Abstract:
:The continuous separation of proteins was performed in a countercurrent gradient chromatography (CGC) system. A magnetically stabilized fluidized bed (MSFB) was used to establish true countercurrent contact of a solid resin with a liquid buffer. STable pH gradients were formed in the system in less than 10 min and remained stable throughout the course of the separation experiment (>2 h). The shape of the pH gradient, which ultimately controls the resolution and purity of the separation, can be controlled by making simple adjustments in the interstitial velocities of the liquid and solid phases. We have performed the separation of myoglobin and human serum albumin (HSA) using this device and achieved concentration factors of 1.75 for myoglobin and 1.2 for HSA. A mathematical model that has no adjustable parameters has been developed that predicts the focusing behaviour and capabilities of the CGC system. Using the model, we have estimated the optimum phase velocities, particle diameters, and equilibrium parameters necessary for achieving high purity and high concentrations. (c) 1995 John Wiley & Sons, Inc.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Evans LL,Burns MAdoi
10.1002/bit.260480508subject
Has Abstractpub_date
1995-12-05 00:00:00pages
461-75issue
5eissn
0006-3592issn
1097-0290journal_volume
48pub_type
杂志文章abstract::Expression of the lactose (lac) operon in the Escherichia coli chromosome has been studied in mixed-sugar chemostat cultures under steady-state and transient conditions. A unified model has been formulated which involves regulation of active inducer (lactose) transport, promoter-operator regulated expression of the la...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260290812
更新日期:1987-06-01 00:00:00
abstract::In this study, white rot fungus, Polyporus brumalis, was applied to degrade dibutyl phthalate (DBP), a major environmental pollutant. The degradation potential and resulting products were evaluated with HPLC and GC/MS. As DBP concentration increased to 250, 750, and 1,250 microM, the mycelial growth of P. brumalis was...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21333
更新日期:2007-08-15 00:00:00
abstract::We performed a macrokinetic and quantitative microbial investigation of a continuously operating bench-scale biofilter treating styrene-polluted gases. The device was filled with a mixture of peat and glass beads as packing medium and inoculated with the styrene-oxidizing strain, Rhodococcus rhodochrous AL NCIMB 13259...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10640
更新日期:2003-07-05 00:00:00
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
doi:10.1002/bit.260371114
更新日期:1991-05-01 00:00:00
abstract::This study investigates the scaling of photobioreactor productivity based on the growth of Nannochloropsis salina incorporating the effects of direct and diffuse light. The scaling and optimization of photobioreactor geometry was analyzed by determining the growth response of a small-scale system designed to represent...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.23324
更新日期:2012-02-01 00:00:00
abstract::Enzymatic hydrolysis of arabinoxylan is an important prerequisite for the utilization of hemicellulose for ethanol fermentation or for making the low calorie sweetener xylitol by catalytic hydrogenation of the generated xylose. This study focus on cloning and characterization of two industrial relevant beta-xylosidase...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20908
更新日期:2006-08-05 00:00:00
abstract::Propionic acid (PA) and its salts are widely used in the food, pharmaceutical, and chemical industries. Microbial production of PA by propionibacteria is a typical product-inhibited process, and acid resistance is crucial in the improvement of PA titers and productivity. We previously identified two key acid resistanc...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25902
更新日期:2016-06-01 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21225
更新日期:2007-05-01 00:00:00
abstract::Morphology has a crucial effect on productivity and the supply of substrate for cultures of filamentous fungi. However, cultivation parameters leading to the desired morphology are often chosen empirically as the mechanisms governing the processes involved are usually unknown. For coagulating microorganisms like Asper...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20130
更新日期:2004-07-20 00:00:00
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journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260331107
更新日期:1989-05-01 00:00:00
abstract::This paper presents a new formulation for the analysis of growth kinetics on multiple nutrients. The baseline for the theory is the concept that a noninteractive growth process occurs among perfectly substitutable nutrients if the locus of points of the substrate concentrations producing equal growth rate is linear. A...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260440203
更新日期:1994-06-20 00:00:00
abstract::Using solid-phase organic synthesis, we have prepared a 432-member (18 x 8 x 3) sample library based on the AG 490 "tyrphostin" template. By utilizing 432 reactors each equipped with a unique radiofrequency memory ID tag, the 432 products could be obtained as discrete entities (i.e., not as mixtures) via 18 + 8 + 3, o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(199824)61:1<7::aid-bit4>3.
更新日期:1998-01-01 00:00:00
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
doi:10.1002/(SICI)1097-0290(19970520)54:4<333::AID-BIT
更新日期:1997-05-20 00:00:00
abstract::The purpose of this study was to understand bacteria profile modification and its applications in subsurface biological operations such as biobarrier formation, in situ bioremediation, and microbial-enhanced oil recovery. Biomass accumulation and evolution in porous media were investigated both experimentally and theo...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(20000705)69:1<47::aid-bit6
更新日期:2000-07-05 00:00:00
abstract::A mixed culture of sulfate-reducing bacteria containing the species Desulfovibrio desulfuricans was used to study sulfate-reduction stoichiometry and kinetics using ethanol as the carbon source. Growth yield was lower, and kinetics were slower, for ethanol compared to lactate. Ethanol was converted into acetate and no...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:2000-12-05 00:00:00
abstract::Conventional wet chemistry methods to determine biomass composition are labor- and time-intensive and require larger amounts of biomass (300 mg) than is often available. To overcome these limitations and to support a high-throughput pretreatment and hydrolysis (HTPH) screening system, this article reports on the devel...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22937
更新日期:2011-02-01 00:00:00
abstract::The use of microalgae for biofuel production will be beneficial to society if we can produce biofuels at large scales with minimal mechanical energy input in the production process. Understanding micro-algal physiological responses under variable environmental conditions in bioreactors is essential for the optimizatio...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24619
更新日期:2013-01-01 00:00:00
abstract::Cellulase production from lignocellulosic materials was studied in solid-state cultivation by both static and mixed techniques under nonaseptic conditions. The effects of fermentation conditions, such as moisture content, pH, temperature, and aeration, on cellulase production by Trichoderma harzianum using a mixture o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260270917
更新日期:1985-09-01 00:00:00
abstract::Lignin, one of the major components of lignocellulosic biomass, plays an inhibitory role on the enzymatic hydrolysis of cellulose. This work examines the role of lignin in pretreated hardwood, where extents of cellulose hydrolysis decrease, rather than increase with increasing severity of liquid hot water pretreatment...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.25349
更新日期:2015-02-01 00:00:00
abstract::We report the first direct images of the hydration of protein powders. Using an environmental scanning electron microscope (ESEM) we have taken a series of micrographs of a region of the enzyme (subtilisin) power whilst hydrating the sample. In addition, the sample has been viewed during exposure to toluene vapors. Th...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260391114
更新日期:1992-05-01 00:00:00
abstract::Biofilm growth in porous media is difficult to study non-invasively due to the opaqueness and heterogeneity of the systems. Magnetic resonance is utilized to non-invasively study water dynamics within porous media. Displacement-relaxation correlation experiments were performed on fluid flow during biofilm growth in a ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24803
更新日期:2013-05-01 00:00:00
abstract::Pyruvate production by Torulopsis glabrata was used as a model to study the mechanism of product inhibition and the strategy for enhancing pyruvate production. It was found that the concentration of cell growth and pyruvate deceased with the increase of NaCl and sorbitol concentrations. To enhance the osmotic stress r...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21290
更新日期:2007-07-01 00:00:00
abstract::CHO cells express glycoproteins containing both the N-acetylneuraminic acid (Neu5Ac) and minor amounts of the N-glycolylneuraminic acid (Neu5Gc) forms of sialic acid. As Neu5Gc is not expressed in humans and can be recognized as a foreign epitope, there is the potential for immunogenicity issues for glycoprotein thera...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22644
更新日期:2010-04-15 00:00:00
abstract::The activities of pyruvate kinase (PK), pyruvate: formate-lyase (PFL), pyruvate dehydrogenase (PDH), and citrate synthase (CS) involved in the anaerobic glycerol conversion by Klebsiella pneumoniae were studied in continuous culture under conditions of steady states and sustained oscillations. Both the in vitro and in...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:1998-12-05 00:00:00
abstract::Myristic acid esterification has been performed by an immobilized lipase from Mucor Miehei both in n-hexane and in supercritical carbon dioxide (SCCO(2)). The enzyme is stable in SCCO(2) at 15 MPa and 323 K. The reaction rate is influenced by the concentration of water and by the reaction medium composition. A reactio...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260400218
更新日期:1992-06-20 00:00:00
abstract::trans-4-Hydroxy- l-proline (Hyp) is an abundant component of mammalian collagen and functions as a chiral synthon for the syntheses of anti-inflammatory drugs in the pharmaceutical industry. Proline 4-hydroxylase (P4H) can catalyze the conversion of l-proline to Hyp; however, it is still challenging for the fermentati...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26818
更新日期:2019-01-01 00:00:00
abstract::A combined approach based on the use of ATR-FT/IR and steady-state fluorescence spectroscopy allowed to shed light on the effects of the additive methoxypolyethylene glycol (MePEG) on the hydration, conformation and dynamic properties of lipase from Burkholderia cepacia dehydrated to form a film. Spectroscopic data sh...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21888
更新日期:2008-10-01 00:00:00
abstract::Crossflow nanofiltration experiments were performed to investigate the factors influencing the removal of amino acids by a commercially available polymeric thin-film composite membrane. The removals of five monoprotic (Ala, Val, Leu, Gly, and Thr), one diprotic (Asp), and one dibasic (Arg) amino acids in a range of pe...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21395
更新日期:2007-10-01 00:00:00
abstract::Batch fermentations of glucose to ethanol by Z. Mobilis.(ATCC 10988) were examined in several semidefined nutrient media. The measurement of acid produced by the microorganism was used to study its transient fermentation characteristics. Limitation of nitrogen source in the semidefined medium of Rogers and coworkers(2...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260310803
更新日期:1988-05-20 00:00:00
abstract::Clostridium formicoaceticum homofermentatively converts lactate to acetate at 37 degrees C and pH 6.6-9.6. However, this fermentation is strongly inhibited by acetic acid at acidic pH. The specific growth rate of this organism decreased from a maximum at pH 7.6 to zero at pH 6.6. This inhibition effect was found to be...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260340807
更新日期:1989-10-20 00:00:00