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关键词： Ambr250   Bioreactor   Vessel   Bioprocessing   Automation   hMSC   T-cell  

摘要： The emergence of cell and gene therapies has generated significant interest in their clinical and commercial potential. However, these therapies are prohibitively expensive to manufacture and can require extensive time for development due to our limited process knowledge and understanding. The automated ambr250 (R) stirred-tank bioreactor platform provides an effective platform for high-throughput process development. However, the original dual pitched-blade 20 mm impeller and baffles proved sub-optimal for cell therapy candidates that require suspension of microcarriers (e.g. for the culture of adherent human mesenchymal stem cells) or other particles such as activating Dynabeads (R) (e.g. for the culture of human T-cells). We demonstrate the development of a new ambr250 (R) stirred-tank bioreactor vessel which has been designed specifically to improve the suspension of microcarriers/beads and thereby improve the culture of such cellular systems. The new design is unbaffled and has a single, larger elephant ear impeller. We undertook a range of engineering and physical characterizations to determine which vessel and impeller configuration would be most suitable for suspension based on the minimum agitation speed (N-JS) and associated specific power input (P/V)(JS). A vessel (diameter, T, = 60 mm) without baffles and incorporating a single elephant ear impeller (diameter 30 mm and 45 degrees pitch-blade angle) was selected as it had the lowest (P/V)(JS) and therefore potentially, based on Kolmogorov concepts, was the most flexible system. These experimentally-based conclusions were further validated firstly with computational fluid dynamic (CFD) simulations and secondly experimental studies involving the culture of both T-cells with Dynabeads (R) and hMSCs on microcarriers. The new ambr250 (R) stirred-tank bioreactor successfully supported the culture of both cell types, with the T-cell culture demonstrating significant improvements compared to the original ambr250

关键词： Neurospora intermedia   Semi-continuous bioreactor   Plug flow bioreactor   Solid-state fermentation   Bread waste  

摘要： Stale bread, one of the major food wastes, holds great potential to produce new food products by solid-state fermentation using the edible filamentous fungus Neurospora intermedia. Yet, this process is limited to small-scale batch production. In this study, a plug-flow bioreactor was developed and successfully operated semicontinuously without addition of external inoculum. Two critical process parameters namely residence time and inoculum-to-substrate ratio (ISR) were studied in two experimental set-ups, 48 h and ISR 10:65 or 24 h and 20:55. The fermentation performance was assessed by the CO2 evolution rate and starch degradation in the substrate. Both experiments resulted in a relatively stable CO2 evolution rate up to 10 days and the starch content was reduced from 65 % in bread to 40.6 % and 43.2 %, respectively, in the product. Performance of the plug-flow bioreactor was compared to batch fermentation in tray bioreactors using the same ratio of inoculum. No significant differences of the final starch content were observed between the bioreactors, which indicate improved productivity by the semi-continuous process compared to the batch. The fungal biomass yield was calculated to range from 0.12 to 0.5 mol C-biomass/mole C-substrate . A material balance of the process revealed that 220 g dry bread and 200 ml water were required to produce 400 g fermented product with a fungal biomass content of 15 % in 24 h.

关键词： bioprocess monitoring   chemometrics   multidimensional fluorescence   polarization   process analytical technology   protein  

摘要： Protein quantification during bioprocess monitoring is essential for biopharmaceutical manufacturing and is complicated by the complex chemical composition of the bioreactor broth. Here we present the early-stage development and optimization of a polarized total synchronous fluorescence spectroscopy (pTSFS) method for protein quantification in a hydrolysate-protein model (mimics clarified bioreactor broth samples) using a standard benchtop laboratory fluorometer. We used UV transmitting polarizers to provide wider range pTSFS spectra for screening of the four different TSFS spectra generated by the measurement: parallel (||), perpendicular (perpendicular to), unpolarized (T) intensity spectra and anisotropy maps. TSFS|| (parallel polarized) measurements were the best for protein quantification compared to standard unpolarized measurements and the Bradford assay. This was because TSFS|| spectra had a better analyte signal to noise ratio (SNR), due to the anisotropy of protein emission. This meant that protein signals were better resolved from the background emission of small molecule fluorophores in the cell culture media. SNR of >5000 was achieved for concentrations of bovine serum albumin/yeastolate 1.2/10 g L-1 with TSFS||. Optimization using genetic algorithm and interval partial least squares based variable selection enabled reduction of spectral resolution and number of excitation wavelengths required without degrading performance. This enables fast (<3.5 min) online/at-line measurements, and the method had an LOD of 0.18 g L-1 and high accuracy with a predictive error of <9%.

关键词： red blood cells   hiPSC   microcarrier  

摘要： 6

关键词： Decolorization   Moving bed-membrane bioreactor   Cathodic electro-oxidation   TiO2/Graphite   TiO2/Platine   TiO2/TiO2   TiO2/RuO2  

摘要： This study is carried out to investigate the effect of the cathodic contribution in the performance of electro-oxidation process for decolorization of the textile wastewater effluent pre-treated with a lab-scale moving bed-membrane bioreactor. For this purpose, titanium dioxide (TiO2) was used as anode electrode and four different cathodic electrode materials: Graphite, TiO2, TiO(2-)coated Platine, and TiO(2-)coated ruthenium dioxide (RuO2) (namely RuO2) were tested and compared for their color removal efficiencies. Besides, the optimization parameters that affect color removal in correspondence to the electrode materials, such as applied current, electrolysis time, and pH were studied. In this context, the optimum parameters for each electrode material were selected, and the color removal percentages were found as 92.95%, 91.58%, 91.40%, and 89.17% for TiO2/Graphite, TiO2/Platine, TiO2/TiO2, and TiO2/RuO2, respectively. Finally, the operational cost for each of the tested cathodic electrode materials was calculated in each of the studied optimization parameters making it easier and practical for the selection and evaluation of the electrode materials by the readers. The correlation coefficients (R-2) were 81.2%, 87.1%, 86.7%, and 88.6% respectively as a result of the optimization study using the nonlinear regression modeling.

关键词： CHO   k(L)a   microbioreactor   micro‐   mixing   oxygen transfer coefficient   T cells  

摘要： Bioprocess optimization for cell-based therapies is a resource heavy activity. To reduce the associated cost and time, process development may be carried out in small volume systems, with the caveat that such systems be predictive for process scale-up. The transport of oxygen from the gas phase into the culture medium, characterized using the volumetric mass transfer coefficient, k(L)a, has been identified as a critical parameter for predictive process scale-up. Here, we describe the development of a 96-well microplate with integrated Redbud Posts to provide mixing and enhanced k(L)a. Mixing in the microplate is characterized by observation of dyes and analyzed using the relative mixing index (RMI). The k(L)a is measured via dynamic gassing out method. Actuating Redbud Posts are shown to increase rate of planar homogeneity (2 min) verse diffusion alone (120 min) and increase oxygenation, with increasing stirrer speed (3500-9000 rpm) and decreasing fill volume (150-350 mu L) leading to an increase in k(L)a (4-88 h(-1)). Significant increase in Chinese Hamster Ovary growth in Redbud Labs vessel (580,000 cells mL(-1)) versus the control (420,000 cells mL(-1));t(12.814) = 8.3678, p <= .001), and CD4(+) Naive cell growth in the microbioreactor indicates the potential for this technology in early stage bioprocess development and optimization.

关键词： batch fermentation   bioreactors   Debaryomyces hansenii   non‐   conventional yeast   osmotic stress   salt tolerance  

摘要： Debaryomyces hansenii is traditionally described as a halotolerant non-conventional yeast and has served as a model organism for the study of osmotolerance and salt tolerance mechanisms in eukaryotic systems for the past 30 years. However, unraveling of D. hansenii's biotechnological potential has always been difficult due to the persistent limitations in the availability of efficient molecular tools described for this yeast. Additionally, there is a lack of consensus and contradictory information along the recent years that limits a comprehensive understanding of its central carbon metabolism, mainly due to a lack of physiological studies in controlled and monitored environments. Moreover, there is little consistency in the culture conditions (media composition, temperature, and pH among others) used by different groups, which makes it complicated when trying to get prevalent conclusions on behavioral patterns. In this work, we present for the first time a characterization of D. hansenii in batch cultivations using highly controlled lab-scale bioreactors. Our findings contribute to a more complete picture of the central carbon metabolism and the external pH influence on the yeast's ability to tolerate high Na+ and K+ concentrations, pointing to a differential effect of both salts, as well as a positive effect in cell performance when low environmental pH values are combined with a high sodium concentration in the media. Finally, a novel survival strategy at very high salinity (2 M) is proposed for this yeast, as well as potential outcomes for its use in industrial biotechnology applications. Take Away High salt concentrations stimulate respiration in Debaryomyces hansenii. Sodium exerts a stronger positive impact on cell performance than potassium. mu(max) is higher at a combination of low pH, high salt, and high temperature. Concentrations of 2 M salt result in slower growth but increased biomass yield. The positive effect of salts is enhanced at low glucose conce

关键词： CHO cells   continuous‐   flow stirred tank bioreactor   hydrocyclone   linked bioreactors   perfusion  

摘要： A continuous Chinese hamster ovary (CHO) cell culture process comprised of a highly proliferative N-1 perfusion bioreactor utilizing a hydrocyclone as a cell retention device linked to a production continuous-flow stirred tank reactor (CSTR) is presented. The overflow stream from the hydrocyclone, which is only partially depleted of cells, provides a continuous source of high viability cells from the N-1 perfusion bioreactor to the 5-20 times larger CSTR. Under steady-state conditions, this linked-bioreactor system achieved a peak volumetric productivity of 0.96 g/L/day, twofold higher than the optimized fed-batch process. The linked bioreactor system using a hydrocyclone was also shown to be 1.8-3.1 times more productive than a dual, cascading CSTR system without cell retention.

关键词： iCELLis   OptiPEAK   Aber  

摘要： 1112

关键词： Automated aseptic sampling device   Continuous monitoring   Process Analytical Technology  

摘要： 1206