Standard bioreactor

Another very important advantage of miniaturized bioreactors is that scale-up takes on a different form. The scale-up procedure for standard bioreactors and miniaturized bioreactors is compared in Figure 10.5. The scale-up procedure for standard bioreactors involves a complicated iteration processes. A laboratory bioreactor is designed as a proof-of-concept. Next, an experimental-scale bioreactor is designed to ensure production viability. After a few iterations, a small-scale pilot plant is constracted to test and finalize the production process, equipment placement, and economic viability. Once this step is accomplished, a large-scale... 

The numbering-up method also introduces another potential advantage. The scaled model operates as a continuous bioreactor rather than batch while providing the operator with the same control advantages of the batch operation at the same time. Therefore, the process time is expected to be shorter with miniaturized bioreactors since most standardized bioreactors use a process time that is longer than the kinetic minimum. Safety is also increased tremendously since the process can be stopped at any point in the process flow (Ehrfeld et al., 2000). These controls can be instituted automatically without the need for human supervision. 

We were able to achieve the concentration of 93 gL" using our robust wild type strain Yarrowia lipolytica EH59 in our standard bioreactor facility with sunflower oil as substrate. (Heretsch et al. 2008). The product formation in a typical ICA/ CA-cultivation by Yarrowia lipolytica is shown in Figure 19.5. 

There have been numerous communications on the subject of biodegradation test methods, including aerobic compost (30), anaerobic bioreactor (31), general methodology and future directions (32—34), and a fine review article (24). ASTM (22) and MITI (35) have also set forth standard testing protocols for plastics, as shown in Table 2, whereas OECD test methods (29) are more suited to water-soluble polymers. 

Standard components for a bioreactor comprise the vessel, the agitator and impeller, heat exchangers, seals, and valves. Other components include utilities such as clean-in-place (CIP), and steam-in-place (SIP) systems, auxiliary tanks, pH and foam control, inlet tubes,... 

Dechema Study for research and development Standardization and equipment recommendations for bioreactors and peripheral devices (1990)... 

Fig. 14. Calcium response of Sf-9 insect cells subjected to different values of e in a stirred bioreactor equipped with a 5.1 cm diameter 6-bladed Rushton impeller (closed circles) or in the capillary flow system (open squares). Error bars for stirred bioreactor are standard deviation for each experiment but for the capillary, data are hard to discern [99]...

Many interesting biocatalytic reactions involve organic components that are poorly water-soluble. When using organic-aqueous biphasic bioreactor, availability of poorly water-soluble reactants to cells and enzymes is improved, and product extraction can be coupled to the bioreaction. Many applications in two-phase media can use the existing standard-type bioreactors, such as stirred-tank, fluidized-bed, and column reactors with minor adjustments. 

In this section we shall use the standard notation employed by biochemical engineers and industrial microbiologists in presenting the material. Thus if we denote by Xv the viable cell (cells/L) or biomass (mg/L) concentration, S the limiting substrate concentration (mmol/L) and P the product concentration (immol/L) in the bioreactor, the dynamic component mass balances yield the following ODEs for each mode of operation ... 

It is assumed that both state variables x, and x2 are measured with respect to time and that the standard experimental error (oe) is 0.1 (g/L) for both variables. The independent variables that determine a particular experiment are (i) the inoculation density (initial biomass concentration in the bioreactor), Xq i, with range 1 to 10 g/L, (ii) the dilution factor, D, with range 0.05 to 0.20 h 1 and (iii) the substrate concentration in the feed, cF, with range 5 to 35 g/L. 

Table 12.4 Fed-batch Bioreactor Standard Deviation of Parameter Estimates Versus Time Interval Used for the Grid Point (1. 0.20, 35)...

Bioreactor landfill operations should comply with RCRA landfill facility standards under 40 CFR Part 264. It should be noted that SARA strongly recommends on-site treatment that permanently and significantly reduces the volume, toxicity, or mobility of hazardous substances, and utilizes cost-effective permanent solutions. The legislation prohibits land disposal of hazardous wastes unless U.S. EPA determines otherwise. U.S. EPA guidance for CERCLA responses requires most on-site disposal actions to attain or exceed applicable and relevant standards of all Federal public health and environmental laws unless specific circumstances dictate otherwise. 

Considerable effort is often required to prepare sufficient quantities of key mammalian metabolites of drug candidates for biological activity evaluation or for use as analytical standards. The new regulatory guidance in drug development [5] will certainly lead to more emphasis on key human metabolite characterization. Microbial bioreactors can be used for... 

The M20 metabolite is a major circulating metabolite of dasatinib (SPRY CEL) in humans [77]. A large quantity of M20 was needed to serve as an analytical standard, but was not readily accessible by mammalian bioreactors or chemical synthesis. Microbial biotransformation was used to make the metabolite to support the development of dasatinib [58]. 

Zhang, D., Zhang, H., Aranibar, N. et al. (2006) Structural elucidation of human oxidative metabolites of muraglitazar use of microbial bioreactors in the biosynthesis of metabolite standards. Drug Metabolism and Disposition The Biological Fate of Chemicals, 34, 267-280. 

Using large- and small-volume samples, mixed with synthetically produced samples, excellent values were developed. Samples were analyzed for alanine, glucose, glutamine, and leucine in samples removed from an Sf-9 insect cell culture bioreactor. It was seen that purely synthetic standards led to poor predictions of actual runs. The best results were achieved from mixed — actual and synthetic — samples. 

Figure 16.4 Experimental set-up of an on-line FIA system ( ) bioreactor, (2) glycerol standard solution, (3) water for dilution, (4) buffer solution containing NAD, (5) buffer solution containing ferricyanide, (6-1) switch valve, (6-2 and 6-3) injection valves, (7-1 and 7-2) peristaltic pumps, (8) mixing chamber, (9) degasser, (10) flow sensor containing biosensor, and (11) waste. (Reprinted from Sefcovicova et al/ with permission from Elsevier.)...

For ethanol production a substantial improvement over the packed bed reactor is offered by the gas-solid fluidized bed fermenter which uses a liquid instead of a solid substrate and replaces the packed bed of substrate or micro-organisms with a fluidized bed of yeast pellets (Smith et al, 1997). This system can be viewed as a standard fermentation against which the performance of different bioreactors may be assessed. 

Based on these devices, different biomass estimation experiments were performed based on the culture fluorescence monitoring and feeding strategy studies were developed as well as bioreactor characterizations via mixing time experiments. During the next years smaller fluorescence probes were developed which could be interfaced with bioreactors via standard electrode ports. These open end detector systems measured the fluorescence fight in the backward di-... 

For on-line measurement the BioView sensor is connected directly by a 1.5-m bifurcated liquid light conductor (Lumatec, Germany) to a quartz window in a 25-mm electrode standard port of vessel bioreactor (Fig. 2). Contamination and sterilization problems could be avoided, because there is no contact between sensor and fermentation broth. 

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