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Oxygen transfer rates in a mammalian cell culture bioreactor equipped with a cell-lift impeller (1990)

Johnson, M. ; André, G. ; Chavarie, C. ; [et al.]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 35 (1990), S. 43-49

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ISSN: 0006-3592

Keywords: Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: Measurements of kLa were carried out in 1. 5- and 5-L New Brunswick Scientific CelliGen® bioreactors. The measured kLa in water were identical for both vessel sizes operated in similar condition. The mass transfer rate increased with temperature, mixing speed, and aeration rate, with this last parameter being the most significant. Surface aeration alone gave kLa values of 0. 4 to 1. 6 h-1. A 25% decrease in kLa was observed above an aeration rate of 1. 6 vvm. This was caused by the particular foam breaker of the CelliGen bioreactor. Measurements of kLa using a mammalian cell culture medium supplemented with 5% fetal calf serum (FCS) have confirmed the negative effect of the foam breaker on kLa The measured value in this medium was 1. 2 h-1 for all aeration rates, more than 60% of which was attributed to surface aeration.

Additional Material: 6 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/bit.260350107

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Production of indole alkaloids by surface immobilized C. roseus cells (1990)

Archambault, J. ; Volesky, B. ; Kurz, W. G. W.

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 35 (1990), S. 660-667

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ISSN: 0006-3592

Keywords: Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: A technique was developed to surface immobilize plant cells and was scaled up in laboratory size bioreactors. This technique was shown not to hinder the biosynthetic potential of Catharanthus roseus immobilized cells and to induce a partial release (300 μg/L) of serpentine into the culture medium contrary to suspension cultured cells. The release pattern seemed to follow the biosynthesis trends of the product. This release mechanism could be stimulated by a factor of 10 within 2 h by increasing the pH of the culture from 5.0 to 5.5.

Additional Material: 5 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/bit.260350703

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Development of a helical-ribbon impeller bioreactor for high-density plant cell suspension culture (1992)

Jolicoeur, M. ; Chavarie, C. ; Carreau, P. J. ; [et al.]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 39 (1992), S. 511-521

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ISSN: 0006-3592

Keywords: plant cell ; Catharanthus roseus ; suspension ; culture ; mixing ; helical ribbon impeller ; bioreactor ; Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: A double helical-ribbon impeller (HRI) bioreactor with a 11-L working volume was developed to grow high-density Catharanthus roseus cell suspensions. The rheological behavior of this suspension was found to be shear-thinning for concentrations higher than 12 to 15 g DW · L-1. A granulated agar suspension of similar rheological properties was used as a model fluid for these suspensions. Mixing studies revealed that surface baffling and bottom profiling of the bioreactor and impeller speeds of 60 to 150 rpm ensured uniform mixing of suspensions. The HRI power requirement was found to increase singnificantly for agar suspensions higher than 13 g DW · L-1, in conjunction with the effective viscosity increase. Oxygen transfer studies showed high apparent surface oxygen transfer coefficients (kLa ∼4 to 45 h-1) from agar suspensions of 30 g DW · L-1 to water and for mixing speeds ranging from 120 to 150 rpm. These high surface kIa values were ascribed to the flow pattern of this bioreactor configuration combined with surface bubble generation and entrainment in the liquid phase caused by the presence of the surface baffles. High-density C. roseus cell suspension cultures were successfully grown in this bioreactor without gas sparging. Up to 70% oxygen enrichment of the head space was required to ensure sufficient oxygen supply to the cultures so that dissolved oxygen concentration would remain above the critical level (≥10% air saturation). The best mixing speed was 120 rpm. These cultures grew at the same rate (∼0.4 d-1) and attained the same high biomass concentrations (∼25 to 27 g DW · L-1, 450 to 500 g filtered wet biomass · L-1, and 92% to 100% settled wet biomass volume) as shake flask cultures. The scale-up potential of this bioreactor configuration is discussed.

Additional Material: 10 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/bit.260390506

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Development of bioreactors for the culture of surface immobilized plant cells (1990)

Archambault, J. ; Volesky, B. ; Kurz, W. G. W.

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 35 (1990), S. 702-711

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ISSN: 0006-3592

Keywords: Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: The scaleup of the technique of plant cell surface immobilization was performed successfully in specifically designed laboratory size bioreactors. The immobilizing matrix was formed into a vertically wound spiral providing for a high immobilizing area-to-volume ratio (0.8-1.2 cm-1). A modified airlift and a mechanically stirred vessel delivered a best bioreactor performance characterized by low biomass frothing and highly efficient plant cell attachment and retention (≥96%). The growth of Catharanthus roseus cells investigated in these bioreactors was found not to be mass transfer limited. It required mild mixing and aeration levels (kLa ∼ 10-15 h-1). The biomass formation pattern of surface immobilized plant cells generally exhibited a linear growth phase followed by a stationary phase characterized by the presence of residual carbohydrates in the medium, contrary to suspension cultures. This behavior was found to depend on the plant cell type and/or line cultured, as well as on the inoculum age. The space restriction and unidirectional growth of the SIPC biofilm combined with the limited availability of essential intracellular nutrients rapidly accumulated from the medium by the stationary phase inoculated plant cells all likely contributed to the culture behavior.

Additional Material: 6 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/bit.260350707

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Culture of insect cells in helical ribbon impeller bioreactor (1991)

Kamen, A. A. ; Tom, R. L. ; Caron, A. W. ; [et al.]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 38 (1991), S. 619-628

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ISSN: 0006-3592

Keywords: bioreactor, helical ribbon impeller ; Sf-9 insect cell culture ; recombinant baculovirus ; respiration rates ; nutrients ; by-products ; Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: An 11-L helical ribbon impeller (HRI) bioreactor was tested for the culture of Spodoptera frugiperda (Sf-9) cells. This impeller and surface baffling ensured homogeneous mixing and high oxygen transfer through surface aeration and surface-induced babble generation. Serum-supplemented and serum-free cultures, using TNMFH and IPL/41 media, respectively, grew a similar specific growth rates(0.031 and 0.028 h-1) to maximum cell densities of 5.5 × 106-6.0 × 106 cells. mL-1 with viability exceeding 98% during exponential growth phase. Growth limitation coincided with glucose and glutamine depletion and production of significant amounts of alanine. The bioreactor was further tested under more stringent conditions by infecting a serum-free medium culture with a recombinant baculovirus. Heterologous protein production of ∼35 μg per 106 cells was comparable to yields obtained in serum-free cultures grown in spinner flasks and petri dishes. Average specific oxygen up-take and carbon dioxide production rates of the serum-free culture prior to infection as measured by on-line mass spectroscopy were 0.20 μmol O2μ·(106 cells)-1 h-1 and 0.22 μmol CO2 · (106 cells)-1h-1 and increased by 30-40% during infection. Therefore, the mixing and oxygenation conditions of this bioreactor were suitable for insect cell culture and recombinant protein production, with limitation being mainly attributed to nutrient depletion and toxic by-product generation.

Additional Material: 7 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/bit.260380607

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