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Commonly, Global Positioning System (GPS)-based precise orbit determination (POD) of a low Earth orbiting (LEO) satellite is conducted by introducing fixed GPS orbits and clock corrections that were derived in a previous independent network solution using ground-based GPS receivers only. There have been a number of studies showing that the integration of LEO GPS observations can be advantageous in global network solutions, particularly when it comes to estimating geodetic parameters, such as the Earth's center-of-mass. There has been an increase in GPS data available from LEO CubeSats over the past few years, such as from the Spire satellites, which are equipped with dual-frequency GPS receivers. The goal of the present study is to determine how GPS observations collected by specific Spire satellites affect global network solutions when combined with GPS observations from ground stations of the International GNSS Service. To obtain a combined GPS-LEO solution, GPS observations collected from receivers of selected Spire satellites and additional scientific LEOs are used to obtain combined GPS-LEO solutions by performing one joint least-squares adjustment process. Using this method, LEO satellite orbit parameters are determined along with GPS orbit parameters and geodetic parameters, namely GNSS station coordinates, Earth rotation parameters (ERPs), and the Earth's center-of-mass. The influence of the Spire LEOs is assessed by analyzing different solutions that use GPS observations from different Spire and LEO satellites. Besides comparing the different global network solutions with one another, a comparison to a solution using only terrestrial GPS data is performed as well. As part of the quality assessment of the GPS-LEO solution, quality characteristics are analyzed, which are the geodetic parameters, orbit overlaps at arc boundaries, and formal errors determined for the estimated parameters. The results show that the estimation of the Earth's center-of-mass coordinates benefits from including GPS-LEO observations. The solution is more improved by integrating GPS-LEO observations from scientific LEOs than from GPS-Spire-included solutions. The analysis reveals that GPS orbits are improved using the LEO-integrated approach, while orbit misclosures of LEO and Spire trajectories currently indicate a decrease in LEO orbit precision due to LEO orbit modeling deficiencies. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A technology is proposed for processing of apatite concentrates by decomposition by phosphoric acid at 20°C in the presence of a sulfonic cation-exchange resin, defluorination of the obtained phosphoric acid, desorption of the sorbed cations with concentrated solutions of alkali metal salts, sequential hydrolytic precipitation of the thorium-enriched impurity cake and nonradioactive concentrate of carbonates of rare-earth and alkaline-earth elements, and regeneration of the sulfonic cation cation-exchange resin from the Na+ form to the H+ form. It is shown that the technology is also applicable for the processing of apatite concentrate with a high content of rare-earth elements and strontium. The technology ensures the recovery of all valuable components into commercial products while minimizing the consumption of reagents and energy, the amount of generated waste, and the environmental pollution. [ABSTRACT FROM AUTHOR]

Continuous precipitation coupled with continuous tangential flow filtration is a cost‐effective alternative for the capture of recombinant antibodies from crude cell culture supernatant. The removal of surge tanks between unit operations, by the adoption of tubular reactors, maintains a continuous harvest and mass flow of product with the advantage of a narrow residence time distribution (RTD). We developed a continuous process implementing two orthogonal precipitation methods, CaCl2 precipitation for removal of host‐cell DNA and polyethylene glycol (PEG) for capturing the recombinant antibody, with no influence on the glycosylation profile. Our lab‐scale prototype consisting of two tubular reactors and two stages of tangential flow microfiltration was continuously operated for up to 8 days in a truly continuous fashion and without any product flow interruption, both as a stand‐alone capture and as an integrated perfusion‐capture. Furthermore, we explored the use of a negatively charged membrane adsorber for flow‐through anion exchange as first polishing step. We obtained a product recovery of approximately 80% and constant product quality, with more than two logarithmic reduction values (LRVs) for both host‐cell proteins and host‐cell DNA by the combination of the precipitation‐based capture and the first polishing step. [ABSTRACT FROM AUTHOR]

Abstract Continuous precipitation coupled with continuous tangential flow filtration is a cost‐effective alternative for the capture of recombinant antibodies from crude cell culture supernatant. The removal of surge tanks between unit operations, by the adoption of tubular reactors, maintains a continuous harvest and mass flow of product with the advantage of a narrow residence time distribution (RTD). We developed a continuous process implementing two orthogonal precipitation methods, CaCl2 precipitation for removal of host‐cell DNA and polyethylene glycol (PEG) for capturing the recombinant antibody, with no influence on the glycosylation profile. Our lab‐scale prototype consisting of two tubular reactors and two stages of tangential flow microfiltration was continuously operated for up to 8 days in a truly continuous fashion and without any product flow interruption, both as a stand‐alone capture and as an integrated perfusion‐capture. Furthermore, we explored the use of a negatively charged membrane adsorber for flow‐through anion exchange as first polishing step. We obtained a product recovery of approximately 80% and constant product quality, with more than two logarithmic reduction values (LRVs) for both host‐cell proteins and host‐cell DNA by the combination of the precipitation‐based capture and the first polishing step.

BACKGROUND: The scale‐up of Escherichia coli bioprocesses for production of recombinant proteins in the biopharmaceutical industry can affect process performance due to gradients occurring at production scale. The main objective of this study was to investigate the effect of scale‐related process heterogeneities on properties of high‐cell‐density fermentation broths. Two industrially relevant Escherichia coli strains, BL21(DE3) and HMS174(DE3), were used for production of antibody fragments (Fab). To generate these heterogeneities, we used a scale‐down device for cell cultivation, which mimics conditions of production scale (>1000 L) in a 20 L laboratory scale. This setup helps to evaluate the impact of process scale‐up on the resulting fermentation broth properties relevant for primary recovery. RESULTS: We found differences in broth viscosity between the two strains, but also between the standard laboratory‐scale and the scale‐down cultivations used. An increase in cell size was measured in scale‐down cultivations with three orthogonal methods, using scanning electron microscopy, dynamic light scattering and a dispersion analyzer. Strong hints for an altered agglomeration tendency of the cells after scale‐down cultivations were found by measurement of settling velocity and viscoelasticity of the fermentation broth. CONCLUSIONS: In this work, industrially relevant fermentation broths of Escherichia coli cells producing Fab were characterized and represent a relevant basis for rational design of downstream processing operations. The findings show that scale‐related process heterogeneities can alter the phenotype of Escherichia coli cells and thus alter fermentation broth properties relevant for primary recovery. Considering scale‐up effects in upstream processing reflected in downstream processing will help to optimize the entire bioproduction chain in the future. © 2023 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

At present, some mapping satellites, such as GaoFen-7 and ZiYuan3-03, are equipped with both optical stereo cameras and laser altimeters that can synchronously obtain stereo images and sparse ground laser altimetry points (LAPs). To effectively improve the geometric accuracy of these satellite stereo images, this study proposed an integrated processing method for LAPs and stereo images derived from the same satellite. This method makes full use of the advantages of synchronously obtaining stereo images and LAPs, and designs measurement technology for accurate pixel coordinates of LAPs in stereo images, which works toward solving a technical difficulty that has restricted their integration to achieve higher accuracy. The method also constructs a combined block adjustment model of LAPs and stereo images. We selected 70 GaoFen-7 stereo images and 463 GaoFen-7 LAPs from Hebei Province, China, and 12 ZiYuan3-03 stereo images and 81 ZiYuan3-03 LAPs from Heilongjiang Province, China, to conduct integrated processing experiments. The vertical accuracy of the GaoFen-7 images in all types of terrain were improved substantially and reached the accuracy requirements of 1:10,000 (even 1:5000) scale mapping in China. The vertical accuracy of the ZiYuan3-03 images in various terrain areas were also improved markedly, satisfying the accuracy requirement of 1:50,000 scale mapping. These experimental results indicate that the working mode of synchronously obtaining LAPs and stereo images using the same satellite is advanced, and the proposed method is correct and effective. [ABSTRACT FROM AUTHOR]

Very Long Baseline Interferometry (VLBI) intensive (INT) sessions are critical for the rapid determination and densification of Universal Time 1‐Coordinate Universal Time (UT1‐UTC), which plays an important role in satellite geodesy and space exploration missions and is not predictable over longer time scales. Due to the limited observation geometry of INT sessions with two to three stations observing about 1 hr, tropospheric gradients cannot be estimated, which degrades the UT1‐UTC precision. We investigate the impact of tropospheric ties at Global Navigation Satellite Systems (GNSSs) and VLBI co‐located stations in INT sessions from 2001 to 2021. VLBI and GNSS observations are combined on the observation level. The results are evaluated by using both UT1‐UTC and Length of Day (LOD) from consecutive sessions. We demonstrate a better agreement of 10%–30% when comparing the derived LOD to GNSS LOD for INT1, INT2, and VGOS‐2 sessions; whereas, the agreement is not improved when directly comparing UT1‐UTC to the IERS Earth Orientation Parameters (EOPs) product, potentially because INT sessions also contribute to IERS EOP products. The major impact comes from tropospheric gradient ties, whereas applying zenith delay ties does not improve or even deteriorate UT1‐UTC agreement. Gradient ties also introduce systematic biases in UT1‐UTC by around −3 to −5 μs, except for the Russian INT sessions. Regression analysis shows that the east gradient introduces systematic effects in UT1‐UTC for sessions involving Germany and USA (Hawaii), whereas for Germany–Japan and Russian sessions, the north gradient also contributes systematically. Plain Language Summary: Universal Time 1‐Coordinate Universal Time (UT1‐UTC) gives the time difference of UT1, defined by Earth's rotation, and UTC, defined by atomic clocks. UT1‐UTC is essential for real‐time navigation and space exploration. The variation of the first‐order negative time derivative of UT1‐UTC, Length of Day (LOD), is induced by mass redistribution, including tides of the solid Earth and oceans, the liquid core of the Earth and atmospheric variation, and climate events such as El Niño. Very Long Baseline Interferometry (VLBI) observing active galactic nuclei is the only space geodetic technique that can determine UT1‐UTC unambiguously. The 1‐hr intensive (INT) sessions, designed for the rapid determination and densification of UT1‐UTC, are performed daily with two VLBI radio telescopes. Due to the limited observation geometry, tropospheric gradients cannot be modeled in INT sessions, deteriorating UT1‐UTC estimates. We demonstrate an improvement of 10%–30% in LOD by applying tropospheric ties at VLBI and Global Navigation Satellite Systems co‐locations, especially the tropospheric gradients ties. Tropospheric gradient ties also introduce a systematic effect of −3 to −5 μs on UT1‐UTC, especially the east gradient. Our study shows that tropospheric ties should be adopted in future VLBI analysis for optimal UT1‐UTC products. Key Points: Tropospheric ties are applied in a Global Navigation Satellite System–Very Long Baseline Interferometry (GNSS–VLBI) integrated solution analyzing VLBI intensive (INT) sessions from 2001 to 2021Length of Day (LOD) of IVS INT sessions shows a better agreement by 10%–30% when compared to GNSS LOD product, mainly due to gradient tiesGradient ties, especially the east one, introduce systematic biases of −3 to −5 μs in Universal Time 1‐Coordinate Universal Time of IVS INT sessions [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At present, some mapping satellites, such as GaoFen-7 and ZiYuan3-03, are equipped with both optical stereo cameras and laser altimeters that can synchronously obtain stereo images and sparse ground laser altimetry points (LAPs). To effectively improve the geometric accuracy of these satellite stereo images, this study proposed an integrated processing method for LAPs and stereo images derived from the same satellite. This method makes full use of the advantages of synchronously obtaining stereo images and LAPs, and designs measurement technology for accurate pixel coordinates of LAPs in stereo images, which works toward solving a technical difficulty that has restricted their integration to achieve higher accuracy. The method also constructs a combined block adjustment model of LAPs and stereo images. We selected 70 GaoFen-7 stereo images and 463 GaoFen-7 LAPs from Hebei Province, China, and 12 ZiYuan3-03 stereo images and 81 ZiYuan3-03 LAPs from Heilongjiang Province, China, to conduct integrated processing experiments. The vertical accuracy of the GaoFen-7 images in all types of terrain were improved substantially and reached the accuracy requirements of 1:10,000 (even 1:5000) scale mapping in China. The vertical accuracy of the ZiYuan3-03 images in various terrain areas were also improved markedly, satisfying the accuracy requirement of 1:50,000 scale mapping. These experimental results indicate that the working mode of synchronously obtaining LAPs and stereo images using the same satellite is advanced, and the proposed method is correct and effective.

• An integrated microfluidic platform was developed to mimic the manufacturing of a target protein. • The microfluidic chip consists of a microbioreactor, a chemical lysis and ATPS module, allowing the integration of upstream with downstream processing. • Integrated device was continuously operated for 8 days with uniform protein concentration. • The multimodular microfluidic device developed allows for the screening and optimization of biologicals continuous production and purification conditions. Microfluidic devices have been increasingly used as tools to accelerate the development of new biomanufacturing methods, given their ability to test a large set of variables in a short time, with minimal reagent consumption. However, while being able to expedite a bioprocess design, the modular aspect of these microfluidic devices has not been systematically explored, with most applications focusing on single unitary operations. Integrated continuous bioprocessing has the potential to reduce cost, optimize yield and reduce footprint as compared to batch operation. In this work an integrated microfluidic device for continuous processing is developed and qualitatively shows connected different unit operations able to produce GFP in microbioreactor, extract out of cells in lysis module and finally concentrate in ATPs module. The integrated system developed herein consists of a micro-chemostat module to produce a target protein in continuous mode, a chemical cell lysis module for protein release and a module to purify and concentrate the protein using aqueous two-phase systems (ATPS). In this way, it is possible to screen multiple conditions for each operation and evaluate their combined effect on the final product. A recombinant Escherichia coli (E. coli) strain producing green fluorescent protein (GFP) was used as a model system, which allows for GFP production, lysis efficiency and partition coefficient to be evaluated by fluorescence microscopy. Experiments were done for over a week by continuously supplying medium and monitoring the GFP production by fluorescence intensity. A chemical lysis solution B-PER® was used for continuous lysis and afterwards the extracted GFP was clarified and concentrated in the PEG-rich phase of a PEG/phosphate ATPS with a partition coefficient of 2. As the integrated device is working in continuous mode it could be integrated with further downstream processing modules. [ABSTRACT FROM AUTHOR]

Virus-like particles (VLPs) are emerging nanoscale protein assemblies applied as prophylactic vaccines and in development as therapeutic vaccines or cargo delivery systems. Downstream processing (DSP) of VLPs comes both with challenges and opportunities, depending on the complexity and size of the structures. Filtration, precipitation/re-dissolution and size-exclusion chromatography (SEC) are potent technologies exploiting the size difference between product and impurities. In this study, we therefore investigated the integration of these technologies within a single unit operation, resulting in three different processes, one of which integrates all three technologies. VLPs, contained in clarified lysate from Escherichia coli, were precipitated by ammonium sulfate, washed, and re-dissolved in a commercial cross-flow filtration (CFF) unit. Processes were analyzed for yield, purity, as well as productivity and were found to be largely superior to a reference centrifugation process. Productivity was increased 2.6-fold by transfer of the wash and re-dissolution process to the CFF unit. Installation of a multimodal SEC column in the permeate line increased purity to 96% while maintaining a high productivity and high yield of 86%. In addition to these advantages, CFF-based capture and purification allows for scalable and disposable DSP. In summary, the developed set-up resulted in high yields and purities, bearing the potential to be applied as an integrated process step for capture and purification of in vivo-assembled VLPs and other protein nanoparticles.

The precise orbit determination (POD) of Global Navigation Satellite System (GNSS) satellites and low Earth orbiters (LEOs) are usually performed independently. It is a potential way to improve the GNSS orbits by integrating LEOs onboard observations into the processing, especially for the developing GNSS, e.g., Galileo with a sparse sensor station network and Beidou with a regional distributed operating network. In recent years, few studies combined the processing of ground- and space-based GNSS observations. The integrated POD of GPS satellites and seven LEOs, including GRACE-A/B, OSTM/Jason-2, Jason-3 and, Swarm-A/B/C, is discussed in this study. GPS code and phase observations obtained by onboard GPS receivers of LEOs and ground-based receivers of the International GNSS Service (IGS) tracking network are used together in one least-squares adjustment. The POD solutions of the integrated processing with different subsets of LEOs and ground stations are analyzed in detail. The derived GPS satellite orbits are validated by comparing with the official IGS products and internal comparison based on the differences of overlapping orbits and satellite positions at the day-boundary epoch. The differences between the GPS satellite orbits derived based on a 26-station network and the official IGS products decrease from 37.5 to 23.9 mm ( 34 % improvement) in 1D-mean RMS when adding seven LEOs. Both the number of the space-based observations and the LEO orbit geometry affect the GPS satellite orbits derived in the integrated processing. In this study, the latter one is proved to be more critical. By including three LEOs in three different orbital planes, the GPS satellite orbits improve more than from adding seven well-selected additional stations to the network. Experiments with a ten-station and regional network show an improvement of the GPS satellite orbits from about 25 cm to less than five centimeters in 1D-mean RMS after integrating the seven LEOs. [ABSTRACT FROM AUTHOR]

The paper presents the results of a research on the catalytic properties of a contact substance obtained by integrated processing of high-magnesia sideritic ores of the Bakalskoye deposit (Chelyabinsk region, Russian Federation (RF), the reserves are of over 1 billion tones). The investigated material demonstrates catalytic activity in the process of carbon dioxide gasification of the bituminous coal of the Raspadskoye deposit, Kuznetsk coal basin, RF. The experimental results obtained show that the use of a contact substance based on the products of integrated processing of high-magnesia siderites results in an increase of the gasification rate by a factor of 2 - 4 as compared with the non-catalytic process. [ABSTRACT FROM AUTHOR]

Background: Clavulanic acid is an important beta-lactamase inhibitor produced as a secondary metabolite by the actinomycete Streptomyces clavuligerus. Clavulanic acid is chemically unstable; therefore, it is degraded during bacterial cultivation. In this work, the adsorbents clinoptilolite, activated carbon, calcined hydrotalcite, and Amberlite IRA 400 anionic exchange resin were studied in terms of their ability to adsorb clavulanic acid during extractive fermentation, in order to prevent product degradation and avoid product concentrations reaching inhibitory levels. Adsorption assays were used to investigate the effect of pH, and the decrease in the clavulanic acid concentration in the culture broth was measured for each adsorbent. Results: IRA 400 was found to be most effective, with 78% adsorption of clavulanic acid. The maximum production of clavulanic acid in Erlenmeyer flask cultures increased 86% in terms of mass of CA, and 248% in cumulative CA concentration, with the use of Amberlite IRA 400 as adsorbent in extractive fermentation, compared to control fermentation performed without product removal. Conclusions: The results indicated that extractive fermentation using a solid phase could be an important way of enhancing clavulanic acid titers. It was also possible to show that clavulanic acid acts as an inhibitor of its own synthesis.

In the past decades, research was carried out to find cost-efficient alternatives to Protein A chromatography as a capture step in monoclonal antibody (mAb) purification processes. In this work, polyethylene glycol (PEG) precipitation has shown promising results in the case of mAb yield and purity. Especially with respect to continuous processing, PEG precipitation has many advantages, like low cost of goods, simple setup, easy scalability, and the option to handle perfusion reactors. Nevertheless, replacing Protein A has the disadvantage of renouncing a platform unit operation as well. Furthermore, PEG precipitation is not capable of reducing high molecular weight impurities (HMW) like aggregates or DNA. To overcome these challenges, an integrated process strategy combining PEG precipitation with cation-exchange chromatography (CEX) for purification of a mAb is presented. This work discusses the process strategy as well as the associated fast, easy, and material-saving process development platform. These were implemented through the combination of high-throughput methods with empirical and mechanistic modeling. The strategy allows the development of a common batch process. Additionally, it is feasible to develop a continuous process. In the presented case study, a mAb provided from cell culture fluid (HCCF) was purified. The precipitation and resolubilization conditions as well as the chromatography method were optimized, and the mutual influence of all steps was investigated. A mAb yield of over 95.0% and a host cell protein (HCP) reduction of over 99.0% could be shown. At the same time, the aggregate level was reduced from 3.12% to 1.20% and the DNA level was reduced by five orders of magnitude. Furthermore, the mAb was concentrated three times to a final concentration of 11.9 mg/mL. [ABSTRACT FROM AUTHOR]

The pressures to efficiently produce complex biopharmaceuticals at reduced costs are driving the development of novel techniques, such as in downstream processing with straight-through processing (STP). This method involves directly and sequentially purifying a particular target with minimal holding steps. This work developed and compared six different 3-step STP strategies, combining membrane adsorbers, monoliths, and resins, to purify a large, complex, and labile glycoprotein from Chinese hamster ovary cell culture supernatant. The best performing pathway was cation exchange chromatography to hydrophobic interaction chromatography to affinity chromatography with an overall product recovery of up to 88% across the process and significant clearance of DNA and protein impurities. This work establishes a platform and considerations for the development of STP of biopharmaceutical products and highlights its suitability for integration with single-use technologies and continuous production methods. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:931-940, 2017 [ABSTRACT FROM AUTHOR]

The cost-competitiveness of a refining process using wine lees for the production of ethanol, antioxidant-rich extract, calcium tartrate and yeast cells was evaluated in this study via process design and preliminary techno-economic evaluation. Process design was performed using the commercial process simulator UniSim (Honeywell). A sensitivity analysis was carried out to estimate the minimum selling price of the antioxidant-rich extract that should be achieved at different plant capacities in order to develop a profitable wine lees refining process. Minimum selling prices of the antioxidant-rich extract in the range of 122–11.06 $/kg are required in order to develop profitable refining schemes with wine lees processing capacities of 500 to 5000 kg/h considering 120 days of annual operating time. The final products could be used in various industrial segments including food, feed, chemical and cosmetic industries. [ABSTRACT FROM AUTHOR]

Crude enzyme produced via solid state fermentation using the fungal strain Aspergillus oryzae was used to lyse cells of Cupriavidus necator, enabling the recovery of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), P(3HB-co-12mol% 3HV). A central composite design was employed in order to optimize the temperature and the pH value leading to the highest lysis of Cupriavidus necator cells (88.9 ± 0.4%) and the optimal hydrolysis of protein contained in bacterial cells. Enzymatic lysis of bacterial cells was also carried out at the optimum temperature and uncontrolled pH value leading to P(3HB-co-12mol% 3HV) recovery yield and purity of 98% and 96.7%, respectively. The bacterial cell lysate obtained after the separation of P(3HB-co-12mol% 3HV) granules was evaluated as nutrient-rich supplement together with crude glycerol for the production of poly(3-hydroxybutyrate) in shake flask cultures. This novel downstream separation process could be integrated in a sunflower-based biorefinery reducing the cost of poly(hydroxyalkanoate) recovery and fermentation medium formulation. [ABSTRACT FROM AUTHOR]

Waste biomass is generated during the conservation management of semi-natural habitats, and represents an unused resource and potential bioenergy feedstock that does not compete with food production. Thermogravimetric analysis was used to characterise a representative range of biomass generated during conservation management in Wales. Of the biomass types assessed, those dominated by rush ( Juncus effuses ) and bracken ( Pteridium aquilinum ) exhibited the highest and lowest volatile compositions respectively and were selected for bench scale conversion via fast pyrolysis. Each biomass type was ensiled and a sub-sample of silage was washed and pressed. Demineralization of conservation biomass through washing and pressing was associated with higher oil yields following fast pyrolysis. The oil yields were within the published range established for the dedicated energy crops miscanthus and willow. In order to examine the potential a multiple output energy system was developed with gross power production estimates following valorisation of the press fluid, char and oil. If used in multi fuel industrial burners the char and oil alone would displace 3.9 × 10 5 tonnes per year of No. 2 light oil using Welsh biomass from conservation management. Bioenergy and product development using these feedstocks could simultaneously support biodiversity management and displace fossil fuels, thereby reducing GHG emissions. Gross power generation predictions show good potential. [ABSTRACT FROM AUTHOR]

The impact of foaming on cell growth and surfactin production by Bacillus subtilis during a foam recovery process has been evaluated for the first time. First, a small-scale batch foaming approach was employed to assess whether fermentation performance is affected when B. subtilis cells are subjected to foaming. Results showed that foaming stimulated surfactin production, resulting in 1.13-fold higher surfactin producing abilities (17 mg/g h) and higher biomass yields (∼0.27 g/g) in comparison to fermentation performances achieved by using cells not subjected to foaming. The synergistic combination of glucose-limited conditions and foaming additionally triggered the surfactin yields on glucose (0.1 g/g) and titers (0.41 g/L), attaining a volumetric surfactin productivity of 17 mg/L h under batch cultivation. Second, continuous foam fractionation experiments enabled controlled segregation of cells by foaming. This revealed that foamed cells displayed 2-fold higher specific surfactin production rates (16 mg/g h) than non-foamed cells (8 mg/g h). Furthermore, cell growth, surfactin titers, and volumetric productivities were further enhanced by re-using spent B. subtilis cells from the column overflow. The present study demonstrated for the first time the concept of using foam fractionation for improving cellular growth while triggering surfactin production by recycling the spent B. subtilis cells resulted from a foam recovery process. [ABSTRACT FROM AUTHOR]

In this study, fungal membrane bioreactor (FMBR) and semiconductor photocatalytic membrane reactor (PMR) were used in order to test the efficiency of integrated fungal biodegradation and photocatalytic degradation of textile wastewater from reactive washing processes. It was found that color removal and chemical oxygen demand (COD) reduction efficiencies were 88% and 53% for photocatalytic degradation, respectively. TiO 2 and ZnO were tested as semiconductor catalysts in the PMR and TiO 2 showed better efficiencies than ZnO for both color and COD removal. However, it was attained that color removal and COD reduction efficiencies were about 56% and 60% for fungal biodegradation using Phanerochaete chrysosporium , respectively. Moreover, integrated system in which photocatalytic degradation was employed as a post-treatment application after fungal biodegradation process achieved high removal efficiencies for color and COD removal as 93% and 99%, respectively. [ABSTRACT FROM AUTHOR]

ABSTRACT Fusion-tag affinity chromatography is a key technique in recombinant protein purification. Current methods for protein recovery from mammalian cells are hampered by the need for feed stream clarification. We have developed a method for direct capture using immobilized metal affinity chromatography (IMAC) of hexahistidine (His6) tagged proteins from unclarified mammalian cell feed streams. The process employs radial flow chromatography with 300-500 μm diameter agarose resin beads that allow free passage of cells but capture His-tagged proteins from the feed stream; circumventing expensive and cumbersome centrifugation and/or filtration steps. The method is exemplified by Chinese Hamster Ovary (CHO) cell expression and subsequent recovery of recombinant His-tagged carcinoembryonic antigen (CEA); a heavily glycosylated and clinically relevant protein. Despite operating at a high NaCl concentration necessary for IMAC binding, cells remained over 96% viable after passage through the column with host cell proteases and DNA detected at ∼8 U/mL and 2 ng/μL in column flow-through, respectively. Recovery of His-tagged CEA from unclarified feed yielded 71% product recovery. This work provides a basis for direct primary capture of fully glycosylated recombinant proteins from unclarified mammalian cell feed streams. Biotechnol. Bioeng. 2016;113: 130-140. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Foam fractionation is an adsorptive separation method that occurs on the liquid-foam interface, when rising bubbles removes active-surface compounds distributed throughout the continuous liquid phase. The formed foam is allowed to build up above the liquid, where, a drainage process results in further enrichment of the surface-active species. In this work, foam fractionation was used the concentration of surfactin from a fermentation broth. The biosurfactant was produced in a culture of Bacillus sp. ITP-001 and the bioreactor was integrated to a fractionation column aiming at the saving of steps in the purification of the product. The production of foam was controlled by fixed aeration and agitation rates. An experimental planning design method of type 2 2 was used in the experiments set up. The maximum value of surfactin concentration was acquired in the operation with minimum values of aeration and agitation rates. The average surfactin enrichment in these operation conditions reached the value of 28 times and the mass recovery was 94%. The integration of the bioreactor and the separation device was demonstrated as a simple and practical method for surfactin concentration using Bacillus sp. ITP-001, a production method. Assays of antimicrobial activity indicated that the produced surfactin is a powerful antimicrobial agent against several pathogenic microorganisms ( Escherichia coli , Candida albicans , Fusarium sp.). [ABSTRACT FROM AUTHOR]

Highly porous polyetherimide (PEI) microparticles achieved by a spraying/coagulation process are candidate absorber materials for apheresis applications. Hydrophobic PEI surfaces tend to be rapidly coated with proteins when in contact with blood. Therefore, a hydrophilic modification of such particles is required. In this study, we explored the formation of porous, surface functionalized PEI microparticles by low molecular weight polyethyleneimine (Pei) or potassium hydroxide (KOH) in an integrated process combining chemical modification and particle formation. The integrated process resulted in smaller microparticles with diameters of 70 to 80 μm compared to the chemical twostep process. All particles exhibited similar bulk densities, ranging from 0.09 to 0.015 g cm-3, and average pore sizes around 180-250 nm. A successful modification of the particles' surface by both processing approaches could be confirmed by X-ray photoelectron spectroscopy measurements and microwetting experiments, where hydrophilic advancing contact angles of 57° to 64° were determined. Integrated particle processing further resulted in changes of the bulk properties, i.e. molecular weight, thermal decomposition behavior or glass transition temperature. Hydrophilic modified PEI microparticles have been successfully prepared by different approaches. In a next step their absorption capacity for uremic toxins will be investigated with regard to a potential application in blood detoxification. [ABSTRACT FROM AUTHOR]