Packed-Bed Bioreactor

Kasinath A, Novotny C, Svobodova K, Patel KC, Sasek V (2003) Decolorization of synthetic dyes by Irpex lacteus in liquid cultures and packed-bed bioreactor. Enzyme Microb Technol 32 167-173... 

Srikanlayanukul M, Kitwechkun W, Watanabe T, Khanongnuch C (2008) Decolorization of Orange II by immobilized Thermotolerant white rot fungus Coriolus versicolor RC3 in Packed-Bed bioreactor. Biotechnology 7 280-286... 

Moreira MH, Feijoo G, Palma C, Lema JM (1997) Continuous production of manganese peroxidase by Phanerochaete chrysosporium immobilized on polyurethane foam in pulsed packed bed bioreactor. Biotechnol Bioeng 56 130-137... 

Azevedo AM, Vojinovic V, Cabral JMS, Gibson TD, Eonseca LP (2004) Operational stability of immobilised horseradish peroxidase in mini-packed bed bioreactors. J Mol Cat B Enzym 28(2-3) 121-128... 

Scale-up is limited by several factors, such as maximum working velocity in the case of adsorption/ion-exchange upflow fixed beds, and maximum allowable temperature in cases where microorganisms are involved in the process, for example, in the packed bed bioreactors (Michell et al., 1999). 

SVO1/02/03 carrier gas saturation vessel MC01 gas mixing chamber R01 packed bed bioreactor V01 phase separator... 

EC01 feed gas cooler (gas/gas exchanger) R01 packed bed bioreactor EC02 exhaust gas cooler V04 phase separator... 

Consider an idealized simple case of a Michaelis-Menten type bioreaction taking place in a vertical cylindrical packed-bed bioreactor containing immobilized enzyme particles. The effects of mass transfer within and outside the enzyme particles are assumed to be negligible. The reaction rate per dilfcrential packed height (m) and per unit horizontal cross-sectional area of the bed (m ) is given as (cf. Equation 3.28) ... 

Feijoo, G., Dosoretz, C., and Lerna, J.M., Production of lignin peroxidase from Phanerochaete chrysosporium in a packed bed bioreactor with recycling, Biotechnol.-Tech. 1994 vol. 8, no. 5, pp. 363-368. 

While the batch process is the dominant one in current use, researchers and companies have attempted to create continuous bioreactor systems. Lopez et al. immobilized Candida rugosa in polymethacrylamide hydrazide beads and polyurethane foam 3 with the intent to achieve the continuous production of lipase enzymes. Despite flow problems with the polyurethane foam, it showed high lipolytic activity. Biomass buildup was problematic. Feijoo et al. immobilized Phanerochaete chry-sosporium on polyurethane foam in packed bed bioreactors under near-plug flow conditions. Continuous lignin peroxidase production was accomplished, the rate of which was studied as a function of recycle ratio. 

Strandberg G.W., Donaldson, T.L., Farr, L.L. (1989) Degradation of trichloroethylene and trans-1,2-dichloroethylene by a methan-otrophic consortium in a fixed-film, packed-bed bioreactor. Environ. Sci. Technol. 23, 1422-1425. 

Stirred-tank bioreactors Air-lift bioreactors Wave bioreactors Microcarrier-based systems Packed-bed bioreactors Fluidized-bed bioreactors Hollow-fiber bioreactors Bioreactors providing surfaces for attached cell growth (roller bottles, CellCube , Cell Factory)... 

When anchorage-dependent cells are immobilized by microcarriers they can be cultivated in homogeneous bioreactors (Jo et al., 1998). Furthermore, the immobilization on the carriers allows the use of other bioreactors that will be discussed in the following sections, such as fluidized-bed and packed-bed bioreactors. The microcarriers can be separated from the supernatant by sedimentation, facilitating downstream processing or cell retention in perfusion processes. 

Moro AM, Rodrigues MTA, Gouveia MN, Silvestri MLZ, Kalil JE, Raw I (1994), Multi-parametric analyses of hybridoma growth on glass cylinders in a packed-bed bioreactor system with internal aeration. Serum-supplemented and serum-free media comparison for MAb production, J. Immunol. Methods 176 67-77. 

Lewis, V.P and Yang, S.T. 1992. Continuous Propionic Acid Fermentation by Immobilized Propionibacterium Acidipropionici in a Novel Packed-Bed Bioreactor. Biotechnol. Bioeng., 40, 465-474. 

Chong, C. Chang, Y. Deng, J. Xiao, C. Su, Z. A novel scale up method for mammalian cell culture in packed-bed bioreactor. Biotechnol. Lett. 2001, 23, 881-885. 

Wang, G. Zhang, W. Jacklin, C. Freedman, D. Eppstein, L. Kadouri, A. Modified Celligen-packed bed bioreactors for hybridoma cell cultures. Cytotechnology 1992, 9, 41 9. 

Immobilization, dehned as the physical confinement or localization of an enzyme into a specihc micro-environment, has been a very common approach to prepare enzymes for aqueous as well as nonaqueous applications. For nonaqueous enzymol-ogy, immobilization improves storage and thermal stability, facilitates enzyme recovery, and enhances enzyme dispersion. In addition, immobilized enzymes are readily incorporated in packed bed bioreactors, allowing for continuous operation of reactions. Moreover, lyophilized enzyme powders often aggregate and attach to reactor walls, particularly when the water activity is moderately high. The major disadvantage of immobilization is low activity, induced by pore diffusion mass transfer limitations and by alteration of protein stmcture. For enzymes in nonaqueous media, the following broad categories of immobilization exist ... 

The packed-bed reactor is a cylindrical, usually vertical, reaction vessel into which particles containing the catalyst or enzyme are packed. The reaction proceeds while the fluid containing reactants is passed through the packed bed. In the case of a packed-bed bioreactor, a liquid containing the substrate is passed through a bed of particles of immobilized enzyme or cells. 

SBF Submerged biofilter or up-flow flxed/packed bed bioreactor FBR up-flow fluidized bed reactor BTF biotrickling Alter ns Not specified... 

Fig. 2 The effects of recirculation flow rate on cell immobilization efficiency in a packed-bed bioreactor. Cell density=50 g/L...

Fig. 3 (a) Drum bioreactor (7) substrate chamber, (2) loading port, (i) jacket, (4) paddles, (5) central axis, (6) motor, (7) gear box, (S) water inlet, (9) water outlet (70) air inlet, (77) air outlet, (72) product, (b) Packed bed bioreactor (7) water-bath where humidification occurs, (2) air inlet, (3,77) air filter, (4) sparger, (5) water input, (6) water filter, (7) heating coil, (S) basket with perforated bottom, (9) temperature probe for humidified air, (70) medium temperature probe (72) air output, (73) controller and recorder, (77) relative humidity regulator (7), temperature regulator, (A) airflow meter (W) water supply... 

Four basic types of SSF bioreactors have been developed (Figs. 3 and 4). These are (1) drum bioreactor [16], (2) packed bed bioreactor [17,18], (3) tray bioreactor [4, 16], (Ahmed et al. 1987 Hesseltme 1987 Pandey 1991 cited in [19]), and (4) column bioreactor (Raimbault and Germon 1976 cited in [20]). The structure and nature of the solid matrix used, type of microorganism involved, environmental conditions needed for the process, the type of use (research or industrial applications), and type of product should all be considered for the selection of appropriate design of bioreactor [19]. 

Due to the forced aeration, oxygen supply in packed bed bioreactors is usually not a problem, even if quite low aeration rates are used [138]. In contrast, temperature control can be difficult, especially in packed beds above 15 cm diameter and lacking internal heat transfer plates. In such bioreactors, the main heat transfer mechanisms are axial convection and evaporation, and radial temperature gradients are negUgible except close to the bioreactor wall. The dynamics of convective cooHng mean that axial temperature gradients are established and temperatures over 20 °C higher than the inlet air temperature... 

Pressure drops of 1 m of water per meter of bioreactor or higher could quickly put a limit on bioreactor height. These pressure drops need to be carefully considered in the design of the aeration equipment for packed bed bioreactors. If pressure drop is a problem and infi equent mixing can be tolerated, then this mixing can be used to limit the pressure drop [127]. 

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