On-line gas analysis in animal cell cultivation: I. Control of dissolved oxygen and pH.


:To monitor gas reaction rates in animal cell culture at constant dissolved oxygen concentration (DO) and constant pH it was necessary to develop improved control methods. Decoupling of both controllrs was obtained by manipulation of molar fractions of oxygen and carbon dioxide in the gas phase. Two pairs of DO and pH controllers were designed and tested both in simulation and exprimental runs. The first controller pair was developed for headspace aeration only, whereas the second controller pair was designed for bubble aeration using a microsparger and flushing the headspace with helium. pH was controlled by a conventional discrete PID controller in its velocity form. For DO control two linear state space feedback controllers with parameter adaptation were established. In these controllers the oxygen uptake rate (OUR) was considered as a disturbance and was not included in the mathematical model. The feedback gain adaptation was based on the difference between the actual molar fraction of oxygen at time step n and the initial molar fraction. This difference is related to OUR and was used to increase or decrease the state feedback controller gain (k and k(1), respectively) in a slow manner. With these controllers it was possible to get an excellent online estimate of OUR. In the case of bubble aeration a simple gas phase mass balance was sufficient, whereas during the headspace aeration a liquid phase balance was required. It has been shown that determination of OUR using gas balance requires a significantly better controller performance compared to just keeping DO and pH within reasonable limits. (c) 1995 John Wiley & Sons, Inc.


Biotechnol Bioeng


Oeggerli A,Eyer K,Heinzle E




Has Abstract


1995-01-05 00:00:00












  • Two-stage fermentation with bacteriophage lambda as an expression vector in Escherachia coli.

    abstract::The potential of bacteriophage lambda as an expression vector for a large scale production of cloned-gene proteins was evaluated in batch and continuous bioreactors using a temperature-sensitive mutant in the cl gene, which allows a simple manipulation of temperature as a means to control the phage in the lysogenic or...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Park TH,Seo JH,Lim HC

    更新日期:1991-02-20 00:00:00

  • Fabricating PLGA microparticles with high loads of the small molecule antioxidant N-acetylcysteine that rescue oligodendrocyte progenitor cells from oxidative stress.

    abstract::Reactive oxygen species (ROS), encompassing all oxygen radical or non-radical oxidizing agents, play key roles in disease progression. Controlled delivery of antioxidants is therapeutically relevant in such oxidant-stressed environments. Encapsulating small hydrophilic molecules into hydrophobic polymer microparticles...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Murphy NP,Lampe KJ

    更新日期:2018-01-01 00:00:00

  • Modeling brewers' yeast flocculation

    abstract::Flocculation of yeast cells occurs during the fermentation of beer. Partway through the fermentation the cells become flocculent and start to form flocs. If the environmental conditions, such as medium composition and fluid velocities in the tank, are optimal, the flocs will grow in size large enough to settle. After ...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: van Hamersveld EH,van der Lans RG,Caulet PJ,Luyben KC

    更新日期:1998-02-05 00:00:00

  • Promoter methylation and transgene copy numbers predict unstable protein production in recombinant Chinese hamster ovary cell lines.

    abstract::Mammalian cell lines for recombinant protein production need to maintain productivity over extended cultivation times. Long-term stability studies are time and resource intensive, but are widely performed to identify and eliminate unstable candidates during cell line development. Production instability of manufacturin...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Osterlehner A,Simmeth S,Göpfert U

    更新日期:2011-11-01 00:00:00

  • Effect of dissolved oxygen on nitrogen fixation by A. vinelandii. I. Free cell cultures.

    abstract::As part of an investigation into the use of biological nitrogen fixation for fertilizer ammonia production, continuous culture studies of respiration and nitrogen fixation in the aerobic bacteria Azotobacter vinelandii under oxygen-limited conditions were conducted. Respiration and growth rates followed Monod forms wi...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Diluccio RC,Kirwan DJ

    更新日期:1984-01-01 00:00:00

  • Permeability of alginate microcapsules to secretory recombinant gene products.

    abstract::Non-autologous somatic gene therapy is an alternate approach to delivering recombinant gene products through implantation of a "universal" donor cell line engineered to produce a therapeutic gene product. The cells are immunologically isolated by enclosure in immunoprotective microcapsules fabricated from alginate-pol...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Awrey DE,Tse M,Hortelano G,Chang PL

    更新日期:1996-11-20 00:00:00

  • Propane-Induced biodegradation of vapor phase trichoroethylene.

    abstract::Microbial degradation of trichloroethylene (TCE) has been demonstrated under aerobic conditions with propane. The primary objective of this research was to evaluate the feasibility of introducing a vapor phase form of TCE in the presence of propane to batch bioreactors containing a liquid phase suspension of Mycobacte...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Wilcox DW,Autenrieth RL,Bonner JS

    更新日期:1995-05-20 00:00:00

  • Lipase activity in vesicular systems: characterization of candida cylindracea lipase and its activity in polymerizable dialkylammonium surfactant vesicles.

    abstract::Lipase from Candida cylindracea (CCL) was incorporated into polymerizable positively charged dialkylammonium bromide surfactant vesicles. The enzyme was incorporated by the use of the dehydration-rehydration method or by incubation. In the latter case, trapping efficiencies of up to 100% could be obtained. Activities ...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Mosmuller EW,Franssen MC,Engbersen JF

    更新日期:1993-06-20 00:00:00

  • Display of lipase on the cell surface of Escherichia coli using OprF as an anchor and its application to enantioselective resolution in organic solvent.

    abstract::We have developed a new cell surface display system using a major outer membrane protein of Pseudomonas aeruginosa OprF as an anchoring motif. Pseudomonas fluorescens SIK W1 lipase gene was fused to the truncated oprF gene by C-terminal deletion fusion strategy. The truncated OprF-lipase fusion protein was successfull...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Lee SH,Choi JI,Han MJ,Choi JH,Lee SY

    更新日期:2005-04-20 00:00:00

  • Process performance and product quality in an integrated continuous antibody production process.

    abstract::Continuous manufacturing is currently being seriously considered in the biopharmaceutical industry as the possible new paradigm for producing therapeutic proteins, due to production cost and product quality related benefits. In this study, a monoclonal antibody producing CHO cell line was cultured in perfusion mode an...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Karst DJ,Steinebach F,Soos M,Morbidelli M

    更新日期:2017-02-01 00:00:00

  • Effects of scaffold microstructure and low intensity pulsed ultrasound on chondrogenic differentiation of human mesenchymal stem cells.

    abstract::The effects of low intensity pulsed ultrasound (LIPUS) on proliferation and chondrogenic differentiation of human mesenchymal stem cells (hMSCs) seeded on 3D printed poly-(ethylene glycol)-diacrylate (PEG-DA) scaffolds with varying pore geometries (square and hexagonal channels) were investigated. The scaffold with sq...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Aliabouzar M,Lee SJ,Zhou X,Zhang GL,Sarkar K

    更新日期:2018-02-01 00:00:00

  • Effect of pH change on the performance and microbial community of enhanced biological phosphate removal process.

    abstract::An acetate-rich wastewater, containing 170 mg/L of total organic carbon (TOC), 13 mg/L of N, and 15 mg/L of P, was treated using the enhanced biological phosphate removal (EBPR) process operated in a sequencing batch reactor. A slight change of pH of the mixed liquor from 7.0 to 6.5 led to a complete loss of phosphate...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Zhang T,Liu Y,Fang HH

    更新日期:2005-10-20 00:00:00

  • Quantitative and kinetic study of oxidative stress regulons using green fluorescent protein.

    abstract::Potentially damaging reactive oxygen species (ROS) are involved in a number of pathways ranging from signal transduction to apoptosis. Cells have adapted this alteration in redox status into a complex regulatory mechanism. ROS are specifically able to induce the expression of a multitude of genes. We constructed and c...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Lu C,Albano CR,Bentley WE,Rao G

    更新日期:2005-03-05 00:00:00

  • Progression of continuous downstream processing of monoclonal antibodies: Current trends and challenges.

    abstract::Rapid advances in intensifying upstream processes for biologics production have left downstream processing as a bottleneck in the manufacturing scheme. Biomanufacturers are pursuing continuous downstream process development to increase efficiency and flexibility, reduce footprint and cost of goods, and improve product...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章,评审


    authors: Somasundaram B,Pleitt K,Shave E,Baker K,Lua LHL

    更新日期:2018-12-01 00:00:00

  • Polymerization mechanism of polypeptide chain aggregation.

    abstract::The misfolding of polypeptide chains and aggregation into the insoluble inclusion body state is a serious problem for biotechnology and biomedical research. Developing a rational strategy to control aggregation requires understanding the mechanism of polymerization. We investigated the in vitro aggregation of P22 tail...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Speed MA,King J,Wang DI

    更新日期:1997-05-20 00:00:00

  • Optimization of batch processes involving simultaneous enzymatic and microbial reactions.

    abstract::Two general models for batch simultaneous enzymatic and microbial reaction (SEMR) processes are presented, the second derived from and simpler than the first and accounting for enzyme denaturation. Using the second model and parameter values from the literature, simulation was used to examine a range of enzyme additio...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Asenjo JA,Sun WH,Spencer JL

    更新日期:1991-05-01 00:00:00

  • Analysis of a continuous, aerobic, fixed-film bioreactor. I. Steady-state behavior.

    abstract::The analysis of a continuous, aerobic, fixed-film bioreactor is performed by simulating the behavior of penicillin production in a three-phase fluidized bed. Rigorous mathematical models are developed for a fluidized-bed fermentor in which bioparticles are fluidized by the liquid medium and air. The steady-state perfo...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Park Y,Davis ME,Wallis DA

    更新日期:1984-05-01 00:00:00

  • Effect of subunit dissociation, denaturation, aggregation, coagulation, and decomposition on enzyme inactivation kinetics: II. Biphasic and grace period behavior.

    abstract::A model previously developed to characterize enzymatic in activation behavior was used to explain the non-first-order biphasic and grace period phenomena that are often observed with oligomeric enzymes. Luciferase and urease were used as model enzyme such as luciferase, the oligomer initially dissociates reversibly in...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Lencki RW,Arul J,Neufeld RJ

    更新日期:1992-12-20 00:00:00

  • Ethanol production from nonsterilized carob pod extract by free and immobilized Saccharomyces cerevisiae cells using fed-batch culture.

    abstract::The production of ethanol from carob pod extract by free and immobilized Saccharomyces cerevisiae cells in batch and fed-batch culture was investigated. Fed-batch culture proved to be a better fermentation system for the production of ethanol than batch culture. In fed-batch culture, both free and immobilized S. cerev...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Roukas T

    更新日期:1994-02-05 00:00:00

  • Gene delivery to overcome astrocyte inhibition of axonal growth: an in vitro model of the glial scar.

    abstract::After injury to the central nervous system, a glial scar develops that physically and biochemically inhibits axon growth. In the scar, activated astrocytes secrete inhibitory extracellular matrix, of which chondroitin sulfate proteoglycans (CSPGs) are considered the major inhibitory component. An inhibitory interface ...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Tuinstra HM,Ducommun MM,Briley WE,Shea LD

    更新日期:2013-03-01 00:00:00

  • Coupling of concanavalin A to cellulose hollow fibers for use in glucose affinity sensor.

    abstract::This article describes a method for the chemical immobilization of concanavalin A (Con A) on the inside wall of a single hollow cellulose fiber for use in glucose affinity sensor. Periodate oxidation of cellulose fiber followed by a spacer for Con A attachment was deemed to be the most optimal procedure for achieving ...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Srinivasan KR,Mansouri S,Schultz JS

    更新日期:1986-02-01 00:00:00

  • Further improvement of phosphite dehydrogenase thermostability by saturation mutagenesis.

    abstract::Phosphite dehydrogenase represents a new enzymatic system for regenerating reduced nicotinamide cofactors for industrial biocatalysis. We previously engineered a variant of phosphite dehydrogenase with relaxed cofactor specificity and significantly increased activity and stability. Here we performed one round of rando...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: McLachlan MJ,Johannes TW,Zhao H

    更新日期:2008-02-01 00:00:00

  • Precipitation of porcine insulin with carbon dioxide.

    abstract::Recent works have pointed to the use of volatile electrolytes such as carbon dioxide (CO2) dissolved in aqueous solutions as a promising alternative to the precipitating agents conventionally used for protein recovery in the food and pharmaceutical industries. In this work we investigated experimental and theoretical ...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Tashima AK,Ottens M,Van der Wielen LA,Cintra DE,Pauli JR,Filho Pde A,Miranda EA

    更新日期:2009-08-01 00:00:00

  • Cellular reporoduction and extracellular polymer formation by Pseudomonas aeruginosa in continuous culture.

    abstract::The kinetics of cellular reproduction and the rate and extent of synthesis of extracellular polymeric substances (EPS) were investigated for P. aeruginosa growing in glucose-limited chemostats. mu(max) and K(s) estimates of 0.4 h(-1) and 2 mg glucose C/L, respectively, at 25 degrees C were obtained for this bacterium....

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Robinson JA,Trulear MG,Characklis WG

    更新日期:1984-12-01 00:00:00

  • Anaerobic digestion of cellulose fraction of domestic refuse by means of rumen microorganisms.

    abstract::The anaerobic digestion of a cellulose-enriched fraction of domestic refuse by means of rumen microorganisms in an "artificial rumen" digester was studied. Various combinations of solid and liquid retention times and loading rates were applied to establish optimum conditions for the acidogenic phase digestion of the r...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Gijzen HJ,Zwart KB,Teunissen MJ,Vogels GD

    更新日期:1988-09-05 00:00:00

  • Gene transcription acceleration: main cause of hepatitis B surface antigen production improvement by dimethyl sulfoxide in the culture of Chinese hamster ovary cells.

    abstract::The production and specific productivity of hepatitis B surface antigen (HBsAg) in recombinant Chinese hamster ovary (CHO) cells were increased by 81% and threefold, respectively, when supplemented with 1.5% dimethyl sulfoxide (DMSO) in the culture medium. To investigate the mechanism of DMSO effect on HBsAg productio...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Wang W,Yi X,Zhang Y

    更新日期:2007-06-15 00:00:00

  • Prediction of the profiles of the elution bands of proteins in preparative liquid chromatography.

    abstract::A semiequilibrium model of chromatography has been developed to account for the elution profile of high concentration bands. The use of this model requires the prior determination of the equilibrium isotherms of the studied compounds in the chromatographic phase system. The model is applied here to a study of the isoc...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Katti A,Huang JX,Guiochon G

    更新日期:1990-07-01 00:00:00

  • Laboratory-scale production of acetoin plus diacetyl by Enterobacter cloacae ATCC 27613.

    abstract::Conditions for the laboratory-scale production of acetoin plus diacetyl by Enterobacter cloacae ATCC 27613 were studied. Thirty-five g acetoin plus diacetyl/50 g sucrose were obtained when fermentation was carried out in 2.5 liter medium containing 12.5 g peptone and 12.5 g yeast extract, at pH 7.0, in a 5 liter conic...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Gupta KG,Yadav NK,Dhawan S

    更新日期:1978-12-01 00:00:00

  • Kinetics of ethanol inhibition in alcohol fermentation.

    abstract::The inhibitory effect of ethanol on yeast growth and fermentation has been studied for the strain Saccharomyces cerevisiae ATCC No. 4126 under anaerobic batch conditions. The results obtained reveal that there is no striking difference between the response of growth and ethanol fermentation. Two kinetic models are als...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Luong JH

    更新日期:1985-03-01 00:00:00

  • Isolation and expression of a Bacillus cereus gene encoding benzil reductase.

    abstract::Benzil was reduced stereospecifically to (S)-benzoin by Bacillus cereus strain Tim-r01. To isolate the gene responsible for asymmetric reduction, we constructed a library consisting of Escherichia coli clones that harbored plasmids expressing Bacillus cereus genes. The library was screened using the halo formation ass...

    journal_title:Biotechnology and bioengineering

    pub_type: 杂志文章


    authors: Maruyama R,Nishizawa M,Itoi Y,Ito S,Inoue M

    更新日期:2001-12-20 00:00:00