Abstract:
:The high commercial values of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids have driven a strain-improvement program, aimed at increasing the content of those fatty acids in the microalga Pavlova lutheri (SMBA 60) as parent strain. After a round of mutation using UV-light as mutagenic agent, an isolate strain (tentatively called II#2) was obtained, the EPA and DHA contents of which (in % dry biomass) were 32.8% and 32.9% higher than those of the control, native strain. The final EPA yields, when the cultures were maintained under appropriate conditions, were 17.4 and 23.1 mg. g(-1) dry biomass, for the wild-type and the II#2 strain, respectively, whereas the final DHA yields were 8.0 and 10.6 mg. g(-1) dry biomass, respectively. These results suggest that random mutagenesis can successfully be applied to increase the yield of n-3 fatty acids by microalgae.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Meireles LA,Guedes AC,Malcata FXdoi
10.1002/bit.10451subject
Has Abstractpub_date
2003-01-05 00:00:00pages
50-5issue
1eissn
0006-3592issn
1097-0290journal_volume
81pub_type
杂志文章abstract::Frozen bagged seed inoculum was prepared, thawed and tested for seven cultures. Thawing techniques were developed and other key influences on thawing rate were quantified; seed bag thawing without a water bath rarely required more than 4 to 5 h and was as short as 0.5 to 1 h for lower fill volume bags. Testing include...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10323
更新日期:2002-09-20 00:00:00
abstract::In vivo kinetics of Saccharomyces cerevisiae are studied, in a time window of 150 s, by analyzing the response of O(2) and CO(2) in the fermentor off-gas after perturbation of chemostat cultures by metabolite pulses. Here, a new mathematical method is presented for the estimation of the in vivo oxygen uptake rate (OUR...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.10480
更新日期:2003-02-20 00:00:00
abstract::The objective of this work was to relate macroscopically measurable on-line fermentation parameters such as dissolved oxygen, off-gas oxygen and carbon dioxide, and cell mass, to the controlled production of key intracellular enzymes under carbon limited conditions. Both batch and perturbed batch aerobic fermentations...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260310406
更新日期:1988-03-01 00:00:00
abstract::Microplates with integrated optical oxygen sensors are a new tool to study metabolic rates and enzyme activities. Precise measurements are possible only if oxygen exchange between the sample and the environment is known. In this study we quantify gas exchange in plastic microplates. Dissolved oxygen was detected using...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.20348
更新日期:2005-05-05 00:00:00
abstract::In Part II, the process utility of a thermotolerant methylotrophic bacterium is evaluated with respect to its dynamic response when various substrate or nutrient pulses are imposed on it while growing under steady-state conditions in a chemostat. The pulses investigated were methanol pulses on methanol-, methanol/form...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260360811
更新日期:1990-10-20 00:00:00
abstract::A specially designed model reactor based on a 42-L laboratory fermentor was equipped with six stirrers (Rushton turbines) and five cylindrical disks. In this model reactor, the mixing time, Theta(90), turned out to be 13 times longer compared with the 42-L standard laboratory fermentor fitted with two Rushton turbines...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19990905)64:5<599::aid-bit
更新日期:1999-09-05 00:00:00
abstract::Two metabolic engineering tools, namely gene inactivation and gene overexpression, were employed to examine the effects of two genetic modifications on the fermentation characteristics of Clostridium acetobutylicum. Inactivation of the butyrate kinase gene (buk) was examined using strain PJC4BK, while the combined eff...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:
更新日期:2000-01-05 00:00:00
abstract::Numerous biotechnological production processes are based on the submerse cultivation of filamentous fungi. Process design, however, is often hampered by the complex growth pattern of these organisms. In the morphologic development of coagulating filamentous fungi, like Aspergillus niger, conidial aggregation is the fi...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21569
更新日期:2008-02-01 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::The paper reviews the state-of-the-art in computational modeling of thrombus formation and growth and related phenomena including platelet margination, activation, adhesion, and embolization. Presently, there is a high degree of empiricism in the modeling of thrombus formation. Based on the experimentally observed phy...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章,评审
doi:10.1002/bit.26343
更新日期:2017-10-01 00:00:00
abstract::Anoxic and metabolic stresses in large-scale cell culture during biopharmaceutical production can induce apoptosis. Strategies designed to ameliorate the problem of apoptosis in cell culture have focused on mRNA knockdown of pro-apoptotic proteins and over-expression of anti-apoptotic ones. Apoptosis in cell culture i...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22541
更新日期:2010-02-01 00:00:00
abstract::After separation by microscale non-denaturing two-dimensional gel electrophoresis (2DE) and transferring to a blotting membrane, major proteins are detected by a staining of direct blue 71 in a neutral solution. The carboxylesterase on the membrane hydrolyzes phosphatidylcholine after the spot of carboxylesterase is e...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.21437
更新日期:2007-11-01 00:00:00
abstract::The placement of the reference electrode (RE) in various bioelectrochemical systems is often varied to accommodate different reactor configurations. While the effect of the RE placement is well understood from a strictly electrochemistry perspective, there are impacts on exoelectrogenic biofilms in engineered systems ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.25253
更新日期:2014-10-01 00:00:00
abstract::At the laboratory scale, sudden step increases from 30 to 42 degrees C can be readily accomplished when expressing heterologous proteins in heat-inducible systems. However, for large scale-cultures only slow ramp-type increases in temperature are possible due to heat transfer limitations, where the heating rate decrea...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22084
更新日期:2009-02-01 00:00:00
abstract::Stability of heterologous protein expression during production is critical for regulatory approval of vaccine and therapeutic products. Leishmania GP63, a zinc metalloproteinase that is a potential vaccine candidate, has been expressed on the surface of Chinese hamster ovary (CHO) cells. Flow cytometry was used to fol...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0290(19970320)53:6<594::AID-BIT
更新日期:1997-03-20 00:00:00
abstract::The rate of celluose degradation, limited due to the inhibition by cellobiose, can be increased by the hydrolysis of cellobiose to glucose using immobilized beta-glucosidase. Production of beta-glucosidase in four yeasts was studied and a maximum activity of 1.22 IU/mg cells was obtained in cells of Pichia etchellsii ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260260408
更新日期:1984-04-01 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::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::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::Metabolite accumulation has pleiotropic, toxic, or beneficial effects on cell physiology, but such effects are not well understood at the molecular level. Cells respond and adapt to metabolite stress by mechanisms largely unexplored, especially in the context of multiple and simultaneous stresses. Solventogenic and re...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22628
更新日期:2010-04-15 00:00:00
abstract::The enzyme cellulase, a multienzyme complex made up of several proteins, catalyzes the conversion of cellulose to glucose in an enzymatic hydrolysis-based biomass-to-ethanol process. Production of cellulase enzyme proteins in large quantities using the fungus Trichoderma reesei requires understanding the dynamics of g...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(1999)66:1<1::aid-bit1>3.0.
更新日期:1999-01-01 00:00:00
abstract::Green fluorescent protein (GFP) was used to study the regulation of the galactose-inducible GAL1 promoter in yeast Saccharomyces cerevisiae strains. GFP was cloned into the pGAL110 vector and transformed into the yeast strains. Time course studies comparing culture fluorescence intensity and GFP concentration were con...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/1097-0290(20001020)70:2<187::aid-bit8>3.0.
更新日期:2000-10-20 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::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::Buddleja davidii is a unique biomass that has many attractive agroenergy features, especially its wide range of growth habitat. The anatomical characteristics of B. davidii were investigated before and after ethanol organosolv pretreatment (one of the leading pretreatment technologies) in order to further understand t...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.22884
更新日期:2010-12-01 00:00:00
abstract::The kinetics in batch culture of the acetone butanol fermentation by Clostridium acetobutylicum is compared on glucose, xylose, and mixtures of both sugars. The fastest initial growth and transition from an acid to a solvent metabolism occurs on glucose, with a final 62 g/L glucose conversion. On xylose, an initial sl...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260280203
更新日期:1986-02-01 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::Copolymers of N-isopropylacrylamide and N-acryloyl amino acid spacers of varying chain length were synthesized. p-Aminobenzamidine (PABA) was chemically linked to the pendant carboxyl groups of these polymers to obtain thermoprecipitating affinity polymers. The inhibition constant (Ki) of these polymers for trypsin de...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/(sici)1097-0290(19990820)64:4<418::aid-bit
更新日期:1999-08-20 00:00:00
abstract::A model previously developed to characterize enzymatic in activation behavior was used to explain the non-first-order biphasic and grace period phenomena that are often observed with oligomeric enzymes. Luciferase and urease were used as model enzyme such as luciferase, the oligomer initially dissociates reversibly in...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.260401118
更新日期:1992-12-20 00:00:00
abstract::The cometabolic transformation of 2,4,6-trinitrotoluene (TNT) by an immobilized Phanerochaete chrysosporium culture was investigated under different TNT and/or glycerol feeding conditions in a 5-L reactor. In the fed-batch feeding mode, as a result of four spiking events at an average feeding rate of 20 mg TNT L(-1) d...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
doi:10.1002/bit.1060
更新日期:2001-05-20 00:00:00