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Mainul Hassan - One of the best experts on this subject based on the ideXlab platform.
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influence of nitrogen and iron limitations on lipid production by cryptococcus curvatus grown in Batch and fed Batch Culture
Process Biochemistry, 1996Co-Authors: Mainul Hassan, P J Blanc, Louismarie Granger, Alain Pareilleux, Gérard GomaAbstract:Abstract Cryptococcus curvatus , an oleaginous yeast, was grown under iron (Fe) and nitrogen (N)-limited conditions to produce lipid with a high stearic acid (C18:0) content in Batch and fed-Batch Culture. In Batch Culture, lack of ferrous ions had no evident effect on growth, lipid production or lipid composition. The highest stearic acid content in the total lipid was 14% in N-limited medium in Batch Culture. The combined effect of Fe and N-limitation in fed-Batch Culture was to increase the stearic acid content to 19% of the total lipids and the consumed carbon to nitrogen (C:N) ratio to 20 g/g. The highest biomass concentration achieved was 70 g/litre and 53% (w/w) lipid accumulated when grown for about 172 h in fed-Batch Culture. A C:N ratio between 20 and 50 was optimal for intracellular lipid accumulation and a ratio > 50 g/g became crucial for both growth and lipid production in fed-Batch Culture. The maximal C:N ratio achieved at the end of the Culture was 75 g/g. Lipid yield from glucose (g lipid/g glucose) was 0·14 and the fatty acids of lipids obtained were mainly oleic (C18:1), palmitic (C16:0) and stearic (C18:0).
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production of cocoa butter equivalents from prickly pear juice fermentation by an unsaturated fatty acid auxotroph of cryptococcus curvatus grown in Batch Culture
Process Biochemistry, 1995Co-Authors: Mainul Hassan, P J Blanc, Alain Pareilleux, Gérard GomaAbstract:An unsaturated fatty acid auxotroph derived from the oleaginous yeast Cryptococcus curvatus and named UfaM3 was defective in the conversion of stearic to oleic acid. It was cultivated on diluted (25%) prickly-pear juice in Batch Culture. The carbon to nitrogen ratio (C:N ratio) of the juice (44% glucose and 56% fructose content) was about 50 g/g. Differential utilization of glucose and fructose was observed. The efficiency of substrate conversion was 0·50 g/g for biomass and 0·21 g/g for lipids. The quality of lipids produced by UfaM3 approached cocoa butter.
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production of single cell oil from prickly pear juice fermentation by cryptococcus curvatus grown in Batch Culture
World Journal of Microbiology & Biotechnology, 1994Co-Authors: Mainul Hassan, P J Blanc, Alain Pareilleux, Gérard GomaAbstract:The biomass of Cryptococcus curvatus, an oleaginous yeast, reached 11 g/l and accumulated 46% (w/w) lipid when grown for 35 h in Batch Culture on diluted (25%) prickly-pear juice. The C:N ratio of the juice was about 50 g/g. The efficiency of substrate conversion was 0.48 g/g for biomass and 0.22 g/g for lipids. The extracted lipids were mainly oleic (18:1) and palmitic (16:0) acids and the quality of pipid approached that of palm oil.
Gérard Goma - One of the best experts on this subject based on the ideXlab platform.
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influence of nitrogen and iron limitations on lipid production by cryptococcus curvatus grown in Batch and fed Batch Culture
Process Biochemistry, 1996Co-Authors: Mainul Hassan, P J Blanc, Louismarie Granger, Alain Pareilleux, Gérard GomaAbstract:Abstract Cryptococcus curvatus , an oleaginous yeast, was grown under iron (Fe) and nitrogen (N)-limited conditions to produce lipid with a high stearic acid (C18:0) content in Batch and fed-Batch Culture. In Batch Culture, lack of ferrous ions had no evident effect on growth, lipid production or lipid composition. The highest stearic acid content in the total lipid was 14% in N-limited medium in Batch Culture. The combined effect of Fe and N-limitation in fed-Batch Culture was to increase the stearic acid content to 19% of the total lipids and the consumed carbon to nitrogen (C:N) ratio to 20 g/g. The highest biomass concentration achieved was 70 g/litre and 53% (w/w) lipid accumulated when grown for about 172 h in fed-Batch Culture. A C:N ratio between 20 and 50 was optimal for intracellular lipid accumulation and a ratio > 50 g/g became crucial for both growth and lipid production in fed-Batch Culture. The maximal C:N ratio achieved at the end of the Culture was 75 g/g. Lipid yield from glucose (g lipid/g glucose) was 0·14 and the fatty acids of lipids obtained were mainly oleic (C18:1), palmitic (C16:0) and stearic (C18:0).
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production of cocoa butter equivalents from prickly pear juice fermentation by an unsaturated fatty acid auxotroph of cryptococcus curvatus grown in Batch Culture
Process Biochemistry, 1995Co-Authors: Mainul Hassan, P J Blanc, Alain Pareilleux, Gérard GomaAbstract:An unsaturated fatty acid auxotroph derived from the oleaginous yeast Cryptococcus curvatus and named UfaM3 was defective in the conversion of stearic to oleic acid. It was cultivated on diluted (25%) prickly-pear juice in Batch Culture. The carbon to nitrogen ratio (C:N ratio) of the juice (44% glucose and 56% fructose content) was about 50 g/g. Differential utilization of glucose and fructose was observed. The efficiency of substrate conversion was 0·50 g/g for biomass and 0·21 g/g for lipids. The quality of lipids produced by UfaM3 approached cocoa butter.
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production of single cell oil from prickly pear juice fermentation by cryptococcus curvatus grown in Batch Culture
World Journal of Microbiology & Biotechnology, 1994Co-Authors: Mainul Hassan, P J Blanc, Alain Pareilleux, Gérard GomaAbstract:The biomass of Cryptococcus curvatus, an oleaginous yeast, reached 11 g/l and accumulated 46% (w/w) lipid when grown for 35 h in Batch Culture on diluted (25%) prickly-pear juice. The C:N ratio of the juice was about 50 g/g. The efficiency of substrate conversion was 0.48 g/g for biomass and 0.22 g/g for lipids. The extracted lipids were mainly oleic (18:1) and palmitic (16:0) acids and the quality of pipid approached that of palm oil.
Rosa Olivia Canizaresvillanueva - One of the best experts on this subject based on the ideXlab platform.
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Batch and fed Batch Culture of scenedesmus incrassatulus effect over biomass carotenoid profile and concentration photosynthetic efficiency and non photochemical quenching
Algal Research-Biomass Biofuels and Bioproducts, 2016Co-Authors: Juan Cristobal Garciacanedo, Eliseo Cristianiurbina, Cesar M Floresortiz, Teresa Poncenoyola, Fernando Esparzagarcia, Rosa Olivia CanizaresvillanuevaAbstract:Abstract The microalga Scenedesmus incrassatulus was cultivated in Batch and fed-Batch Culture modes under three different nitrogen concentrations (N). Considering that nitrogen limitation results in carotenoid accumulation, main objectives of this work were to assess carotenoid concentration and the following fluorescence parameters: maximum photosynthetic efficiency (Fv/Fm), operational photosynthetic efficiency (Fq′/Fm′) and the non-photochemical quenching (NPQ) at different N concentrations in the Culture media, using Batch and fed-Batch Culture modes. In all treatments, carotenoid concentration reached maximal level when N concentration in the medium was almost completely depleted. Carotenoid concentrations in fed-Batch treatments were up to 3 times higher than Batch Culture treatments. Maximum dry weight of 4.05 ± 0.04 g L − 1 and cell concentration of 8.24 × 10 7 cell mL − 1 was obtained using the higher N concentration in fed-Batch, these values were approximately 3 times higher than the obtained in Batch Culture. Fv/Fm showed the highest magnitude when the initial N concentration in the Culture medium was higher, for both Culture modes. Results showed that the fed-Batch Culture of S. incrassatulus promotes a higher Fv/Fm than Batch Culture (up to 0.78). The application of fed-Batch Culture had the effect of stabilizing the values of Fv/Fm during feeding period. In all fed-Batch treatments the maximum Fq′/Fm′ was detected during the feeding period, which had maximum values ranging from 0.47–0.58. In fed-Batch Culture mode NPQ showed no direct relationship with total carotenoid concentration. ETR was higher in fed Batch than in Batch cultivation. In Batch cultivation mode ETR had values ranging from 2 to 56 μmol electrons m − 2 s − 1 . ETR increased 6 fold in fed-Batch cultivation when irradiance was increased, having values up to 610 μmol electrons m − 2 s − 1 . A good cultivation strategy for biocompound production could be the use of fed Batch cultivation aimed to return nutrients like nitrogen to its initial condition.
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Batch and fed Batch Culture of scenedesmus incrassatulus effect over biomass carotenoid profile and concentration photosynthetic efficiency and non photochemical quenching
Algal Research-Biomass Biofuels and Bioproducts, 2016Co-Authors: Juan Cristobal Garciacanedo, Eliseo Cristianiurbina, Cesar M Floresortiz, Teresa Poncenoyola, Fernando Esparzagarcia, Rosa Olivia CanizaresvillanuevaAbstract:Abstract The microalga Scenedesmus incrassatulus was cultivated in Batch and fed-Batch Culture modes under three different nitrogen concentrations (N). Considering that nitrogen limitation results in carotenoid accumulation, main objectives of this work were to assess carotenoid concentration and the following fluorescence parameters: maximum photosynthetic efficiency (Fv/Fm), operational photosynthetic efficiency (Fq′/Fm′) and the non-photochemical quenching (NPQ) at different N concentrations in the Culture media, using Batch and fed-Batch Culture modes. In all treatments, carotenoid concentration reached maximal level when N concentration in the medium was almost completely depleted. Carotenoid concentrations in fed-Batch treatments were up to 3 times higher than Batch Culture treatments. Maximum dry weight of 4.05 ± 0.04 g L − 1 and cell concentration of 8.24 × 10 7 cell mL − 1 was obtained using the higher N concentration in fed-Batch, these values were approximately 3 times higher than the obtained in Batch Culture. Fv/Fm showed the highest magnitude when the initial N concentration in the Culture medium was higher, for both Culture modes. Results showed that the fed-Batch Culture of S. incrassatulus promotes a higher Fv/Fm than Batch Culture (up to 0.78). The application of fed-Batch Culture had the effect of stabilizing the values of Fv/Fm during feeding period. In all fed-Batch treatments the maximum Fq′/Fm′ was detected during the feeding period, which had maximum values ranging from 0.47–0.58. In fed-Batch Culture mode NPQ showed no direct relationship with total carotenoid concentration. ETR was higher in fed Batch than in Batch cultivation. In Batch cultivation mode ETR had values ranging from 2 to 56 μmol electrons m − 2 s − 1 . ETR increased 6 fold in fed-Batch cultivation when irradiance was increased, having values up to 610 μmol electrons m − 2 s − 1 . A good cultivation strategy for biocompound production could be the use of fed Batch cultivation aimed to return nutrients like nitrogen to its initial condition.
Sang Yup Lee - One of the best experts on this subject based on the ideXlab platform.
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constitutive production of human leptin by fed Batch Culture of recombinant rpos escherichia coli
Protein Expression and Purification, 2004Co-Authors: Ki Jun Jeong, Sang Yup Lee, Jong Hyun Choi, Won Min Yoo, Ki Chang Keum, Nae Choon Yoo, Moonhee SungAbstract:Abstract High-level production of human leptin by fed-Batch Culture of recombinant Escherichia coli using constitutive promoter system was investigated. For the constitutive expression of the obese gene encoding human leptin, the strong constitutive HCE promoter cloned from the d -amino acid aminotransferase gene of Geobacillus toebii was used. To develop an optimal host–vector system, several different recombinant E. coli strains were compared for leptin production. In flask Cultures, E. coli FMJ123, which is a rpoS mutant strain, showed the highest level of leptin production (41% of total proteins). By comparing the expression levels of leptin in several different rpoS − and rpoS + strains, it could be concluded that rpoS mutation positively affected constitutive production of leptin. For the large-scale production of human leptin, fed-Batch Cultures of recombinant E. coli FMJ123 were carried out using three different feeding solutions—chemically defined, yeast extract-containing, and casamino acid-containing feeding solutions. Among these, the use of casamino acid-containing feeding solution allowed production of leptin up to 2.1 g/L, which was 2.1- and 1.8-fold higher than that obtained with chemically defined and yeast extract-contained feeding solutions, respectively. These results suggest that the HCE promoter can be used for the efficient production of leptin, and most likely other recombinant proteins, in a constitutive manner.
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Production of poly(3-hydroxybutyrate) from whey by cell recycle fed-Batch Culture of recombinant Escherichia coli
Biotechnology Letters, 2001Co-Authors: Woo Suk Ahn, Si Jae Park, Sang Yup LeeAbstract:A new fermentation strategy using cell recycle membrane system was developed for the efficient production of poly(3-hydroxybutyrate) (PHB) from whey by recombinant Escherichia coli strain CGSC 4401 harboring the Alcaligenes latus polyhydroxyalkanoate (PHA) biosynthesis genes. By cell recycle, fed-Batch cultivation employing an external membrane module, the working volume of fermentation could be constantly maintained at 2.3 l. The final cell concentration, PHB concentration and PHB content of 194 g l−1, 168 g l−1 and 87%, respectively, were obtained in 36.5 h by the pH-stat cell recycle fed-Batch Culture using whey solution concentrated to contain 280 g lactose l−1 as a feeding solution, resulting in a high productivity of 4.6 g PHB l−1 h−1.
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production of poly 3 hydroxybutyrate by fed Batch Culture of filamentation suppressed recombinant escherichia coli
Applied and Environmental Microbiology, 1997Co-Authors: Fulai Wang, Sang Yup LeeAbstract:Recombinant Escherichia coli XL1-Blue harboring a high-copy-number plasmid containing the Alcaligenes eutrophus polyhydroxyalkanoate synthesis genes could efficiently synthesize poly(3-hydroxybutyrate) (PHB) in a complex medium containing yeast extract and tryptone but not in a defined medium. One of the reasons for the reduced PHB production in a defined medium was thought to be severe filamentation of cells in this medium. By overexpressing an essential cell division protein, FtsZ, in recombinant E. coli producing PHB, filamentation could be suppressed and PHB could be efficiently produced in a defined medium. A high PHB concentration of 149 g/liter, with high productivity of 3.4 g of PHB/liter/h, could be obtained by the pH-stat fed-Batch Culture of the filamentation-suppressed recombinant E. coli in a defined medium. It was also found that insufficient oxygen supply at a dissolved oxygen concentration (DOC) of 1 to 3% of air saturation during active PHB synthesis phase did not negatively affect PHB production. By growing cells to the concentration of 110 g/liter and then controlling the DOC in the range of 1 to 3% of air saturation, a PHB concentration of 157 g/liter and PHB productivity of 3.2 g of PHB/liter/h were obtained. For the scale-up studies, fed-Batch Culture was carried out in a 50-liter stirred tank fermentor, in which the DOC decreased to zero when cell concentration reached 50 g/liter. However, a relatively high PHB concentration of 101 g/liter and PHB productivity of 2.8 g of PHB/liter/h could still be obtained, which demonstrated the possibility of industrial production of PHB in a defined medium by employing the filamentation-suppressed recombinant E. coli.
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production of poly 3 hydroxybutyric acid by fed Batch Culture of alcaligenes eutrophus with glucose concentration control
Biotechnology and Bioengineering, 1994Co-Authors: Beom Soo Kim, Ho Nam Chang, Sang Yup Lee, Yong Keun Chang, Seungchul Lee, Seong Ihl WooAbstract:Alcaligenes eutrophus NCIMB 11599 was cultivated to produce poly(3-hydroxybutyric acid) (PHB) from glucose by the automatic fed-Batch Culture technique. The glucose concentration of the Culture broth was controlled at 10 to 20 g/L by two methods: using exit gas data obtained from a mass spectrometer and using an on-line glucose analyzer. The effect of ammonium limitation on PHB synthesis at different Culture phases was studied. The final cell concentration, PHB concentration, and PHB productivity increased as ammonia feeding was stopped at a higher cell concentration. High concentrations of PHB (121 g/L) and total cells (164 g/L) were obtained in 50 h when ammonia feeding was stopped at the cell concentration of 70 g/L. The maximum PHB content reached 76% of dry cell weight and the productivity was 2.42 g/L h with the yield of 0.3 g PHB/g glucose.
Juan Cristobal Garciacanedo - One of the best experts on this subject based on the ideXlab platform.
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Batch and fed Batch Culture of scenedesmus incrassatulus effect over biomass carotenoid profile and concentration photosynthetic efficiency and non photochemical quenching
Algal Research-Biomass Biofuels and Bioproducts, 2016Co-Authors: Juan Cristobal Garciacanedo, Eliseo Cristianiurbina, Cesar M Floresortiz, Teresa Poncenoyola, Fernando Esparzagarcia, Rosa Olivia CanizaresvillanuevaAbstract:Abstract The microalga Scenedesmus incrassatulus was cultivated in Batch and fed-Batch Culture modes under three different nitrogen concentrations (N). Considering that nitrogen limitation results in carotenoid accumulation, main objectives of this work were to assess carotenoid concentration and the following fluorescence parameters: maximum photosynthetic efficiency (Fv/Fm), operational photosynthetic efficiency (Fq′/Fm′) and the non-photochemical quenching (NPQ) at different N concentrations in the Culture media, using Batch and fed-Batch Culture modes. In all treatments, carotenoid concentration reached maximal level when N concentration in the medium was almost completely depleted. Carotenoid concentrations in fed-Batch treatments were up to 3 times higher than Batch Culture treatments. Maximum dry weight of 4.05 ± 0.04 g L − 1 and cell concentration of 8.24 × 10 7 cell mL − 1 was obtained using the higher N concentration in fed-Batch, these values were approximately 3 times higher than the obtained in Batch Culture. Fv/Fm showed the highest magnitude when the initial N concentration in the Culture medium was higher, for both Culture modes. Results showed that the fed-Batch Culture of S. incrassatulus promotes a higher Fv/Fm than Batch Culture (up to 0.78). The application of fed-Batch Culture had the effect of stabilizing the values of Fv/Fm during feeding period. In all fed-Batch treatments the maximum Fq′/Fm′ was detected during the feeding period, which had maximum values ranging from 0.47–0.58. In fed-Batch Culture mode NPQ showed no direct relationship with total carotenoid concentration. ETR was higher in fed Batch than in Batch cultivation. In Batch cultivation mode ETR had values ranging from 2 to 56 μmol electrons m − 2 s − 1 . ETR increased 6 fold in fed-Batch cultivation when irradiance was increased, having values up to 610 μmol electrons m − 2 s − 1 . A good cultivation strategy for biocompound production could be the use of fed Batch cultivation aimed to return nutrients like nitrogen to its initial condition.
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Batch and fed Batch Culture of scenedesmus incrassatulus effect over biomass carotenoid profile and concentration photosynthetic efficiency and non photochemical quenching
Algal Research-Biomass Biofuels and Bioproducts, 2016Co-Authors: Juan Cristobal Garciacanedo, Eliseo Cristianiurbina, Cesar M Floresortiz, Teresa Poncenoyola, Fernando Esparzagarcia, Rosa Olivia CanizaresvillanuevaAbstract:Abstract The microalga Scenedesmus incrassatulus was cultivated in Batch and fed-Batch Culture modes under three different nitrogen concentrations (N). Considering that nitrogen limitation results in carotenoid accumulation, main objectives of this work were to assess carotenoid concentration and the following fluorescence parameters: maximum photosynthetic efficiency (Fv/Fm), operational photosynthetic efficiency (Fq′/Fm′) and the non-photochemical quenching (NPQ) at different N concentrations in the Culture media, using Batch and fed-Batch Culture modes. In all treatments, carotenoid concentration reached maximal level when N concentration in the medium was almost completely depleted. Carotenoid concentrations in fed-Batch treatments were up to 3 times higher than Batch Culture treatments. Maximum dry weight of 4.05 ± 0.04 g L − 1 and cell concentration of 8.24 × 10 7 cell mL − 1 was obtained using the higher N concentration in fed-Batch, these values were approximately 3 times higher than the obtained in Batch Culture. Fv/Fm showed the highest magnitude when the initial N concentration in the Culture medium was higher, for both Culture modes. Results showed that the fed-Batch Culture of S. incrassatulus promotes a higher Fv/Fm than Batch Culture (up to 0.78). The application of fed-Batch Culture had the effect of stabilizing the values of Fv/Fm during feeding period. In all fed-Batch treatments the maximum Fq′/Fm′ was detected during the feeding period, which had maximum values ranging from 0.47–0.58. In fed-Batch Culture mode NPQ showed no direct relationship with total carotenoid concentration. ETR was higher in fed Batch than in Batch cultivation. In Batch cultivation mode ETR had values ranging from 2 to 56 μmol electrons m − 2 s − 1 . ETR increased 6 fold in fed-Batch cultivation when irradiance was increased, having values up to 610 μmol electrons m − 2 s − 1 . A good cultivation strategy for biocompound production could be the use of fed Batch cultivation aimed to return nutrients like nitrogen to its initial condition.