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 at 30 degree C ranged from 40 min to 5.0 hr. In this respect immobilized enzyme resembled soluble enzyme in dilute solution (0.11 mg/ml), when the half-live was about 3.5 hr. More concentrated enzyme solution (1 mg/ml) had a half-life of 64 hr, and was, therefore, considerably more stable than the untreated immobilized xanthine oxidase preparations. Inclusion of albumen in storage and assay buffer increased the half-life of bound xanthine oxidase. So also did treatment with glutaraldehyde: in the case of xanthine oxidase bound to Enzarcyl-TIO such treatment increased the half-life at 30 degree C from 3 hr to about 100 hr. Immobilized xanthine dehydrogenase was more stable than immobilized xanthine oxidase: the dehydrogenase lost no activity during continuous assay for 5 hr at 30 degree C. The stability of immobilized urate oxidase depended on the quantity of enzyme used and on the time of stirring during immobilization: thus a preparation was made (by stirring urate oxidase (48 mg/g support) with Enzacryl-TIO for 24 hr) which lost no activity during 350 hr at 30 degree C.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Johnson DB,Coughlan MPdoi
10.1002/bit.260200709subject
Has Abstractpub_date
1978-07-01 00:00:00pages
1085-85issue
7eissn
0006-3592issn
1097-0290journal_volume
20pub_type
杂志文章abstract::In analyzing microbial cellulose utilization, it would be useful to independently measure the mass concentration of cells and cellulase enzymes. Such measurements would allow investigation of the allocation of cellular resources between synthesis of cells and cellulase, in vivo cell- and cellulase-specific cellulose h...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10142
更新日期:2002-02-15 00:00:00
abstract::Saccharomyces cerevisiae (yeast) cells were employed as a source of alcohol dehydrogenase in the NAD(+)-to-NADH reaction. The cells were immobilized in calcium alginate monofilament fibers and used in a biological reactor. The alginate could not be heat sterilized since temperatures above 80 degrees C caused the polym...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260360706
更新日期:1990-10-05 00:00:00
abstract::Overexpression of recombinant proteins in Escherichia coli often leads to a severe growth retardation of the host cells. The phage T7 promoter phi10 in a pET vector was utilized to express human superoxide dismutase. Induction with IPTG lead to an increase in protein content and cell size and a termination of cell div...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10353
更新日期:2002-10-05 00:00:00
abstract::The heterogeneous nature of hollow fiber reactors for cell cultivation requires special considerations for proper design and operation. Downstream concentration of high-molecular-weight proteins has been measured in the shell side of ultrafiltration hollow fiber bioreactors. This distribution resulted from shell-side ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260360905
更新日期:1990-11-01 00:00:00
abstract::PHA, a naturally occurring biopolymer produced by a wide range of microorganisms, is known for its applications as bioplastic. In recent years the use of agro-industrial wastewater as substrate for PHA production by bacterial enrichments has attracted considerable research attention. Crude glycerol as generated during...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24991
更新日期:2013-12-01 00:00:00
abstract::Immunotherapy with ex vivo cultured T cells depends on a large supply of biologically active cells. Understanding the effects of culture parameters is essential for improving the proliferation and efficacy of the expanded cells. Low oxygen tension (5% pO(2)) was previously reported to improve T-cell expansion and alte...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20166
更新日期:2004-08-20 00:00:00
abstract::Aggregates of Escherichia coli confined within hollowfiber reactors were either formed in place by culturing cells within the reactors, or were prepared by injecting a cell suspension that had been concentrated by centrifugation. The effective diffusive permeability of an uncharged nonreacting tracer, nitrous oxide, w...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260320111
更新日期:1988-06-20 00:00:00
abstract::Co-Immobilization of dextransucrase (DS) and dextranase (DN) into calcium alginate includes the co-entrapment of soluble DS and adsorbed DN. DS converts sucrose into dextran, which is the substrate for DN, so that isomalto-oligosaccharides (IMOs) are follow-up products of dextran hydrolysis. The boundary conditions fo...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21810
更新日期:2008-07-01 00:00:00
abstract::Two empirical models for the enzymatic hydrolysis of cellulose are used to analyze the same set of experimental data to determine if one model is superior to the other. Both models adequately describe the data. The parameters in both models may be correlated to the hydrolysis conditions of enzyme, substrate, and produ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260260818
更新日期:1984-08-01 00:00:00
abstract::Fluorotelomer alcohols [FTOHs, F(CF(2))(n) CH(2)CH(2)OH, n = 4, 6, and 8] are emerging environmental contaminants. Biotransformation of FTOHs by mixed bacterial cultures has been reported; however, little is known about the microorganisms responsible for the biotransformation. Here we reported biotransformation of FTO...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24561
更新日期:2012-12-01 00:00:00
abstract::The sec-alcohol dehydrogenase activity of whole cells of Rhodococcus ruber DSM 44541 has been employed as an efficient biocatalytic redox system due to the use of acetone and 2-propanol at elevated concentrations for cofactor regeneration in the oxidation and reduction mode, respectively, and external addition of NADH...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10540
更新日期:2003-03-30 00:00:00
abstract::The flotation of Streptomyces pilosus was studied in the absence and presence of adsorbed Pb(II) ions on the cell walls and with and without using sodium dodecylsulfate (SDS) as collector. Adsorption of SDS onto the organism in the absence and presence of Pb(II) ions was also investigated. It was found that in the abs...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260371009
更新日期:1991-04-25 00:00:00
abstract::A spinning cylindrical filter, known as a spinfilter, permits the mammalian cell bioreactor operation at high perfusion rates leading to very high cell densities (10(7) mL(-1)). Filter screens with openings (25 mum) slightly larger than the average cell size have been used to retain single cells in suspension over a l...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260430209
更新日期:1994-01-20 00:00:00
abstract::The suitability of using annually grown, carrot-sized buffalo gourd (Cucurbita foetidissima) roots as a feedstock for alcoholic fermentation was explored. Roots grown in 1982 and 1983 were slurried, dextrinized and saccharified using Takathermtrade mark and Diazymetrade mark (commercial enzymes manufactured by Miles L...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260290406
更新日期:1987-03-01 00:00:00
abstract::Proper design of fermentation facilities and equipment modification can control the risks associated with largescale production and purification of microbially produced cytotoxic agents and oncogenic viruses. The primary biohazard risks to operators and the environment are generation of aerosols and accidental spills....
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260260808
更新日期:1984-08-01 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::Whole cell pyruvate decarboxylase (PDC) from Candida utilis enhanced the enzymatic production of (R)-phenylacetylcarbinol (PAC) in an aqueous/octanol biotransformation compared to the partially purified PDC especially for a lower range of initial activities (0.3-2.5 U/mL). With an initial activity of 1.1 U/mL and at a...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20959
更新日期:2006-08-20 00:00:00
abstract::An aeration tank/sedimentation tank system is considered for large variations of organic loading. In this case, it is important to take into account the variability of the characteristics describing the oxidation of activated sludge as well as its sedimentation. The minimum cost of the treatment system is also evaluat...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260241105
更新日期:1982-11-01 00:00:00
abstract::Stem cell self-renewal versus differentiation fate decisions are difficult to characterize and analyze due to multiple competing rate processes occurring simultaneously among heterogeneous cell subpopulations. To address this challenge, we describe a mathematical model for cell population dynamics that allows flow cyt...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20244
更新日期:2004-11-05 00:00:00
abstract::The production of volatile industrial chemicals utilizing metabolically engineered extreme thermophiles offers the potential for processes with simultaneous fermentation and product separation. An excellent target chemical for such a process is acetone (Tb = 56°C), ideally produced from lignocellulosic biomass. Caldi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27529
更新日期:2020-08-08 00:00:00
abstract::A mutant of Saccharomyces cerevisiae, which forms large, multicellular flocs in liquid culture, rapidly fermented media containing high concentrations of glucose (100-180 g/L) in a continuous nonaerated tower fermentor at 30 degrees C. The fermentor operated continuously for seven months. Batch and tower fermentor dat...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260260717
更新日期:1984-07-01 00:00:00
abstract::Exchange of enzyme-bound H(2)O with T(2)O in aqueous solution followed by freeze drying provided tritiated water bound to chymotrypsin, subtilisin Carlsberg, and horseradish peroxidase. The desorption of T(2)O from these enzymes suspended in various organic solvents showed that all three enzymes lost enzyme-bound wate...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260390405
更新日期:1992-02-20 00:00:00
abstract::Biosorption of elements is a little understood phenomenon exhibited by some types of even nonliving microbial biomass. A common fungus Rhizopus arrhizus has been reported to take up uranium from aqueous solutions to the extent of 180 mg U(6+)/g. The mechanism of uranium sequestering by this type of biomass was studied...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260240211
更新日期:1982-02-01 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 heterotrophic marine alga Crypthecodinium cohnii is known to produce docosahexaenoic acid (DHA), a polyunsaturated fatty acid with food and pharmaceutical applications, during batch cultivation on complex media containing sea salt, yeast extract, and glucose. In the present study, fed-batch cultivation was studied...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10513
更新日期:2003-03-20 00:00:00
abstract::The results from this study demonstrate that neutral resins can selectively concentrate specific indole alkaloids from dilute aqueous mixtures. Adsorption was observed to provide a one to two order of magnitude improvement in concentrating these alkaloids, as compared to an equivalent single-staged extraction. Since t...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260310905
更新日期:1988-06-05 00:00:00
abstract::Fluorescence in situ hybridization (FISH) has been extensively used in the past decades for the detection and localization of microorganisms. However, a mechanistic approach of the whole FISH process is still missing, and the main limiting steps for the hybridization to occur remain unclear. In here, FISH is approache...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.27462
更新日期:2020-10-01 00:00:00
abstract::The purpose of this article is to provide a few concrete examples of the potential to acceptably reduce the scope of validation and qualification testing based on scientific justification for the specific area of microbial fermentation. The key areas explored include: autoclave operational qualification (OQ) testing, ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.1094
更新日期:2001-07-05 00:00:00
abstract::The key to achieving successful, reproducible results following the introduction of beneficial microbes into soil relies on the survival rate of the inoculated bacteria in a heterogeneous soil environment and hence an improved encapsulation method was developed. Owing to the constraints associated with the inoculum fo...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20957
更新日期:2006-09-05 00:00:00
abstract::Two instruments were developed to mechanize the handling of anaerobic microorganisms for microbial mutant isolation. The instruments automatically dispense liquid or agar medium to large and small 96-well platesand petridishes. Protocols were developed for inoculating different microorganisms, and calibration curves o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280905
更新日期:1986-09-01 00:00:00