Secondary metabolites production bioreactor

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. 

In situ extraction for the enhanced production of secondary compounds can be applied in bioreactors. In bioreactor systems low productivity is an important bottleneck, and only a few products are potential candidates for economically feasible production of secondary metabolites using plant cell biotechnology. Several approaches to increase the productivity of secondary metabolites in bioreactors have been made [12]. Among them elicitation and in situ extraction are typical techniques of current interest. Application of these techniques to cell culture systems sometimes increased the productivity to such an extent that they have sometimes been viewed as the gateway to commercial success [10]. However, general rules or suggestions concerning these techniques cannot be made because of the different characteristics of the cell culture systems. 

Gaseous Phase Bioreactor. As shown in Fig. 24, this type of bioreactor is equipped with filters on which the culture is supported and with a shower nozzle for spraying on the medium (Ushiyama et al., 1984 ti l Ushiyama, 1988).1 1 Seed cultures are inoculated on the filters and the medium is supplied to the culture by spraying from a shower nozzle. The drained medium is collected on the bottom of the bioreactor. This type of bioreactor is excellent for plant cell, tissue, and organ cultures because there is no mechanical agitation (e.g., driven impeller, aerator) and, therefore, the growth rate and the secondary metabolite production are enhanced. 

Ahn, J.K. Lee, W.Y. Park, S.Y. (2003). Effect of nitrogen source on the cell growth and production of secondary metabolites in bioreactor cultures of Eleutherococcus senticosus. Korean Journal of Plant Biotechnology, Vol.30, No.3, pp. 301-305, ISSN 1598-... 

The yield of secondary metabolites in a large-scale fermenter typically ranges from 0.1 to lOg/L of broth. Such poor yield leads to cumbersome and expensive processes for both product separation and broth disposal. Within the last decade, several novel bioreactors have been developed for the intensification of fermentation processes. Examples include a centrifugal bioreactor, a rotating packed bed fermenter, and a sonobioreactor. Most of these, however, are yet to be implemented on a production scale because they generally lack practicality and well-defined scale-up criteria. 

Measurement and control systems used in the bioreactor for plants are essentially the same as those for microbial or animal cell cultures, but, in special cases, where the mineral components influence the productivity of secondary metabolites, the kind of salts used for the electrode must be taken into consideration. 

At this point in our discussion of well-stirred continuous-flow bioreactors it is helpful to consider a straightforward extension of our analysis to encompass the possibility of using more than a single feed stream. Illustration 13.5 considers a situation in which a supplementary feed stream is suppUed to the second CSTBR. This illustration lets us address situations in which it is desirable to include additional components (e.g., inducers) in the growth medium to enhance the selectivity of the cascade for the production of desired product species. Induction enhances the production of secondary metabolites becanse of the presence of particular chemical species in the growth medium. 

Cell culture aseptic suspension culture of cells in liquid media in aerated, agitated bioreactors (60,64). The products of primary interest are high-value secondary metabolites. 

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