Abstract:
:The influence of the factors acetic acid, furfural, and p-hydroxybenzoic acid on the ethanol yield (YEtOH) of Saccharomyces cerevisiae, bakers' yeast, S. cerevisiae ATCC 96581, and Candida shehatae NJ 23 was investigated using a 2(3)-full factorial design with 3 centrepoints. The results indicated that acetic acid inhibited the fermentation by C. shehatae NJ 23 markedly more than by bakers' yeast, whereas no significant difference in tolerance towards the compounds was detected between the S. cerevisiae strains. Furfural (2 g L-1) and the lignin derived compound p-hydroxybenzoic acid (2 g L-1) did not affect any of the yeasts at the cell mass concentration used. The results indicated that the linear model was not adequate to describe the experimental data (the p-values of curvatures were 0.048 for NJ 23 and 0.091 for bakers' yeast). Based on the results from the 2(3)-full factorial experiment, an extended experiment was designed based on a central composite design to investigate the influence of the factors on the specific growth rate (mu), biomass yield (Yx), volumetric ethanol productivity (QEtOH), and YEtOH. Bakers' yeast was chosen in the extended experiment due to its better tolerance towards acetic acid, which makes it a more interesting organism for use in industrial fermentations of lignocellulosic hydrolysates. The inoculum size was reduced in the extended experiment to reduce any increase in inhibitor tolerance that might be due to a large cell inoculum. By dividing the experiment in blocks containing fermentations performed with the same inoculum preparation on the same day, much of the anticipated systematic variation between the experiments was separated from the experimental error. The results of the fitted model can be summarised as follows: mu was decreased by furfural (0-3 g L-1). Furfural and acetic acid (0-10 g L-1) also interacted negatively on mu. Furfural concentrations up to 2 g L-1 stimulated Yx in the absence of acetic acid whereas higher concentrations decreased Yx. The two compounds interacted negatively on Yx and YEtOH. Acetic acid concentrations up to 9 g L-1 stimulated QEtOH, whereas furfural (0-3 g L-1) decreased QEtOH. Acetic acid in concentrations up to 10 g L-1 stimulated YEtOH in the absence of furfural, and furfural (0-2 g L-1) slightly increased YEtOH in the absence of acetic acid whereas higher concentrations caused inhibition. Acetic acid and furfural interacted negatively on YEtOH.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Palmqvist E,Grage H,Meinander NQ,Hahn-Hägerdal Bdoi
10.1002/(sici)1097-0290(19990405)63:1<46::aid-bit5subject
Has Abstractpub_date
1999-04-05 00:00:00pages
46-55issue
1eissn
0006-3592issn
1097-0290pii
10.1002/(SICI)1097-0290(19990405)63:1<46::AID-BIT5journal_volume
63pub_type
杂志文章abstract::Cellulase was modified with amphilic copolymers made of alpha-allyl-omega-methoxy polyoxyalkylene (POA) and maleic acid anhydride (MAA) to improve the cellulose hydrolytic reactivity and cellulase separation. Amino groups of the cellulase molecule are covalently coupled with the MAA functional groups of the copolymer....
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260450411
更新日期:1995-02-20 00:00:00
abstract::Novel amphoteric particles are prepared by an interfacial polyaddition reaction of ethylene glycol diglycidyl ether (EGDGE) and L-lysine in a water-in-oil (W/O) miniemulsion system. The zeta-potential of the copolymer particle as a function of pH indicates a sigmoid curve with an isoelectric point at pH 8.7 due to the...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20711
更新日期:2006-02-05 00:00:00
abstract::In recent years there has been a considerable interest in developing membrane chromatography systems that function as a short, wide chromatographic column in which the adsorptive packing consists of one or more microporous membranes. This study reports the use of new adsorber membranes prepared by the incorporation of...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10807
更新日期:2003-12-05 00:00:00
abstract::The enantiocatalytic performance of immobilized lipase in an emulsion membrane reactor using stable emulsion prepared by membrane emulsification technology was studied. The production of optical pure (S)-naproxen from racemic naproxen methyl ester was used as a model reaction system. The O/W emulsion, containing the s...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10826
更新日期:2003-12-20 00:00:00
abstract::Current techniques for characterizing biofilm physiology lack the signal filtering capability required for quantifying signals associated with real time biologically active transport. Though a great deal was learned from previous investigations, no results have been reported on the characterization of in vivo, real ti...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22128
更新日期:2009-02-15 00:00:00
abstract::Based on batch cultivation data for the production of L-glutamic acid from glucose, a comparative evaluation was made for repeated batch cultivations using one and more fermentors. The problem was formulated as maximizing the productivity of metabolic product with the specified conversion with respect to the cell age ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260270524
更新日期:1985-05-01 00:00:00
abstract::Air emissions from the pulp and paper industry frequently contain reduced sulfur compounds (RSC), such as dimethyl sulfide (DMS) mixed with volatile organic compounds (VOC) (e.g., methanol, MeOH) and it is desirable to treat either one or both of these groups of compounds. The objective of this study was to assess the...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21033
更新日期:2006-11-05 00:00:00
abstract::Hydrophobins are small highly surface-active fungal proteins with potential as biosurfactants in a wide array of applications. However, practical implementation of hydrophobins at large scale has been hindered by low recombinant yields. In this study, the effects of increasing hydrophobin gene copy number and overexpr...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26982
更新日期:2019-08-01 00:00:00
abstract::The reporter bacterium, Pseudomonas fluorescens HK44 (HK44), was characterized in an immobilized state to investigate utility for deployment as a remote sensor in the subsurface. A packed-bed reactor with alginate-immobilized HK44 simulated hydrodynamic conditions such as might be found in a subsurface environment. Th...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19970605)54:5<491::AID-BIT
更新日期:1997-06-05 00:00:00
abstract::Cellulosomes are large plant cell wall degrading complexes secreted by some anaerobic bacteria. They are typically composed of a major scaffolding protein containing multiple receptors called cohesins, which tightly anchor a small complementary module termed dockerin harbored by the cellulosomal enzymes. In the presen...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27242
更新日期:2020-03-01 00:00:00
abstract::Clostridium difficile has emerged as a major cause of infectious diarrhea in hospitalized patients, with increasing mortality rate and annual healthcare costs exceeding $3 billion. Since C. difficile infections are associated with the use of antibiotics, there is an urgent need to develop treatments that can inactivat...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26029
更新日期:2016-12-01 00:00:00
abstract::The unicellular green alga Haematococcus pluvialis has been exploited as a cell factory to produce the high-value antioxidant astaxanthin for over two decades, due to its superior ability to synthesize astaxanthin under adverse culture conditions. However, slow vegetative growth under favorable culture conditions and ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25976
更新日期:2016-10-01 00:00:00
abstract::A model for radial flow mammalian cell culture has been developed. Two situations, one with permeable hollow fibers and the other with a porous matrix in the annulus, were considered. The hollow fibers were modeled as continuously distributed sinks. Numerical solutions are presented for the complete model as well as l...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260290602
更新日期:1987-04-01 00:00:00
abstract::Equilibrium isotherms for adsorption of bovine serum albumin (BSA) on a new adsorbent, a strongly basic crosslinked chitosan (Chitopearl 2503), which is hard and is not compressed by pressure in a column, have been presented and compared with diethylaminoethyl (DEAE) Sepharose Fast Flow (hard gel). In Chitopearl 2503,...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260431112
更新日期:1994-05-01 00:00:00
abstract::In eukaryotes, secretory proteins are folded and assembled in the endoplasmic reticulum (ER). Many heterologous proteins are retained in the ER due to suboptimal folding conditions. We previously reported that heterologous secretion of Pyrococcus furiosus beta-glucosidase in Saccharomyces cerevisiae resulted in the ac...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10853
更新日期:2004-02-05 00:00:00
abstract::A 3D printed ultrafiltration/diafiltration (UF/DF) module is presented allowing the continuous, simultaneous concentration of retained (bio-)molecules and reduction or exchange of the salt buffer. Differing from the single-pass UF concepts known from the literature, DF operation does not require the application of sev...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27233
更新日期:2020-03-01 00:00:00
abstract::The redox control bioreactor (RCB) is a new hollow fiber membrane bioreactor (HFMBR) design in which oxygen and hydrogen gases are provided simultaneously through separate arrays of juxtaposed hollow fiber (HF) membranes. This study applied the RCB for completely autotrophic conversion of ammonia to N(2) through nitri...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21617
更新日期:2008-03-01 00:00:00
abstract::The implementation of control algorithms to batch bioreactors is often complicated by variations in process dynamics that occur during the course of fermentation. Such a wide operating range often renders the performance of fixed gain proportional-integral-differential (PID) controllers unsatisfactory. In this work, d...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260320415
更新日期:1988-08-05 00:00:00
abstract::A new type of liquid emulsion membrane containing reversed micelles for protein extraction is introduced. A three-step extraction mechanism is proposed including solubilization, transportation, and release of the protein. The surfactants Span80 and sodium di(2-ethylhexyl)sulfosuccinate (AOT) are used to stabilize the ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19970205)53:3<267::AID-BIT
更新日期:1997-02-05 00:00:00
abstract::Spinner-flask bioreactors have been used for the production of articular cartilage in vitro. The dynamic environment within bioreactors is known to significantly affect the growth and development of the tissue. The present research focuses on the experimental and numerical characterization of the flow field within a s...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10788
更新日期:2004-01-05 00:00:00
abstract::A general framework for a genetically structured model is presented. The framework allows description of the interactions in a system of regulatory and structural genes. The model assumes equilibrium kinetics for the binding of regulatory proteins to the promoter regions of the genes and includes the possible activati...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(1999)66:3<164::aid-bit4>3.
更新日期:1999-01-01 00:00:00
abstract::Dihydrofolate reductase (DHFR) system is used to amplify the product gene to multiple copies in Chinese Hamster Ovary (CHO) cells for generating cell lines which produce the recombinant protein at high levels. The physiological changes accompanying the transformation of the non-protein secreting host cells to a high p...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25117
更新日期:2014-03-01 00:00:00
abstract::Numerous studies on poly γ-d-glutamicacid (γ-PGA) production have investigated terrestrial renewable sources for reducing production costs, but there are no studies using waste marine resources so far. We aimed to develop a cost-effective production method of γ-d-PGA by Bacillus sp. SJ-10 using green macroalgae (Ulva ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26966
更新日期:2019-07-01 00:00:00
abstract::A key challenge for bioprocess engineering is the identification of the optimum process conditions for the production of biochemical and biopharmaceutical compounds using prokaryotic as well as eukaryotic cell factories. Shake flasks and bench-scale bioreactor systems are still the golden standard in the early stage o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.27338
更新日期:2020-07-01 00:00:00
abstract::A proteinase isolated from Thermus RT41a was immobilized to controlled pore glass beads and was used in the free and immobilized forms for peptide synthesis. The observed maximum yield was the same in both cases. a number of dipeptides were produced from amino acid esters and amides. The best acyl components, from tho...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260440311
更新日期:1994-07-01 00:00:00
abstract::The bioartificial pancreas encapsulating pancreatic islets in immunoprotective hydrogel is a promising therapy for Type 1 diabetes. As pancreatic islets are highly metabolically active and exquisitely sensitive to hypoxia, maintaining O2 supply after transplantation remains a major challenge. In this study, we address...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.26913
更新日期:2019-05-01 00:00:00
abstract::The mixed-culture anaerobic conversion of lactose to organic acids in a bench-scale continuous-flow stirredtank fermentor is considered. The major acidogenic end-product distribution with respect to the dilution rate are presented. A Monod chemostat model is employed to describe a microbial growth, and the influence o...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260330516
更新日期:1989-01-25 00:00:00
abstract::The use of a temperature switch to control the growth and productivity of temperature-sensitive (ts) mutants was investigated to extend the productive life span of recombinant Chinese hamster ovary (CHO) cells in batch culture. Bromodeoxyuridine was used at 39 degrees C to select mutagenized CHO-K1 cells, which result...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260420903
更新日期:1993-11-05 00:00:00
abstract::Embryonic stem cells (ESCs) are an important source of cardiomyocytes for regenerating injured myocardium. The successful use of ESC-derived cardiomyocytes in cardiac tissue engineering requires an understanding of the important scaffold properties and culture conditions to promote cell attachment, differentiation, or...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.23353
更新日期:2012-03-01 00:00:00
abstract::CTLA4 is a membrane receptor on cytotoxic T cells whose interaction with the B7 counterreceptor on B cells is important in alloantigen responses. Soluble recombinant human and murine CTLA4 were produced using either Chinese hamster ovary or NS-0 cell lines. Expression vectors were constructed containing the gene codin...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260460502
更新日期:1995-06-05 00:00:00