Abstract:
:Helical-blade solids mixers have a large potential as bioreactors for solid-state fermentation (SSF). Fundamental knowledge of the flow and mixing behavior is required for robust operation of these mixers. In this study predictions of a discrete particle model were compared to experiments with colored wheat grain particles and positron emission particle tracking (PEPT) measurements. In the discrete particle model individual movements of particles were calculated from interaction forces. It was concluded that the predicted overall flow behavior matched well with the PEPT measurements. Differences between the model predictions and the experiments with wheat grains were found to be due to the assumption that substrate particles were spherical, which was in the model. Model simulations and experiments with spherical green peas confirmed this. The mixing in the helical-blade mixer could be attributed to (1) the transport of particles up and down in the interior of the mixer, and (2) dispersion or micro-mixing of particles in the top region of the mixer. It appeared that the mixing rate scaled linearly with the rotation rate of the blade, although the average particle velocity did not scale proportionally. It may be that the flow behavior changes as a function of the rotation rate (e.g., changing thickness of the top region); further study is required to confirm this. To increase the mixing performance of the mixer, a larger blade or a change in the shape of the mixer (larger top surface/volume ratio) is recommended.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Schutyser MA,Briels WJ,Rinzema A,Boom RMdoi
10.1002/bit.10739subject
Has Abstractpub_date
2003-10-05 00:00:00pages
29-39issue
1eissn
0006-3592issn
1097-0290journal_volume
84pub_type
杂志文章abstract::A two-stage bioreactor scheme was developed for the large-scale production of recombinant proteins using a genetically engineered baculovirus/insect cell system. The first bioreactor was employed for cell growth and the second for cell infection. Silkworm Bm5 cells were infected with a recombinant baculovirus, BmNPV/P...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260420313
更新日期:1993-07-01 00:00:00
abstract::We have used a high-throughput LC/MS/UV/ELSD method to rapidly determine the absolute quantity and purity of 42 organic compounds from seven lead discovery libraries. A general calibration curve generated from a different set of 42 compounds with seven different scaffolds was used in this analysis. We have also studie...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(2000)71:2<162::aid-bit1006>3.0.c
更新日期:2000-01-01 00:00:00
abstract::Model experiments were performed with starved yeast (Saccharomyces cerevisiae) cultures in a batch reactor in order to develop a better understanding of NAD(P)H and flavin culture fluorescence. Fluorescence was monitored during aerobic-anaerobic-aerobic transitions and ethanol and glucose substrate addition experiment...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260340510
更新日期:1989-08-20 00:00:00
abstract::A technique has been developed for characterizing the in vivo behavior of key enzymes from intermediate measurements. The technique is based on the identification of characteristic reaction paths, and it depends on the time scale separation characteristics of the systems. It is shown that useful information can be obt...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260310813
更新日期:1988-05-20 00:00:00
abstract::A process is described in which the baboon endogenous virus (BaEV) is produced under optimum conditions in cell culture, and concentrated by hollow-fiber ultrafiltration technology under conditions of large-scale production. This system has advantages over conventional systems in that the flow rate is increased 2.5-fo...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260220103
更新日期:1980-01-01 00:00:00
abstract::Lyophilized proteins exhibit "pH memory," i.e., their behavior in the solid form corresponds to the pH of the aqueous solution from which they were freeze dried. Herein, we directly tested whether the ionization state is "remembered" by model organic compounds containing various protein functional groups (amino, carbo...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19970205)53:3<345::AID-BIT
更新日期:1997-02-05 00:00:00
abstract::The study was done to evaluate the efficacy of using reuterin produced by Lactobacillus reuteri to sanitize biological tissues. The microorganism tested in the study was Pseudomonas aeruginosa, a common cause of nosocomial biomaterial-related infections. The inhibitory effect of reuterin on P. aeruginosa for an inocul...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10764
更新日期:2003-10-20 00:00:00
abstract::A model was formulated to examine specific experimental data of growth and heterologous product formation with recombinant Saccharomyces cerevisiae while incorporating available literature. The model simulated dry cell weight, glucose, ethanol, dissolved oxygen, human Epidermal Growth Factor (hEGF) production, fractio...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260350405
更新日期:1990-02-20 00:00:00
abstract::Two shock loads of a commercial detergent (I-150 mg chemical oxygen demand (COD)/L, fed for 56 h; II-300 mg COD/L fed for 222 h) were applied in a lab-scale Expanded Granular Sludge Blanket (EGSB) reactor, fed with 1,500 mg COD/L of ethanol. The impact of the surfactant was assessed in terms of granular sludge morphol...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21381
更新日期:2007-09-01 00:00:00
abstract::Chinese hamster ovary (CHO) cells are the predominant host cell line for the production of biopharmaceuticals, a growing industry currently worth more than $188 billion USD in global sales. CHO cells undergo programmed cell death (apoptosis) following different stresses encountered in cell culture, such as substrate l...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.27269
更新日期:2020-04-01 00:00:00
abstract::Steam explosion after sulphur dioxide impregnation of wood chips is an effective method for improving the enzymatic digestibility of cellulose in the softwood Pinus radiata. Digestibility of pretreated fiber was progressively increased by altering the conditions of steam explosion. With increasing digestibility, there...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260310509
更新日期:1988-04-05 00:00:00
abstract::Bacterial magnetic particles (BMPs) were used for the identification of cyanobacterial DNA. Genus-specific oligonucleotide probes for the detection of Anabaena spp., Microcystis spp., Nostoc spp., Oscillatoria spp., and Synechococcus spp. were designed from the variable region of the cyanobacterial 16S rDNA of 148 str...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.1073
更新日期:2001-06-05 00:00:00
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
doi:10.1002/bit.21546
更新日期:2008-02-01 00:00:00
abstract::Cell-division-cycle, temperature-sensitive mutants of Saccharomyces cerevisiae were investigated as a means of altering the morphological characteristics and subsequent physical properties of single-cell protein (SCP). Strain 4471, harboring mutation cdc 4, formed a visible complex mass at the nonpermissive temperatur...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260221007
更新日期:1980-10-01 00:00:00
abstract::A balance between proliferation and cell death is critical for achieving desirable high cell densities in mammalian cell culture. In this study, we evaluate a recently discovered anti-apoptotic gene, aven, and examine its effectiveness alone and in combination with a member of the Bcl-2 family, bcl-xL. The commerciall...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10913
更新日期:2004-03-20 00:00:00
abstract::Ion-exchange (IEX) chromatography steps are widely applied in protein purification processes because of their high capacity, selectivity, robust operation, and well-understood principles. Optimization of IEX steps typically involves resin screening and selection of the pH and counterion concentrations of the load, was...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21905
更新日期:2008-08-01 00:00:00
abstract::The stability of immobilized preparations of xanthine oxidase and urate oxidase was studied, and optimized, because of the potential joint use of both enzymes in clinical analysis. Xanthine oxidase was immobilized on cellulose, Sepharose, hornblende, Enzacryl-TIO, and porous glass. Thehalf-lives of these preparations ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260200709
更新日期:1978-07-01 00:00:00
abstract::Effective enzyme-mediated viscosity reduction, disaggregation, or "liquefaction," is required to overcome the rheological challenges resulting from the fibrous, hygroscopic nature of lignocellulosic biomass, particularly at the high solids loadings that will be required for an economically viable process. However, the...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26381
更新日期:2017-11-01 00:00:00
abstract::Understanding the regulatory networks which control specific macrophage phenotypes is essential in identifying novel targets to correct macrophage mediated clinical disorders, often accompanied by inflammatory events. Since mesenchymal stromal cells (MSCs) have been shown to play key roles in regulating immune functio...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25282
更新日期:2014-11-01 00:00:00
abstract::This paper presents an experimental analysis of matrix bead size distribution and voidage variations with axial height in an expanded bed adsorption system. Use of a specially constructed expanded bed with side ports has enabled sampling from within the expanded bed along the vertical axis. Particles removed from with...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20000920)69:6<648::aid-bit9>3.0.
更新日期:2000-09-20 00:00:00
abstract::Start-up phenomena in microbial biokinetic assays are not captured by the most commonly used growth-related equations. In this study we propose a new respirometric experimental design to estimate intrinsic growth parameters that allow us to avoid these limitations without data omission, separate mathematical treatment...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22518
更新日期:2010-01-01 00:00:00
abstract::The scope in improving enzyme productivities from the cellulose fermentation process is examined in laboratory-scale fermentors. The maximum productivity (30 IU/liter hr) is attained in a continuous-culture process with cell recycle using modified medium containing 0.5% cellulose. Optimum dilution rate and recycle rat...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260210213
更新日期:1979-02-01 00:00:00
abstract::The goal of drug delivery is to improve the safety and therapeutic efficacy of drugs. This review focuses on delivery platforms that are either derived from endogenous pathways, long-circulating biomolecules and cells or that piggyback onto long-circulating biomolecules and cells. The first class of such platforms is ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.25307
更新日期:2014-09-01 00:00:00
abstract::To manufacture biotechnology products, mammalian or bacterial cells are engineered for the production of recombinant therapeutic human proteins including monoclonal antibodies. Host cells synthesize an entire repertoire of proteins which are essential for their own function and survival. Biotechnology manufacturing pr...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25647
更新日期:2015-11-01 00:00:00
abstract::A simple approach was developed to determine the half-saturation coefficient for dissolved oxygen (K(DO)) for three bacteria by maintaining a constant oxygen concentration in continuous culture, and employing a dynamic method to obtain the specific growth rate (mu) for each species. Measurement of mu at selected disso...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260250209
更新日期:1983-02-01 00:00:00
abstract::Protein phosphorylation is an important post-translational modification for intracellular signaling molecules, mostly found in serine and threonine residues. Tyrosine phosphorylations are very few events (less than 0.1% to phosphorylated serine/threonine residues), but capable of governing cell fate decisions involved...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25948
更新日期:2016-08-01 00:00:00
abstract::Esters were prepared by acylation of hydroxypropyl cellulose with fatty acid catalyzed by immobilized lipase from Candida antarctica in tert-butanol. The nature of the substrates used, the initial water activity of the system, and the molecular weight of the hydroxypropyl cellulose were investigated. Moreover, Fourier...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20010220)72:4<495::aid-bit1012>3
更新日期:2001-02-20 00:00:00
abstract::We show the design features of a membrane bioreactor based on pulsatile flow across dimpled membranes. Results show an enhanced mass transfer of air of at least five-fold magnitude as compared with flat membranes. An increased working volume form 20 mL to 120 mL reduced the k(L)A at a given Reynolds number because of ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260381016
更新日期:1991-12-05 00:00:00
abstract::Mathematical modeling of animal cell growth and metabolism is essential for the understanding and improvement of the production of biopharmaceuticals. Models can explain the dynamic behavior of cell growth and product formation, support the identification of the most relevant parameters for process design, and signifi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27288
更新日期:2020-05-01 00:00:00
abstract::Purified rat liver phenylalanine hydroxylase [L-phenylalanine:tetrahydropteridine:oxygen oxidoreductase (4-hydroxylating), EC 1.14.16.1] was immobilized with activated thiol-Sepharose 4B via disulfide bond formation, which is expected to immobilize the enzyme in its activated form through the SH modification. This imm...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280422
更新日期:1986-04-01 00:00:00