Abstract:
:We studied the resolution of racemic glycidol through esterification with butyric acid catalyzed by porcine pancreatic lipase in organic media. A screening of seven solvents (log P values between 0.49 and 3.0, P being the n-octanol-water partition coefficient of the solvent) showed that neither log P nor the logarithm of the molar solubility of water in the solvent provides good correlations between enantioselectivity and the properties of the organic media. Chloroform was one of the best solvents as regards the enantiomeric purity (e. p.) of the ester produced. In this solvent, the optimum temperature for the reaction was determined to be 35 degrees C. The enzyme exhibited maximum activity at a water content of 13 +/- 2% (w/w). The enantiomeric purity obtained was 83 +/- 2% of (S)-glycidyl butyrate and did not depend on the alcohol concentration or the enzyme water content for values of these parameters up to 200 mM and 25% (w/w), respectively. The reaction was found to follow a BiBi mechanism.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Martins JF,Da Ponte MN,Barreiros Sdoi
10.1002/bit.260420409subject
Has Abstractpub_date
1993-08-05 00:00:00pages
465-8issue
4eissn
0006-3592issn
1097-0290journal_volume
42pub_type
杂志文章abstract::We propose that transcript levels for some genes are affected by the bacterial cell division cycle and this may be an important factor to consider when designing synthetic bacterial genomes. To test this hypothesis, transcript levels of 58 genes in Escherichia coli B/r A were determined at five times during the cell d...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22098
更新日期:2009-02-15 00:00:00
abstract::Beta defensins are antimicrobial peptides (AMPs) with a broad spectrum antimicrobial behavior against pathogens while having minimal tendency to incur pathogen resistance. Human β-defensin 28 (hBD28) is a strongly cationic AMP and hence hypothesized to be highly effective in permeabilizing negatively-charged pathogen ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22970
更新日期:2011-03-01 00:00:00
abstract::The quality of cassava starch, an important trait in cassava breeding programs, determines its applications in various industries. For example, development of waxy (having a low level of amylose) cassava is in demand. Amylose is synthesized by granule-bound starch synthase I (GBSSI) in plants, and therefore, down-regu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.23120
更新日期:2011-08-01 00:00:00
abstract::The thermo-responsive polymer poly(N-isopropylacrylamide) has received widespread attention for its in vitro application in the non-invasive, non-destructive release of adherent cells on two dimensional surfaces. In this study, 3D non-woven scaffolds fabricated from poly(propylene) (PP), poly(ethylene terephthalate) (...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.24469
更新日期:2012-08-01 00:00:00
abstract::Fungal morphology in many filamentous fungal fermentations leads to high broth viscosity which limits oxygen mass transfer, and often results in reduced productivity. The objective in this study was to determine if a simple, fed-batch, process strategy-pulsed addition of limiting-carbon source-could be used to reduce ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10548
更新日期:2003-04-05 00:00:00
abstract::The kinetics of precipitation of soya protein has been examined in a tubular flow reactor with the precipitants, ammonium sulfate, ethanol, divalent calcium, and sulfuric acid. The precipitate growth profiles obtained in all cases showed the rapid formation of a precipitate phase and the attainment of a final size wit...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280312
更新日期:1986-03-01 00:00:00
abstract::The encapsulin nanocompartment from Rhodococcus erythropolis N771 (Reencapsulin) was expressed and purified in wild-type and C-terminally His-tagged forms. Negative-stained transmission electron microscopy, field-flow fractionation combined with multi-angle light scattering and dynamic light scattering analyses showed...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25322
更新日期:2015-01-01 00:00:00
abstract::A two-stage deterministic model of the growth of Saccharomyces cerevisiae is presented. The cell cycle of this organism was used to suggest the basic model structure. The model represents the preparatory processes of substrate uptake and conversion separately from replication and division. The regulation of the fracti...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260190209
更新日期:1977-02-01 00:00:00
abstract::A model was developed to evaluate the effects of cells and surfactants on oxygen transfer in surface-aerated bioreactors. The model assumed the presence of serial layers of adsorbed surfactants and microorganisms directly adjacent to the gas-liquid interface due to their surface activities, followed by a stagnant liqu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260401108
更新日期:1992-12-20 00:00:00
abstract::Screening fifteen strains of white-rot fungi for their ability to decolorize combined bleached kraft effluent showed that Coriolus versicolor in liquid culture removed over 60% of the color of the effluent within six days in the presence of sucrose. Treatment of the same effluent with this fungus, immobilized in beads...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260250814
更新日期:1983-08-01 00:00:00
abstract::The bacterial consortium MPD-M, isolated from sediment associated with Colombian mangrove roots, was effective in the treatment of hydrocarbons in water with salinities varying from 0 to 180 g L(-1). Where the salinity of the culture medium surpassed 20 g L(-1), its effectiveness increased when the cells were immobili...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10318
更新日期:2002-07-20 00:00:00
abstract::Lipid productivity and fatty acid composition are important metrics for the production of high quality biodiesel from algae. Our previous results showed that co-culturing the green alga Chlorella minutissima with Escherichia coli under high-substrate mixotrophic conditions enhanced both culture growth and crude lipid ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25609
更新日期:2015-09-01 00:00:00
abstract::The yeast Pachysolen tannophilus was entrapped in calcium alginate beads to ferment D-xylose on a continous basis in the presence of high cell densities. Experimental operating variables included the feed D-xylose concentration, the dilution rate, and the fermentor biomass concentration. Under favorable operating cond...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260241010
更新日期:1982-10-01 00:00:00
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
doi:10.1002/bit.24750
更新日期:2013-03-01 00:00:00
abstract::Biological sulfate reduction was studied in laboratory-scale gas-lift reactors. Synthesis gas (gas mixtures of H(2)/CO/CO(2)) was used as energy and carbon source. The required biomass retention was obtained by aggregation and immobilization on pumice particles. Special attention was paid to the effect of CO addition ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960420)50:2<136::AID-BIT
更新日期:1996-04-20 00:00:00
abstract::A means of rapidly renaturing denatured protein was devised and evaluated. Three liquids were laminarly layered in a centrifuge tube, in which two solutions sandwiched liquid paraffin so as to form a pseudolipid bilayer. Denatured and aggregted protein placed on the upper surface of liquid paraffin was renatured as it...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260430108
更新日期:1994-01-05 00:00:00
abstract::Dehydrogenase activity assay of activated sludge using the redox dye 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyltetrazolium chloride (INT) was investigated. INT-dehydrogenase activity (INT-DHA) was directly proportional to INT dosage and inversely proportional to bio-mass concentration over limited ranges. INT dosages...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280719
更新日期:1986-07-01 00:00:00
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
doi:10.1002/bit.260420207
更新日期:1993-06-20 00:00:00
abstract::An in vitro toxicity testing system that combines perfusion of a membrane-supported tissue model with measurement of trans-epithelial electrical resistance (TER) is described. The system is fully automated and allows for continuous TER measurements during exposure to a test agent. The utility of this system is demonst...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19960605)50:5<568::AID-BIT
更新日期:1996-06-05 00:00:00
abstract::In this article, an autonomous four-compartment model that describes the endogenous respiration in an aerobic biodegradation process is proposed and analyzed theoretically. First, the multi-time scale of the system's behavior, to be taken into account in subsequent analyses, is emphasized. Then, an identifiability and...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19980120)57:2<155::aid-bit
更新日期:1998-01-20 00:00:00
abstract::James (Jay) E. Bailey was a pioneer in biotechnology and biochemical engineering. During his 30 years in academia he made seminal contributions to many fields of chemical engineering science, including catalysis and reaction engineering, bioprocess engineering, mathematical modeling of cellular processes, recombinant ...
journal_title:Biotechnology and bioengineering
pub_type: 传,历史文章,杂志文章
doi:10.1002/bit.10404
更新日期:2002-09-05 00:00:00
abstract::A sucrose utilization pathway was established in Ralstonia eutropha NCIMB11599 and R. eutropha 437-540 by introducing the Mannheimia succiniciproducens MBEL55E sacC gene that encodes β-fructofuranosidase. These engineered strains were examined for the production of poly(3-hydroxybutyrate) [P(3HB)] and poly(3-hydroxybu...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25469
更新日期:2015-03-01 00:00:00
abstract::This reports on the determination of the overall oxygen transfer coefficient in a mechanically agitated vessel using a randomly pulsed dynamic method. This method consists in exciting the system by randomly switching the inlet gas stream with air or nitrogen with an identical volumetric flow rate. A pseudo-random bina...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260370914
更新日期:1991-04-15 00:00:00
abstract::Biofouling is the undesirable adhesion and development of microorganisms and macroorganisms in a water environment. An electrochemical antifouling system based on management of primary adhesion of microorganisms was developed employing titanium electrode for antifouling of seawater cooling pipes and marine infrastruct...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21022
更新日期:2006-10-20 00:00:00
abstract::Highly substituted polychlorinated biphenyls (PCBs) are known to be very resistant to aerobic biodegradation, particularly the initial attack by biphenyl dioxygenase. Functional evolution of the substrate specificity of biphenyl dioxygenase was demonstrated by DNA shuffling and staggered extension process (StEP) of th...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19990605)63:5<544::aid-bit
更新日期:1999-06-05 00:00:00
abstract::The laminate consisted of several polymer layers, aluminium, and one cellulose-based layer containing the active enzymatic system (e.g., glucose oxidase, catalase, glucose, and CaCO3). During the industrial lamination process, the enzyme layer was exposed to three temperature spikes up to 325 degrees C without signifi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10266
更新日期:2002-07-05 00:00:00
abstract::A titration bioassay, designed to accurately determine the activity of acetoclastic methanogens, is described that also allows evaluation of inhibition due to potential toxicants on the active biomass. The instrument is made of a pH-stat connected to an anaerobic batch reactor. Acetate is blended and mixed with anaero...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10088
更新日期:2002-01-05 00:00:00
abstract::In a previous paper, the overall or macrokinetics of the immobilized glucose oxidase--catalase system has been presented. In this paper a detailed analysis of the interaction of diffusion and reaction in this system will be presented. The mathematical treatment includes two consecutive reactions with two-substrate kin...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260211112
更新日期:1979-11-01 00:00:00
abstract::One of the major bottlenecks in the bioconversion of lignocelluosic feedstocks to liquid ethanol is the recalcitrance of residue following pretreatment, specifically softwood derived residues. Peroxide delignification has previously been shown to effectively aid in the removal of condensed lignaceous moieties from sub...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22768
更新日期:2010-08-15 00:00:00
abstract::Working conditions of a biochemical fuel cell formed by an oxygen cathode and a platinum bioanode in a Saccharomyces cerevisiae suspension metabolizing glucose are described. The biocell response in terms of bioanode potential and current drainage under different fermentation conditions is reported. A kinetic equation...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260171011
更新日期:1975-10-01 00:00:00