Efficient production of l-asparaginase from Bacillus licheniformis with low-glutaminase activity: Optimization, scale up and acrylamide degradation studies

2012 ◽  
Vol 125 ◽  
pp. 11-16 ◽  
Author(s):  
Richi V. Mahajan ◽  
Saurabh Saran ◽  
Karthikeya Kameswaran ◽  
Vinod Kumar ◽  
R.K. Saxena
Keyword(s):  
Bacillus Licheniformis ◽  
Scale Up ◽  
Efficient Production ◽  
Degradation Studies ◽  
Glutaminase Activity ◽  
Activity Optimization

scholarly journals Mass Transfer Features of Wavy-Bottomed Cascade Photobioreactors

2021 ◽  
Vol 5 (4) ◽  
pp. 86
Author(s):  
Monica Moroni ◽  
Giorgia Sed ◽  
Agnese Cicci ◽  
Barbara Mazzarotta ◽  
Nicola Verdone ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Energy Efficient ◽  
Scale Up ◽  
Biomass Concentration ◽  
Efficient Production ◽  
Light Path ◽  
High Biomass ◽  
Growth Limitation ◽  
Microalgae Biomass ◽  
High Biomass Concentration

It has been suggested that the energy-efficient production of microalgae biomass can be more easily obtained in short light path photobioreactors that can be operated at high biomass concentration. On the downside, however, high biomass concentrations also require an efficient gas exchange rate to avoid metabolic growth limitation or inhibition. A cascade photobioreactor featuring a thin liquid layer flowing down a sloping, wavy-bottomed surface can be operated at a biomass concentration that is much higher compared to most usual open-type equipment. Liquid flow, upon investigation, proved to exhibit peculiar “local recirculation” hydrodynamics, potentially conducive to the mixing of superficial and deep zones of the photobioreactor. Mass transfer coefficient represents a useful parameter to optimize the performance of a microalgal photobioreactor and its scale-up. The aim of the present article is to discuss the experimental mass transfer features of this novel type of photobioreactor and highlight expected opportunities and issues entailed by different ways of installing and operating such novel types of photobioreactors.

scholarly journals Squalene Emulsion Manufacturing Process Scale-Up for Enhanced Global Pandemic Response

2020 ◽  
Vol 13 (8) ◽  
pp. 168
Author(s):  
Tony Phan ◽  
Christian Devine ◽  
Erik D. Laursen ◽  
Adrian Simpson ◽  
Aaron Kahn ◽  
...  
Keyword(s):  
Scale Up ◽  
Physicochemical Characteristics ◽  
Continuous Phase ◽  
Process Efficiency ◽  
Vaccine Antigen ◽  
Batch Size ◽  
Efficient Production ◽  
Viscosity Change ◽  
Charged Aerosol ◽  
Pandemic Response

Squalene emulsions are among the most widely employed vaccine adjuvant formulations. Among the demonstrated benefits of squalene emulsions is the ability to enable vaccine antigen dose sparing, an important consideration for pandemic response. In order to increase pandemic response capabilities, it is desirable to scale up adjuvant manufacturing processes. We describe innovative process enhancements that enabled the scale-up of bulk stable squalene emulsion (SE) manufacturing capacity from a 3000- to 5,000,000-dose batch size. Manufacture of concentrated bulk along with the accompanying viscosity change in the continuous phase resulted in a ≥25-fold process efficiency enhancement. Process streamlining and implementation of single-use biocontainers resulted in reduced space requirements, fewer unit operations, and minimization of cleaning requirements. Emulsion physicochemical characteristics were measured by dynamic light scattering, laser diffraction, and HPLC with charged aerosol detection. The newly developed full-scale process was demonstrated by producing two 5,000,000-dose batches of bulk concentrated SE. A scale-up of adjuvant manufacturing capacity through process innovation enables more efficient production capabilities for pandemic response.

scholarly journals Efficient production of myo-inositol in Escherichia coli through metabolic engineering

2020 ◽  
Author(s):  
Ran You ◽  
Lei Wang ◽  
Congrong Shi ◽  
Hao Chen ◽  
Shasha Zhang ◽  
...  
Keyword(s):  
Metabolic Engineering ◽  
Carbon Flux ◽  
Scale Up ◽  
Value Added ◽  
Efficient Production ◽  
Synthetic Pathway ◽  
E Coli ◽  
Mixed Carbon Source ◽  
Glycolysis Pathway

Abstract Background The biosynthesis of high value-added compounds through metabolically engineered strains has received widely attention in recent years. As an effective compound in pharmaceutical, cosmetic and food industry, myo-inositol (inositol) is mainly produced via a harsh set of chemical reactions from phytate. The proper distribution of carbon flux between cell growth and inositol production was a major challenge for constructing an efficient inositol-synthetic pathway. Recombinant E. coli strains have been constructed by metabolic engineering strategies to produce inositol, yet with a low yield. Therefore, construction of E. coli metabolically engineered strains with high stoichiometric yield will be attractive. Results In the present study, the recombinant E. coli strains with high stoichiometric yield (> 0.7 mol inositol/mol glucose) were obtained to efficiently synthesize inositol. Inositol was successfully biosynthesized after introducing two crucial enzymes, inositol-3-phosphate synthase (IPS) from Trypanosoma brucei , and inositol monophosphatase (IMP) from E. coli. Based on starting strains E. coli BW25113 (wild type) and SG104 ( ΔptsG::glk , ΔgalR::zglf , ΔpoxB::acs ), a series of engineered strains for inositol production were constructed by deleting the key genes pgi, pfkA or pykF . Furthermore, the plasmid expression systems of IPS and IMP were optimized, and the gene zwf was regulated to enhance stoichiometric yield. The highest stoichiometric yield (0.96 mol inositol/mol glucose) was achieved with the combined strain R15 of SG104, Δpgi , Δpgm , and RBSL5-zwf. Simultaneously, the engineered strain R04 reached high-density fermentation level in a 1-L fermenter by using glucose and glycerol as mixed carbon source. In the scale-up bioconversion in situ with R04, 0.82 mol inositol/mol glucose was produced by fed-batch within 23 h, corresponding to a titer of 106.3 g/L (590.5 mM). Conclusions The biosynthetic pathway of inositol from glucose in recombinant E. coli was optimized by metabolic engineering strategies. The metabolically engineered E. coli strains represent a promising method for future inositol production. This study provided an essential reference to obtain a suitable distribution of carbon flux between glycolysis pathway and product synthetic pathway.

scholarly journals Potential and Scale-Up of Pore-Through-Flow Membrane Reactors for the Production of Prebiotic Galacto-Oligosaccharides with Immobilized β-Galactosidase

Catalysts ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 7
Author(s):  
Ines Pottratz ◽  
Ines Müller ◽  
Christof Hamel
Keyword(s):  
Enzyme System ◽  
Scale Up ◽  
Optimal Operation ◽  
Free Enzyme ◽  
Membrane Reactors ◽  
Efficient Production ◽  
Batch Reactors ◽  
Operation Conditions ◽  
Through Flow ◽  
Space Time Yield

The production of prebiotics like galacto-oligosaccharides (GOS) on industrial scale is becoming more important due to increased demand. GOS are synthesized in batch reactors from bovine lactose using the cost intensive enzyme β-galactosidase (β-gal). Thus, the development of sustainable and more efficient production strategies, like enzyme immobilization in membrane reactors are a promising option. Activated methacrylatic monoliths were characterized as support for covalent immobilized β-gal to produce GOS. The macroporous monoliths act as immobilized pore-through-flow membrane reactors (PTFR) and reduce the influence of mass-transfer limitations by a dominating convective pore flow. Monolithic designs in the form of disks (0.34 mL) and for scale-up cylindric columns (1, 8 and 80 mL) in three different reactor operation configurations (semi-continuous, continuous and continuous with recirculation) were studied experimentally and compared to the free enzyme system. Kinetic data, immobilization efficiency, space-time-yield and long-term stability were determined for the immobilized enzyme. Furthermore, simulation studies were conducted to identify optimal operation conditions for further scale-up. Thus, the GOS yield could be increased by up to 60% in the immobilized PTFRs in semi-continuous operation compared to the free enzyme system. The enzyme activity and long-time stability was studied for more than nine months of intensive use.

scholarly journals Highly Efficient Production of Transfructosylating Enzymes Using Low-Cost Sugarcane Molasses by A. Pullulans FRR 5284

2021 ◽  
Author(s):  
Most Sheauly Khatun ◽  
Morteza Hassanpour ◽  
Mark Harrison ◽  
Robert Speight ◽  
Ian O'Hara ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Production Process ◽  
Enzyme Production ◽  
Low Cost ◽  
Scale Up ◽  
Extracellular Enzyme ◽  
Efficient Production ◽  
Sugarcane Molasses ◽  
Shake Flasks ◽  
Different Sources

Abstract In this study, sugarcane molasses was used to produce transfructosylating enzymes by A. pullulans FRR 5284. It was found that NaNO3 was a better nitrogen source than yeast extract while exogeneous phosphorous was not needed. Adding only 4.4 g/L NaNO3 into the molasses medium containing 100 g/L sugars led to the highest total transfructosylating activity of 123.8 U/mL. Scale-up of the enzyme production process from shake flasks to 1 L reactor improved the enzyme activity and productivity to 171.7 U/mL and 3.58 U/mL/h, 39% and 108% higher than the corresponding activity and productivity from shake flasks, respectively. FOS production from 500 g/L sucrose led to the highest yields of ~ 61% using intracellular, extracellular, and total enzymes from shake flasks and the reactor. Enzymes from different sources led to very different FOS profiles, indicating that FOS profiles can be controlled by adjusting intracellular and extracellular enzyme ratios to adjust prebiotic activity.

A Novel Reactor for Microwave Hydrothermal Scale-up Nanopowder Synthesis

2013 ◽  
Vol 11 (1) ◽  
pp. 361-368 ◽  
Author(s):  
Andrzej Majcher ◽  
Jan Wiejak ◽  
Jan Przybylski ◽  
Tadeusz Chudoba ◽  
Jacek Wojnarowicz
Keyword(s):  
Control System ◽  
Continuous Monitoring ◽  
Scale Up ◽  
Flow Mode ◽  
Efficient Production ◽  
Microwave Hydrothermal ◽  
Process Pressure ◽  
Verification Process ◽  
Stop Flow ◽  
Nanopowder Synthesis

Abstract The article presents a novel microwave reactor for hydrothermal synthesis of nanopowders. The reactor has a unique design of a process chamber, which, when used in conjunction with a batch control system, allows a highly efficient production of nanopowders. The design of the reactor together with the new principles of operation, structural materials and distribution of electromagnetic field are described. The article also presents a control system for the reactor, which allows for an automatic operation in the stop–flow mode, control of process pressure, continuous monitoring of process parameters and safe operation of the device. The device verification process is shown on the basis of the results of cobalt-doped zinc oxide nanopowder synthesis.

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