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R W Hutkins - One of the best experts on this subject based on the ideXlab platform.
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acetone butanol ethanol abe recovery by pervaporation using silicalite silicone composite membrane from Fed Batch Reactor of clostridium acetobutylicum
Journal of Membrane Science, 2001Co-Authors: N Qureshi, Michael M Meaghe, Jicai Huang, R W HutkinsAbstract:Abstract Acetone butanol ethanol (ABE) were produced in an integrated fermentation-product recovery system using Clostridium acetobutylicum ( C. acetobutylicum ) and a silicalite–silicone composite membrane. Cells of C. acetobutylicum were removed from the cell culture using a 500,000 molecular weight cut-off ultrafiltration membrane and returned to the Fed-Batch fermentor. The ABE was removed from the ultrafiltration permeate using a silicalite–silicone composite pervaporation membrane. The silicalite–silicone composite membrane (306 μm thick) was made in our laboratory and characterized for flux and selectivities using model acetone ethanol butanol solution. Flux of the silicalite–silicone composite membrane was constant during pervaporation of fermentation broth at the same concentration of ABE. Acetone butanol selectivity was also not affected by the fermentation broth, indicating that the membrane was not fouled by the ABE fermentation broth. The silicalite–silicone composite membrane was exposed to fermentation broth for 120 h. Acetic acid and ethanol did not diffuse through the silicalite–silicone composite membrane at low concentrations. The Fed-Batch Reactor was operated for 870 h. Totally 154.97 g/l solvents was produced at solvent yield of 0.31–0.35.
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Acetone butanol ethanol (ABE) recovery by pervaporation using silicalite–silicone composite membrane from Fed-Batch Reactor of Clostridium acetobutylicum
Journal of Membrane Science, 2001Co-Authors: N Qureshi, Jicai Huang, Michael M. Meagher, R W HutkinsAbstract:Abstract Acetone butanol ethanol (ABE) were produced in an integrated fermentation-product recovery system using Clostridium acetobutylicum ( C. acetobutylicum ) and a silicalite–silicone composite membrane. Cells of C. acetobutylicum were removed from the cell culture using a 500,000 molecular weight cut-off ultrafiltration membrane and returned to the Fed-Batch fermentor. The ABE was removed from the ultrafiltration permeate using a silicalite–silicone composite pervaporation membrane. The silicalite–silicone composite membrane (306 μm thick) was made in our laboratory and characterized for flux and selectivities using model acetone ethanol butanol solution. Flux of the silicalite–silicone composite membrane was constant during pervaporation of fermentation broth at the same concentration of ABE. Acetone butanol selectivity was also not affected by the fermentation broth, indicating that the membrane was not fouled by the ABE fermentation broth. The silicalite–silicone composite membrane was exposed to fermentation broth for 120 h. Acetic acid and ethanol did not diffuse through the silicalite–silicone composite membrane at low concentrations. The Fed-Batch Reactor was operated for 870 h. Totally 154.97 g/l solvents was produced at solvent yield of 0.31–0.35.
N Qureshi - One of the best experts on this subject based on the ideXlab platform.
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High solid Fed‐Batch butanol fermentation with simultaneous product recovery: Part II—process integration
Biotechnology progress, 2018Co-Authors: N Qureshi, Badal C. Saha, K. Thomas Klasson, Siqing LiuAbstract:In these studies, liquid hot water (LHW) pretreated and enzymatically hydrolyzed Sweet Sorghum Bagasse (SSB) hydrolyzates were fermented in a Fed-Batch Reactor. As reported in the preceding paper, the culture was not able to ferment the hydrolyzate I in a Batch process due to presence of high level of toxic chemicals, in particular acetic acid released from SSB during the hydrolytic process. To be able to ferment the hydrolyzate I obtained from 250 g L-1 SSB hydrolysis, a Fed-Batch Reactor with in situ butanol recovery was devised. The process was started with the hydrolyzate II and when good cell growth and vigorous fermentation were observed, the hydrolyzate I was slowly Fed to the Reactor. In this manner the culture was able to ferment all the sugars present in both the hydrolyzates to acetone butanol ethanol (ABE). In a control Batch Reactor in which ABE was produced from glucose, ABE productivity and yield of 0.42 g L-1 h-1 and 0.36 were obtained, respectively. In the Fed-Batch Reactor Fed with SSB hydrolyzates, these productivity and yield values were 0.44 g L-1 h-1 and 0.45, respectively. ABE yield in the integrated system was high due to utilization of acetic acid to convert to ABE. In summary we were able to utilize both the hydrolyzates obtained from LHW pretreated and enzymatically hydrolyzed SSB (250 g L-1 ) and convert them to ABE. Complete fermentation was possible due to simultaneous recovery of ABE by vacuum. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:967-972, 2018.
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acetone butanol ethanol abe recovery by pervaporation using silicalite silicone composite membrane from Fed Batch Reactor of clostridium acetobutylicum
Journal of Membrane Science, 2001Co-Authors: N Qureshi, Michael M Meaghe, Jicai Huang, R W HutkinsAbstract:Abstract Acetone butanol ethanol (ABE) were produced in an integrated fermentation-product recovery system using Clostridium acetobutylicum ( C. acetobutylicum ) and a silicalite–silicone composite membrane. Cells of C. acetobutylicum were removed from the cell culture using a 500,000 molecular weight cut-off ultrafiltration membrane and returned to the Fed-Batch fermentor. The ABE was removed from the ultrafiltration permeate using a silicalite–silicone composite pervaporation membrane. The silicalite–silicone composite membrane (306 μm thick) was made in our laboratory and characterized for flux and selectivities using model acetone ethanol butanol solution. Flux of the silicalite–silicone composite membrane was constant during pervaporation of fermentation broth at the same concentration of ABE. Acetone butanol selectivity was also not affected by the fermentation broth, indicating that the membrane was not fouled by the ABE fermentation broth. The silicalite–silicone composite membrane was exposed to fermentation broth for 120 h. Acetic acid and ethanol did not diffuse through the silicalite–silicone composite membrane at low concentrations. The Fed-Batch Reactor was operated for 870 h. Totally 154.97 g/l solvents was produced at solvent yield of 0.31–0.35.
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Acetone butanol ethanol (ABE) recovery by pervaporation using silicalite–silicone composite membrane from Fed-Batch Reactor of Clostridium acetobutylicum
Journal of Membrane Science, 2001Co-Authors: N Qureshi, Jicai Huang, Michael M. Meagher, R W HutkinsAbstract:Abstract Acetone butanol ethanol (ABE) were produced in an integrated fermentation-product recovery system using Clostridium acetobutylicum ( C. acetobutylicum ) and a silicalite–silicone composite membrane. Cells of C. acetobutylicum were removed from the cell culture using a 500,000 molecular weight cut-off ultrafiltration membrane and returned to the Fed-Batch fermentor. The ABE was removed from the ultrafiltration permeate using a silicalite–silicone composite pervaporation membrane. The silicalite–silicone composite membrane (306 μm thick) was made in our laboratory and characterized for flux and selectivities using model acetone ethanol butanol solution. Flux of the silicalite–silicone composite membrane was constant during pervaporation of fermentation broth at the same concentration of ABE. Acetone butanol selectivity was also not affected by the fermentation broth, indicating that the membrane was not fouled by the ABE fermentation broth. The silicalite–silicone composite membrane was exposed to fermentation broth for 120 h. Acetic acid and ethanol did not diffuse through the silicalite–silicone composite membrane at low concentrations. The Fed-Batch Reactor was operated for 870 h. Totally 154.97 g/l solvents was produced at solvent yield of 0.31–0.35.
Jicai Huang - One of the best experts on this subject based on the ideXlab platform.
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acetone butanol ethanol abe recovery by pervaporation using silicalite silicone composite membrane from Fed Batch Reactor of clostridium acetobutylicum
Journal of Membrane Science, 2001Co-Authors: N Qureshi, Michael M Meaghe, Jicai Huang, R W HutkinsAbstract:Abstract Acetone butanol ethanol (ABE) were produced in an integrated fermentation-product recovery system using Clostridium acetobutylicum ( C. acetobutylicum ) and a silicalite–silicone composite membrane. Cells of C. acetobutylicum were removed from the cell culture using a 500,000 molecular weight cut-off ultrafiltration membrane and returned to the Fed-Batch fermentor. The ABE was removed from the ultrafiltration permeate using a silicalite–silicone composite pervaporation membrane. The silicalite–silicone composite membrane (306 μm thick) was made in our laboratory and characterized for flux and selectivities using model acetone ethanol butanol solution. Flux of the silicalite–silicone composite membrane was constant during pervaporation of fermentation broth at the same concentration of ABE. Acetone butanol selectivity was also not affected by the fermentation broth, indicating that the membrane was not fouled by the ABE fermentation broth. The silicalite–silicone composite membrane was exposed to fermentation broth for 120 h. Acetic acid and ethanol did not diffuse through the silicalite–silicone composite membrane at low concentrations. The Fed-Batch Reactor was operated for 870 h. Totally 154.97 g/l solvents was produced at solvent yield of 0.31–0.35.
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Acetone butanol ethanol (ABE) recovery by pervaporation using silicalite–silicone composite membrane from Fed-Batch Reactor of Clostridium acetobutylicum
Journal of Membrane Science, 2001Co-Authors: N Qureshi, Jicai Huang, Michael M. Meagher, R W HutkinsAbstract:Abstract Acetone butanol ethanol (ABE) were produced in an integrated fermentation-product recovery system using Clostridium acetobutylicum ( C. acetobutylicum ) and a silicalite–silicone composite membrane. Cells of C. acetobutylicum were removed from the cell culture using a 500,000 molecular weight cut-off ultrafiltration membrane and returned to the Fed-Batch fermentor. The ABE was removed from the ultrafiltration permeate using a silicalite–silicone composite pervaporation membrane. The silicalite–silicone composite membrane (306 μm thick) was made in our laboratory and characterized for flux and selectivities using model acetone ethanol butanol solution. Flux of the silicalite–silicone composite membrane was constant during pervaporation of fermentation broth at the same concentration of ABE. Acetone butanol selectivity was also not affected by the fermentation broth, indicating that the membrane was not fouled by the ABE fermentation broth. The silicalite–silicone composite membrane was exposed to fermentation broth for 120 h. Acetic acid and ethanol did not diffuse through the silicalite–silicone composite membrane at low concentrations. The Fed-Batch Reactor was operated for 870 h. Totally 154.97 g/l solvents was produced at solvent yield of 0.31–0.35.
Palma Parascandola - One of the best experts on this subject based on the ideXlab platform.
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Production in Fed-Batch Reactor of Bacillus subtilis LipaseA Immobilized on its own Producer Saccharomyces cerevisiae Cells
Chemical engineering transactions, 2013Co-Authors: Lucia Paciello, Carmine Landi, Jesús Zueco, Palma ParascandolaAbstract:Lipases (EC 3.1.1.3, triacylglycerol hydrolases), a subclass of the esterases (EC 3.1.1.1, carboxyl ester hydrolases) are one of the most important groups of biocatalysts for biotechnological uses such as synthesis of biopolymers and biodiesel, production of enantiopure pharmaceuticals, detergent formulation or the production of flavour compounds. Lipases can be commercialized as free or immobilized form. Nowadays it is of great interest to obtain immobilized enzymes especially for industrial applications since immobilization confers stability giving the possibility to recover the biocatalyst after its use, simplifying downstream processing. In the present work, Lipase A from Bacillus subtilis has been expressed in different strains of the yeast S. cerevisiae as a fusion protein with the yeast cell-wall mannoprotein Pir4. The corresponding gene fusion was created by inserting all the coding sequence of the lipase A gene in the BglII restriction site of PIR4 gene, leading to the expression of a fusion protein still containing the four cysteine residues responsible for the anchorage of Pir4 to the yeast cell wall.Production of lipase as a naturally immobilized biocatalyst was carried out allowing yeast cells to proliferate in a Fed-Batch Reactor under glucose limitation to promote a fully respiratory metabolism and consequently high biomass yield. The performance of the producer strains was evaluated in terms of cell density and enzyme productivity. A preliminary study of economic feasibility of a single fermentation run has been performed based on the experimental results obtained.
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Mathematical Modeling as a Tool to Describe and Optimize Heterologous Protein Production by Yeast Cells in Aerated Fed-Batch Reactor
Chemical engineering transactions, 2012Co-Authors: Lucia Paciello, Carmine Landi, Elisabetta De Alteriis, Palma ParascandolaAbstract:In this work, two recombinant yeast strains, the prototrophic non-conventional Zygosaccharomyces bailii [pZ3KlIL-1s] and the auxotrophic Saccharomyces cerevisiae BY4741[PIR4-IL1s], both producing human interleukin-1s, have been cultured in aerated Fed-Batch using glucose as limiting substrate. A mathematical model of the Fed-Batch Reactor has been developed, based on mass balance equations of the main process variables -biomass, glucose and product- and implemented with kinetic expressions to explain the yeast behaviour within the aerated Fed-Batch Reactor. In the case of Z. bailii, the mathematical model evidenced the suitability of the fermentative inoculum with respect to the respiratory one at the start of the exponential feeding. In the case of the auxotrophic S. cerevisiae BY4741, the modellistic approach has permitted to highlight a strong deviation from the expected behaviour and quantify the glucose amount that is spent for maintenance rather than for growth, thus impairing the outcome of the bioprocess.
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Effect of auxotrophies on yeast performance in aerated Fed-Batch Reactor
Biochemical and biophysical research communications, 2011Co-Authors: Carmine Landi, Lucia Paciello, Elisabetta De Alteriis, Luca Brambilla, Palma ParascandolaAbstract:A systematic investigation on the effects of auxotrophies on the performance of yeast in aerated Fed-Batch Reactor was carried out. Six isogenic strains from the CEN.PK family of Saccharomyces cerevisiae, one prototroph and five auxotrophs, were grown in aerated Fed-Batch Reactor using the same operative conditions and a proper nutritional supplementation. The performance of the strains, in terms of final biomass decreased with increasing the number of auxotrophies. Auxotrophy for leucine exerted a profound negative effect on the performance of the strains. Accumulation of reactive oxygen species (ROS) in the cells of the strain carrying four auxotrophies and its significant viability loss, were indicative of an oxidative stress response induced by exposure of cells to the environmental conditions. The mathematical model was fundamental to highlight how the carbon flux, depending on the number and type of auxotrophies, was diverted towards the production of increasingly large quantities of energy for maintenance.
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Expression of human interleukin-1β in Saccharomyces cerevisiae using PIR4 as fusion partner and production in aerated Fed-Batch Reactor.
Annals of Microbiology, 2010Co-Authors: Lucia Paciello, Elisabetta De Alteriis, Jesús Zueco, Isabel Andrés, Michele M. Bianchi, Palma ParascandolaAbstract:To circumvent cell wall retention commonly associated to Saccharomyces cerevisiae when used as a host for heterologous protein production, we have created a translational fusion of human interleukin-1β (IL-1β) to the Pir4 cell wall protein, so as to drive the secretion of the recombinant product to the growth medium. The auxotrophic S. cerevisiae BY4741 was used as host to express the Pir4-IL1β fusion protein. Once it was ascertained that the fusion protein was secreted to the culture medium and behaved as a growth-linked product, S. cerevisiae BY4741 [PIR4-IL1β] was cultured in an aerated Fed-Batch Reactor to achieve high cell density and, consequently, high product concentration in the medium. Two cultivation media were employed, a rich complex and a defined mineral medium, the latter suitably supplemented with bacto-casamino acids as ACA (auxotrophy-complementing amino acid) source. The rich complex medium allowed a good performance of the producer strain only during Batch growth, but was revealed to be inadequate for long-term Fed-Batch operations. The defined mineral medium ensured a better performance, even though not yet satisfactory in spite of a proper ACA supplementation. The behaviour of BY4741 was attributed to an intrinsic sensitivity of the producer strain to long-term aerated Fed-Batch operations.
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Effect of auxotrophies on yeast growth in aerated Fed-Batch Reactor
Journal of Biotechnology, 2010Co-Authors: Lucia Paciello, Carmine Landi, Elisabetta De Alteriis, Luca Brambilla, Palma ParascandolaAbstract:Mutant and deletion strains of the yeast Saccharomyces cerevisiae\ud having one/several auxotrophies are largely used in the\ud development of recombinant strains for heterologous protein\ud production because they ensure maintenance of plasmids with\ud selectable markers. The production is usually carried out by culturing the recombinant strain in aerated Fed-Batch, where sugar\ud limitation achieves high yields of biomass and product.\ud In a previous work, it was evidenced that growth of the auxotrophic S. cerevisiae BY4741 (MATa, ura30, leu20, met150,\ud his31) engineered for human IL-1 production, and employed\ud in aerated Fed-Batch, early arrested even in the presence of a\ud correct nutritional complementation (being specific nutrients for\ud genetically uncomplemented auxotrophies provided in no growthlimiting amounts). It was assumed that this behaviour may depend on the high number of auxotrophies, since the prototrophic S288C, from which BY4741 derives, showed a typical performance under the same cultivation mode. Therefore, a systematic investigation on the effect of auxotrophies on yeast growth in aerated Fed-Batch was carried out. Four isogenic strains of the CEN.PK family, with a progressively increasing number of auxotrophies (from one to four) were assayed under Fed-Batch conditions and a proper nutritional complementation. Feeding to the Reactor was exponentially increased imposing a specific growth rate below the critical one. The behaviour of the auxotrophic strains was compared with that of the isogenic prototrophic strain. by evaluating the capacity to keep the specific growth rate chosen. A clear correlation among optimum growth and number of auxotrophies has been found. Furthermore we have investigated the possible effect of the type of auxotrophy (ura- or leu-) on the strain performance, monitoring as well cell viability of each strain. The study is a contribution to know the phenotypic effects of auxotrophies in yeast and can have implications for biotechnological applications
Michael M. Meagher - One of the best experts on this subject based on the ideXlab platform.
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Acetone butanol ethanol (ABE) recovery by pervaporation using silicalite–silicone composite membrane from Fed-Batch Reactor of Clostridium acetobutylicum
Journal of Membrane Science, 2001Co-Authors: N Qureshi, Jicai Huang, Michael M. Meagher, R W HutkinsAbstract:Abstract Acetone butanol ethanol (ABE) were produced in an integrated fermentation-product recovery system using Clostridium acetobutylicum ( C. acetobutylicum ) and a silicalite–silicone composite membrane. Cells of C. acetobutylicum were removed from the cell culture using a 500,000 molecular weight cut-off ultrafiltration membrane and returned to the Fed-Batch fermentor. The ABE was removed from the ultrafiltration permeate using a silicalite–silicone composite pervaporation membrane. The silicalite–silicone composite membrane (306 μm thick) was made in our laboratory and characterized for flux and selectivities using model acetone ethanol butanol solution. Flux of the silicalite–silicone composite membrane was constant during pervaporation of fermentation broth at the same concentration of ABE. Acetone butanol selectivity was also not affected by the fermentation broth, indicating that the membrane was not fouled by the ABE fermentation broth. The silicalite–silicone composite membrane was exposed to fermentation broth for 120 h. Acetic acid and ethanol did not diffuse through the silicalite–silicone composite membrane at low concentrations. The Fed-Batch Reactor was operated for 870 h. Totally 154.97 g/l solvents was produced at solvent yield of 0.31–0.35.