, it is protein-free and relatively inexpensive. In contrast, animal cells often require complex supplements such as fetal calf serum and/or expensive growth factors, although serum-free cultivation is possible in case of Chinese hamster ovary (CHO) cells [70]. 

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