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Shangtian Yang - One of the best experts on this subject based on the ideXlab platform.
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effects of carbon dioxide on cell growth and Propionic Acid production from glycerol and glucose by propionibacterium AcidiPropionici
Bioresource Technology, 2015Co-Authors: An Zhang, Shangtian Yang, Zhongqiang Wang, Jianxin Sun, Haiying ZhouAbstract:The effects of CO2 on Propionic Acid production and cell growth in glycerol or glucose fermentation were investigated in this study. In glycerol fermentation, the volumetric productivity of Propionic Acid with CO2 supplementation reached 2.94g/L/day, compared to 1.56g/L/day without CO2. The cell growth using glycerol was also significantly enhanced with CO2. In addition, the yield and productivity of succinate, the main intermediate in Wood-Werkman cycle, increased 81% and 280%, respectively; consistent with the increased activities of pyruvate carboxylase and propionyl CoA transferase, two key enzymes in the Wood-Werkman cycle. However, in glucose fermentation CO2 had minimal effect on Propionic Acid production and cell growth. The carbon flux distributions using glycerol or glucose were also analyzed using a stoichiometric metabolic model. The calculated maintenance coefficient (mATP) increased 100%, which may explain the increase in the productivity of Propionic Acid in glycerol fermentation with CO2 supplement.
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Metabolic engineering of Propionibacterium freudenreichii: effect of expressing phosphoenolpyruvate carboxylase on Propionic Acid production
Applied Microbiology and Biotechnology, 2014Co-Authors: Ehab Mohamed Ammar, Ying Jin, Zhongqiang Wang, Shangtian YangAbstract:Propionic Acid is currently produced mainly via petrochemicals, but there is increasing interest in its fermentative production from renewable biomass. However, the current Propionic Acid fermentation process suffers from low product yield and productivity. In this work, the gene encoding phosphoenolpyruvate carboxylase (PPC) was cloned from Escherichia coli and expressed in Propionibacterium freudenreichii . PPC catalyzes the conversion of phosphoenolpyruvate to oxaloacetate with the fixation of one CO_2. Its expression in P. freudenreichii showed profound effects on Propionic Acid fermentation. Compared to the wild type, the mutant expressing the ppc gene grew significantly faster, consumed more glycerol, and produced propionate to a higher final titer at a faster rate. The mutant also produced significantly more propionate from glucose under elevated CO_2 partial pressure. These effects could be attributed to increased CO_2 fixation and resulting changes in the flux distributions in the dicarboxylic Acid pathway.
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Propionic Acid production in glycerol glucose co fermentation by propionibacterium freudenreichii subsp shermanii
Bioresource Technology, 2013Co-Authors: Zhongqiang Wang, Shangtian YangAbstract:Abstract Propionibacterium freudenreichii subsp. shermanii can ferment glucose and glycerol to Propionic Acid with acetic and succinic Acids as two by-products. Propionic Acid production from glucose was relatively fast (0.19 g/L h) but gave low product yield (∼0.39 g/g) and selectivity (P/A: ∼2.6; P/S: ∼4.8). In contrast, glycerol with a more reduced state gave a high Propionic Acid yield (∼0.65 g/g) and selectivity (P/A: ∼31; P/S: ∼11) but low productivity (0.11 g/L h). On the other hand, co-fermentation of glycerol and glucose at an appropriate mass ratio gave both a high yield (0.54–0.65 g/g) and productivity (0.18–0.23 g/L h) with high product selectivity (P/A: ∼14; P/S: ∼10). The carbon flux distributions in the co-fermentation as affected by the ratio of glycerol/glucose were investigated. Finally, co-fermentation with cassava bagasse hydrolysate and crude glycerol in a fibrous-bed bioreactor was demonstrated, providing an efficient way for economic production of bio-based Propionic Acid.
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enhanced Propionic Acid production from jerusalem artichoke hydrolysate by immobilized propionibacterium AcidiPropionici in a fibrous bed bioreactor
Bioprocess and Biosystems Engineering, 2012Co-Authors: Zexin Liang, Shangtian Yang, Youhua Cai, Jufang WangAbstract:Propionic Acid is an important chemical that is widely used in the food and chemical industries. To enhance Propionic Acid production, a fibrous-bed bioreactor (FBB) was constructed and Jerusalem artichoke hydrolysate was used as a low-cost renewable feedstock for immobilized fermentation. Comparison of the kinetics of immobilized-cell fermentation using the FBB with those of fed-batch free-cell fermentation showed that immobilized-cell fermentation gave a much higher Propionic Acid concentration (68.5 vs. 40.6 g/L), Propionic Acid yield (0.434 vs. 0.379 g/g) and Propionic Acid productivity (1.55 vs. 0.190 g/L/h) at pH 6.5. Furthermore, repeated batch fermentation, carried out to evaluate the stability of the FBB system, showed that long-term operation with a high average Propionic Acid yield of 0.483 g/g, high productivity of 3.69 g/L/h and Propionic Acid concentration of 26.2 g/L were achieved in all eight repeated batches during fermentation for more than 200 h. It is thus concluded that the FBB culture system can be utilized to realize the economical production of Propionic Acid from Jerusalem artichoke hydrolysate during long-term operation.
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Propionic Acid production from glycerol by metabolically engineered propionibacterium AcidiPropionici
Process Biochemistry, 2009Co-Authors: An Zhang, Shangtian YangAbstract:Abstract Large amounts of crude glycerol produced in the biodiesel industry can be used as a low-cost renewable feedstock to produce chemicals and fuels. Compared to sugars (sucrose, glucose, xylose, etc.), glycerol has a lower reducing level, which is of benefit to the production of reduced chemicals. In this work, glycerol as the sole carbon source in Propionic Acid fermentation by metabolically engineered Propionibacterium AcidiPropionici (ACK-Tet) was studied. It was found that the adapted ACK-Tet mutant could use glycerol for its growth and produced Propionic Acid at a high yield of 0.54–0.71 g/g, which was much higher than that from glucose (∼0.35 g/g). In addition, the production of acetic Acid in glycerol fermentation was much less than that from glucose. Thus, glycerol fermentation produced a high purity Propionic Acid with a high Propionic Acid to acetic Acid ratio of 22.4 (vs. ∼5 for glucose fermentation), facilitating the recovery and purification of Propionic Acid from the fermentation broth. The highest Propionic Acid concentration obtained from glycerol fermentation was ∼106 g/L, which was 2.5 times of the highest concentration (∼42 g/L) previously reported in the literature.
Rajni Hattikaul - One of the best experts on this subject based on the ideXlab platform.
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cell immobilization on 3d printed matrices a model study on Propionic Acid fermentation
Bioresource Technology, 2018Co-Authors: Fabricio Dos Santos Belgrano, Olaf Diegel, Nei Pereira, Rajni HattikaulAbstract:This study uses three-dimensional (3D) printing technology as a tool for designing carriers for immobilization of microbial cells for bioprocesses. Production of Propionic Acid from glucose by immobilized Propionibacterium sp. cells was studied as a model system. For cell adsorption, the 3D-printed nylon beads were added to the culture medium during 3 rounds of cell cultivation. Cell adsorption and fermentation kinetics were similar irrespective of the bead size and lattice structure. The cells bound to 15 mm beads exhibited reduced fermentation time as compared to free cell fermentations; maximum productivity and Propionic Acid titer of 0.46 g/L h and 25.8 g/L, respectively, were obtained. Treatment of the beads with polyethyleneimine improved cell-matrix binding, but lowered the productivity perhaps due to inhibitory effect of the polycation. Scanning electron micrographs revealed the cells to be located in crevices of the beads, but were more uniformly distributed on PEI-coated carrier indicating charge-charge interaction.
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improved Propionic Acid production from glycerol combining cyclic batch and sequential batch fermentations with optimal nutrient composition
Bioresource Technology, 2015Co-Authors: Tarek Dishisha, Maria Teresa Alvarez, Mohammad H A Ibrahim, Victor Hugo Cavero, Rajni HattikaulAbstract:Propionic Acid was produced from glycerol using Propionibacterium AcidiPropionici. In this study, the impact of the concentrations of carbon and nitrogen sources, and of different modes of high cell density fermentations on process kinetics and -efficiency was investigated. Three-way ANOVA analysis and batch cultivations at varying C/N ratios at pH 6.5 revealed that Propionic Acid production rate is significantly influenced by yeast extract concentration. Glycerol to yeast extract ratio (w w−1) of 3:1 was required for complete glycerol consumption, while maintaining the volumetric productivity. Using this optimum C/N ratio for Propionic Acid production in cyclic batch fermentation gave propionate yield up to 93 mol% and productivity of 0.53 g L−1 h−1. Moreover, sequential batch fermentation with cell recycling resulted in production rates exceeding 1 g L−1 h−1 at initial glycerol up to 120 g L−1, and a maximum of 1.63 g L−1 h−1 from 90 g L−1 glycerol.
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batch and continuous Propionic Acid production from glycerol using free and immobilized cells of propionibacterium AcidiPropionici
Bioresource Technology, 2012Co-Authors: Tarek Dishisha, Maria Teresa Alvarez, Rajni HattikaulAbstract:Propionic Acid production from glycerol was studied using Propionibacterium AcidiPropionici DSM 4900 cells immobilized on polyethylenimine-treated Poraver (PEI-Poraver) and Luffa (PEI-Luffa), respectively. Using PEI-Luffa, the average productivity, yield and concentration of Propionic Acid from 40 g L(-1) glycerol were 0.29 g L(-1) h(-1), 0.74 mol(PA) mol(Gly)(-1) and 20 g L(-1), respectively, after four consecutive recycle-batches. PEI-Poraver supported attachment of 31 times higher amounts of cells than PEI-Luffa and produced 20, 28 and 35 g L(-1) Propionic Acid from 40, 65 and 85 g L(-1) glycerol, respectively (0.61 mol(PA) mol(Gly)(-1)). The corresponding production rates were 0.86, 0.43 and 0.35 g L(-1) h(-1), which are the highest reported from glycerol via batch or fed-batch fermentations for equivalent Propionic Acid concentrations. Using a continuous mode of operation at a dilution rate of 0.1 h(-1), cell washout was observed in the bioreactor with free cells; however, Propionic Acid productivity, yield and concentration were 1.40 g L(-1) h(-1), 0.86 mol(PA) mol(Gly)(-1), and 15 g L(-1), respectively, using immobilized cells in the PEI-Poraver bioreactor. The choice of the immobilization matrix can thus significantly influence the fermentation efficiency and profile. The bioreactor using cells immobilized on PEI-Poraver allowed the fermentation of higher glycerol concentrations and provided stable and higher fermentation rates than that using free cells or the cells immobilized on PEI-Luffa.
Tarek Dishisha - One of the best experts on this subject based on the ideXlab platform.
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improved Propionic Acid production from glycerol combining cyclic batch and sequential batch fermentations with optimal nutrient composition
Bioresource Technology, 2015Co-Authors: Tarek Dishisha, Maria Teresa Alvarez, Mohammad H A Ibrahim, Victor Hugo Cavero, Rajni HattikaulAbstract:Propionic Acid was produced from glycerol using Propionibacterium AcidiPropionici. In this study, the impact of the concentrations of carbon and nitrogen sources, and of different modes of high cell density fermentations on process kinetics and -efficiency was investigated. Three-way ANOVA analysis and batch cultivations at varying C/N ratios at pH 6.5 revealed that Propionic Acid production rate is significantly influenced by yeast extract concentration. Glycerol to yeast extract ratio (w w−1) of 3:1 was required for complete glycerol consumption, while maintaining the volumetric productivity. Using this optimum C/N ratio for Propionic Acid production in cyclic batch fermentation gave propionate yield up to 93 mol% and productivity of 0.53 g L−1 h−1. Moreover, sequential batch fermentation with cell recycling resulted in production rates exceeding 1 g L−1 h−1 at initial glycerol up to 120 g L−1, and a maximum of 1.63 g L−1 h−1 from 90 g L−1 glycerol.
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An economical biorefinery process for Propionic Acid production from glycerol and potato juice using high cell density fermentation.
Bioresource technology, 2012Co-Authors: Tarek Dishisha, Åke Ståhl, Stefan Lundmark, Rajni Hatti-kaulAbstract:An economically sustainable process was developed for Propionic Acid production by fermentation of glycerol using Propionibacterium AcidiPropionici and potato juice, a by-product of starch processing, as a nitrogen/vitamin source. The fermentation was done as high-cell-density sequential batches with cell recycle. Propionic Acid production and glycerol consumption rates were dependent on initial biomass concentration, and reached a maximum of 1.42 and 2.30gL(-1)h(-1), respectively, from 50gL(-1) glycerol at initial cell density of 23.7g(CDW)L(-1). Halving the concentration of nitrogen/vitamin source resulted in reduction of acetic and succinic Acids yields by ∼39% each. At glycerol concentrations of 85 and 120gL(-1), respectively, 43.8 and 50.8gL(-1) Propionic Acid were obtained at a rate of 0.88 and 0.29gL(-1)h(-1) and yield of 84 and 78mol%. Succinic Acid was 13g% of Propionic Acid and could represent a potential co-product covering the cost of nitrogen/vitamin source. (Less)
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batch and continuous Propionic Acid production from glycerol using free and immobilized cells of propionibacterium AcidiPropionici
Bioresource Technology, 2012Co-Authors: Tarek Dishisha, Maria Teresa Alvarez, Rajni HattikaulAbstract:Propionic Acid production from glycerol was studied using Propionibacterium AcidiPropionici DSM 4900 cells immobilized on polyethylenimine-treated Poraver (PEI-Poraver) and Luffa (PEI-Luffa), respectively. Using PEI-Luffa, the average productivity, yield and concentration of Propionic Acid from 40 g L(-1) glycerol were 0.29 g L(-1) h(-1), 0.74 mol(PA) mol(Gly)(-1) and 20 g L(-1), respectively, after four consecutive recycle-batches. PEI-Poraver supported attachment of 31 times higher amounts of cells than PEI-Luffa and produced 20, 28 and 35 g L(-1) Propionic Acid from 40, 65 and 85 g L(-1) glycerol, respectively (0.61 mol(PA) mol(Gly)(-1)). The corresponding production rates were 0.86, 0.43 and 0.35 g L(-1) h(-1), which are the highest reported from glycerol via batch or fed-batch fermentations for equivalent Propionic Acid concentrations. Using a continuous mode of operation at a dilution rate of 0.1 h(-1), cell washout was observed in the bioreactor with free cells; however, Propionic Acid productivity, yield and concentration were 1.40 g L(-1) h(-1), 0.86 mol(PA) mol(Gly)(-1), and 15 g L(-1), respectively, using immobilized cells in the PEI-Poraver bioreactor. The choice of the immobilization matrix can thus significantly influence the fermentation efficiency and profile. The bioreactor using cells immobilized on PEI-Poraver allowed the fermentation of higher glycerol concentrations and provided stable and higher fermentation rates than that using free cells or the cells immobilized on PEI-Luffa.
An Zhang - One of the best experts on this subject based on the ideXlab platform.
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effects of carbon dioxide on cell growth and Propionic Acid production from glycerol and glucose by propionibacterium AcidiPropionici
Bioresource Technology, 2015Co-Authors: An Zhang, Shangtian Yang, Zhongqiang Wang, Jianxin Sun, Haiying ZhouAbstract:The effects of CO2 on Propionic Acid production and cell growth in glycerol or glucose fermentation were investigated in this study. In glycerol fermentation, the volumetric productivity of Propionic Acid with CO2 supplementation reached 2.94g/L/day, compared to 1.56g/L/day without CO2. The cell growth using glycerol was also significantly enhanced with CO2. In addition, the yield and productivity of succinate, the main intermediate in Wood-Werkman cycle, increased 81% and 280%, respectively; consistent with the increased activities of pyruvate carboxylase and propionyl CoA transferase, two key enzymes in the Wood-Werkman cycle. However, in glucose fermentation CO2 had minimal effect on Propionic Acid production and cell growth. The carbon flux distributions using glycerol or glucose were also analyzed using a stoichiometric metabolic model. The calculated maintenance coefficient (mATP) increased 100%, which may explain the increase in the productivity of Propionic Acid in glycerol fermentation with CO2 supplement.
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Propionic Acid production from glycerol by metabolically engineered propionibacterium AcidiPropionici
Process Biochemistry, 2009Co-Authors: An Zhang, Shangtian YangAbstract:Abstract Large amounts of crude glycerol produced in the biodiesel industry can be used as a low-cost renewable feedstock to produce chemicals and fuels. Compared to sugars (sucrose, glucose, xylose, etc.), glycerol has a lower reducing level, which is of benefit to the production of reduced chemicals. In this work, glycerol as the sole carbon source in Propionic Acid fermentation by metabolically engineered Propionibacterium AcidiPropionici (ACK-Tet) was studied. It was found that the adapted ACK-Tet mutant could use glycerol for its growth and produced Propionic Acid at a high yield of 0.54–0.71 g/g, which was much higher than that from glucose (∼0.35 g/g). In addition, the production of acetic Acid in glycerol fermentation was much less than that from glucose. Thus, glycerol fermentation produced a high purity Propionic Acid with a high Propionic Acid to acetic Acid ratio of 22.4 (vs. ∼5 for glucose fermentation), facilitating the recovery and purification of Propionic Acid from the fermentation broth. The highest Propionic Acid concentration obtained from glycerol fermentation was ∼106 g/L, which was 2.5 times of the highest concentration (∼42 g/L) previously reported in the literature.
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engineering propionibacterium AcidiPropionici for enhanced Propionic Acid tolerance and fermentation
Biotechnology and Bioengineering, 2009Co-Authors: An Zhang, Shangtian YangAbstract:Propionibacterium AcidiPropionici, a Gram-positive, anaerobic bacterium, has been the most used species for Propionic Acid production from sugars. In this study, the metabolically engineered mutant ACK-Tet, which has its acetate kinase gene knocked out from the chromosome, was immobilized and adapted in a fibrous bed bioreactor (FBB) to increase its Acid tolerance and ability to produce Propionic Acid at a high final concentration in fed-batch fermentation. After about 3 months adaptation in the FBB, the Propionic Acid concentration in the fermentation broth reached approximately 100 g/L, which was much higher than the highest concentration of approximately 71 g/L previously attained with the wild-type in the FBB. To understand the mechanism and factors contributing to the enhanced Acid tolerance, adapted mutant cells were harvested from the FBB and characterized for their morphology, growth inhibition by Propionic Acid, protein expression profiles as observed in SDS-PAGE, and H+-ATPase activity, which is related to the proton pumping and cell's ability to control its intracellular pH gradient. The adapted mutant obtained from the FBB showed significantly reduced growth sensitivity to Propionic Acid inhibition, increased H+-ATPase expression and activity, and significantly elongated rod morphology.
Mehmet Bilgin - One of the best experts on this subject based on the ideXlab platform.
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Separation of Propionic Acid by diethyl carbonate or diethyl malonate or diethyl fumarate and the synergistic effect of phosphorus compounds and amines
Fluid Phase Equilibria, 2010Co-Authors: Mehmet Bilgin, İmge BirmanAbstract:Abstract The recovery of Propionic Acid from aqueous solutions such as fermentation broth and wastewater is an important problem where liquid extraction is the favorite process. Liquid–liquid equilibrium (LLE) data were investigated for mixtures of water + Propionic Acid + diethyl carbonate or diethyl malonate or diethyl fumarate at 298.15 K. The solubility curves and the tie-line end compositions of liquid phases at equilibrium were determined experimentally, and the tie-line results compared with the data correlated by means of UNIQUAC model. The phase diagrams for the ternary mixtures including both the experimental and correlated tie-lines are presented. The reliability of the experimental tie-lines was confirmed by using Othmer–Tobias correlation. The distribution coefficients and the separation factors for the immiscibility region are calculated. In order to boost the distribution of Propionic Acid between aqueous and organic phases, the distribution was investigated by using organic solutions composed of amine {tributylamine (TBA)} and phosphorus containing compounds {trioctylphosphine oxide (TOPO) or tributyl phosphate (TBP)} dissolved in diethyl carbonate, diethyl malonate and diethyl fumarate, in the concentration range of about 0.06–1.00 mol/l. It was observed that the used solvents may serve individually as adequate agents to extract Propionic Acid from its dilute aqueous solution; however, the extraction performance can be improved by using phosphorus containing compounds or amines, mostly by using tributylamine dissolved in diethylmalonate.
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quaternary liquid liquid equilibrium of water acetic Acid Propionic Acid solvent amyl alcohol cyclohexyl acetate or toluene systems
Journal of Chemical & Engineering Data, 2004Co-Authors: Süheyla Çehreli, Mehmet BilginAbstract:Liquid−liquid equilibrium data of water + acetic Acid + Propionic Acid + solvent (amyl alcohol, cyclohexyl acetate, and toluene) quaternary systems were determined. Solubility curves and tie lines were measured at 298.15 K. A comparison of the extracting capabilities of the solvents was made with respect to distribution coefficients, separation factors, and solvent-free selectivity bases. The reliability of the data was ascertained from Othmer−Tobias plots. We conclude that all solvents are suitable separating agents for dilute aqueous acetic and Propionic Acid mixtures.
