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Eric Samain - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of 6 sialyllactose 6 6 disialyllactose and 6 kdo lactose by metabolically engineered e coli expressing a multifunctional sialyltransferase from the photobacterium sp jt ish 224
Carbohydrate Research, 2010Co-Authors: Sophie Drouillard, Hitomi Kajiwara, Toshiki Mine, Takeshi Yamamoto, Eric SamainAbstract:We have previously reported the efficient conversion of lactose into 3'-sialyllactose by high cell density cultures of a genetically engineered Escherichia coli strain expressing the Neisseria meningitidis gene for alpha-(2-->3)-sialyltransferase [Fierfort, N.; Samain, E. J. Biotechnol. 2008, 134, 261-265.]. First attempts to use a similar strategy to produce 6'-sialyllactose with a strain expressing alpha-(2-->6)-sialyltransferase from the Photobacterium sp. JT-ISH-224 led to the production of a trisaccharide that was identified as KDO-lactose (2-keto-3-deoxy-manno-octonyllactose). This result showed that alpha-(2-->6)-sialyltransferase was able to use CMP-KDO as sugar donor and preferentially used CMP-KDO over CMP-Neu5Ac. By reducing the expression level of the sialyltransferase gene and increasing that of the neuABC genes, we have been able to favour the formation of 6'-sialyllactose and to prevent the formation of KDO-lactose. However, in this case, a third lactose derivative, which was identified as 6,6'-disialyllactose, was also produced. Formation of 6,6'-disialyllactose was mainly observed under conditions of lactose shortage. On the other hand, when the culture was continuously fed with an excess of lactose, 6'-sialyllactose was almost the only product detected and its final concentration was higher than 30g/L of culture medium.
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a new fermentation process allows large scale production of human milk oligosaccharides by metabolically engineered bacteria
Glycobiology, 2002Co-Authors: Bernard Priem, Michel Gilbert, Warren W Wakarchuk, Alain Heyraud, Eric SamainAbstract:When fed to a beta-galactosidase-negative (lacZ(-)) Escherichia coli strain that was grown on an alternative carbon source (such as glycerol), lactose accumulated intracellularly on induction of the lactose permease. We showed that intracellular lactose was efficiently glycosylated when genes of glycosyltransferase that use lactose as acceptor were expressed. High-cell-density cultivation of lacZ(-) strains that overexpressed the beta 1,3 N acetyl glucosaminyltransferase lgtA gene of Neisseria meningitidis resulted in the synthesis of 6 g x L(-1) of the expected trisaccharide (GlcNAc beta 1-3Gal beta 1-4Glc). When the beta 1,4 galactosyltransferase lgtB gene of N. meningitidis was coexpressed with lgtA, the trisaccharide was further converted to lacto-N-neotetraose (Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc) and lacto-N-neoheaxose with a yield higher than 5 g x L(-1). In a similar way, the nanA(-) E. coli strain that was devoid of NeuAc aldolase activity accumulated NeuAc on induction of the NanT permease and the lacZ(-) nanA(-) strain that overexpressed the N. meningitidis genes of the alpha2,3 sialyltransferase and of the CMP-NeuAc synthase efficiently produced sialyllactose (NeuAc alpha 2-3Gal beta 1-4Glc) from exogenous NeuAc and lactose.
Takeshi Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of 6 sialyllactose 6 6 disialyllactose and 6 kdo lactose by metabolically engineered e coli expressing a multifunctional sialyltransferase from the photobacterium sp jt ish 224
Carbohydrate Research, 2010Co-Authors: Sophie Drouillard, Hitomi Kajiwara, Toshiki Mine, Takeshi Yamamoto, Eric SamainAbstract:We have previously reported the efficient conversion of lactose into 3'-sialyllactose by high cell density cultures of a genetically engineered Escherichia coli strain expressing the Neisseria meningitidis gene for alpha-(2-->3)-sialyltransferase [Fierfort, N.; Samain, E. J. Biotechnol. 2008, 134, 261-265.]. First attempts to use a similar strategy to produce 6'-sialyllactose with a strain expressing alpha-(2-->6)-sialyltransferase from the Photobacterium sp. JT-ISH-224 led to the production of a trisaccharide that was identified as KDO-lactose (2-keto-3-deoxy-manno-octonyllactose). This result showed that alpha-(2-->6)-sialyltransferase was able to use CMP-KDO as sugar donor and preferentially used CMP-KDO over CMP-Neu5Ac. By reducing the expression level of the sialyltransferase gene and increasing that of the neuABC genes, we have been able to favour the formation of 6'-sialyllactose and to prevent the formation of KDO-lactose. However, in this case, a third lactose derivative, which was identified as 6,6'-disialyllactose, was also produced. Formation of 6,6'-disialyllactose was mainly observed under conditions of lactose shortage. On the other hand, when the culture was continuously fed with an excess of lactose, 6'-sialyllactose was almost the only product detected and its final concentration was higher than 30g/L of culture medium.
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Photobacterium sp. JT-ISH-224 Produces Two Sialyltransferases, α-/β-Galactoside α2,3-Sialyltransferase and β-Galactoside α2,6-Sialyltransferase
Journal of biochemistry, 2007Co-Authors: Hiroshi Tsukamoto, Toshiki Mine, Yoshimitsu Takakura, Takeshi YamamotoAbstract:A novel bacterium, Photobacterium sp. JT-ISH-224, that produces alpha-/beta-galactoside alpha2,3-sialyltransferase and beta-galactoside alpha2,6-sialyltransferase, was isolated from the gut of a Japanese barracuda. The genes that encode the enzymes were cloned from the genomic library of the bacterium using the genes encoding alpha-/beta-galactoside alpha2,3-sialyltransferase from P. phosphoreum and beta-galactoside alpha2,6-sialyltransferase from P. damselae as probes. The nucleotide sequences were determined, and open reading frames of 1,230 and 1,545 bp for encoding an alpha2,3-sialyltransferase and an alpha2,6-sialyltransferase of 409- and 514-amino acid residues, respectively, were identified. The alpha2,3-sialyltransferase had 92% amino acid sequence identity with the P. phosphoreum alpha2,3-sialyltransferase, whereas the alpha2,6-sialyltransferase had 54% amino acid sequence identity with the P. damselae alpha2,6-sialyltransferase. For both enzymes, the DNA fragments that encoded the full-length protein and its truncated form lacking the putative signal peptide sequence were amplified by a polymerase chain reaction and cloned into an expression vector. Each gene was expressed in Escherichia coli, and the lysate from each strain had enzymatic activity. The alpha2,3-sialyltransferase catalysed the transfer of N-acetylneuraminic acid (NeuAc) from CMP-NeuAc to lactose, alpha-methyl-galactopyranoside and beta-methyl-galactopyranoside with low apparent K(m) and the alpha2,6-sialyltransferase catalysed the transfer of NeuAc from CMP-NeuAc to lactose with low apparent K(m).
Adelson Joel Da ,silva - One of the best experts on this subject based on the ideXlab platform.
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Detecção e caracterização de complexos multi-enzimáticos em secretoma de fungos filamentosos
2013Co-Authors: Adelson Joel Da ,silvaAbstract:As enzimas que degradam parede celular vegetal produzidas por micro-organismos possuem aplicações biotecnológicas importantes, incluindo a produção de bioetanol. Algumas batérias anaeróbicas são capazes de produzir complexos multi-enzimáticos chamados de celulosomos, enquanto os fungos filamentosos normalmente secretam enzimas hidrolíticas individuais que atuam sinergisticamente no processo de degradação de polissacarídeo. Neste trabalho, nós mostramos que os fungos filamentosos Trichoderma harzianum e Trichoderma reesei, secretam complexos multi-enzimáticos ativos quando cultivados em meio contendo o resíduo agrícula bagaço de cana-de-açucar e lactose (ou galactose), respectivamente. O secretoma de ambos os fungos foram analisadas primeiramente por 1D-BN (blue native)-PAGE. Bandas eletroforéticas correspondendo a possíveis complexos foram submetidas à separação eletroforética usando sistema Tricina-SDS-PAGE para demonstrar que são constituídas de componentes menores. Ensaios zimográficos foram realizados usando 1D-BN-PAGE e 2D-BN/BN-PAGE para verificar atividades celulolítica e xilanolítica em um mesmo complexo. Finalmente, os complexos foram digeridas por tripsina e analisadas separadamente por LC-MS/MS e os programas MASCOT e MS-BLAST para identificação das proteínas constituintes. Os resultados mostraram que ambos os fungos produzem complexos constituídos por enzimas celulolítica e xilanolítica e outras proteínas, as quais apresentam uma complementariedade funcional no processo de degração de substratos polissacaridícos. Em T. harzianum foram analisados três complexos, os quais apresentaram os seguintes componentes: celobiohidrolase I, celobiohidrolase I-II, alfa-L-arabinofuranosidase, xilana 1,4- -xilosidase (complexo I); acetilxilan esterase, ndoquitinase, arabinogalactana, endo-1,4- -galactosidase, celobiohidrolase I, cutinase, ?-N-arabinofuranosidase e endo- -1,4-xilanase (complexo II); glucoamilase, endo-beta-1,4- glucanase, swollenina, beta-endoglucanase ancorado a GPI, alfa-L-arabinofuranosidase, ?-1,3-glucanase (complexo III). T. reesei produziu mais complexos multi-enzimáticos quando cultivado em meio contendo lactose que galactose. A composição dos complexos I e II em lactose parece torná-los melhores equipados para biodegradação. Os componentes dos complexos do meio com lactose são: glicosil hidrolases 20, 36, beta-1,3-endoglucanase, alfa-alactosidase, exo-beta-1,4-glucanase, aril-alcool oxidase, "predicted protein" 43, "predicted protein" 20 (complexo I); beta-1,3-endoglucanase, "predicted protein" 20, 48, 44, 61, 52, 42, glicosil hidrolase 37, quitinase (complexo II). Os complexos do meio com galactose são: glicosil hidrolases 16, 36, 54, 55, beta-1,3-endoglucanase, catalase/peroxidase bifuncional, "predicted protein" 20 (complexo I); "predicted protein" 20, 44, 61, 52, beta-1,3-endoglucanase, glicosil hidrolase 3, 37, quitinase, amidase (complexo II). Além disso, o complexo I é mais expresso em meio contendo lactose que galactose, ocorrendo inversamente com o complexo II. Juntos, esses dados mostram que a fonte de carbono influi na composição dos complexos multi-enzimáticos em T. reesei. A cooperatividade funcional entre os elementos dos complexos dos fungos são discutidos. ______________________________________________________________________________ ABSTRACTPlant cell degrading enzymes produced by microorganisms possess important biotechnological applications; including the production of bioethanol . Some anaerobic bacteria are abl e to produce multienzymatic complexes called cellulosomes whilst filamentous fungi normally secrete individual hydrolytic enzymes that act synergically in the process of polysaccharide degradation. I n the present work we demonstrated that the filamentous fungi Trichoderma harzianum and Trichoderma reesei secrete active multienzymatic complexes when culti vated i n culture media suppl emented with the agricultural residue sugarcane bagasse and lactose (gal actose), respecti vely. The secret ome of bot h f ungi were analysed by 1D-BN (blue native) PAGE. Protein bands corresponding to possible complexes were submitted to electrophoretic separation using a Tricine-SDS system in order to demonstrate that they were constituted by smaller components. Zymogr aphic assays were performed using 1D-BN-PAGE and 2D-BN/BN-PAGE o verify cellulolytic and cellulolytic activities in the complexes. Finally, the complexes were trypsin di gested, subjected to LC-MS/MS and the results analyzed using the soft ware MASCOT and MS-BLAST to identify t hei r component s. The results demonstrated t hat both organisms produced complexes constituted by cellulolytic and xylanolytic enzymes as well as other protei ns relat ed to polysacchari de degradation. Three T. harzianum complexes that were analyzed presented the following components: cellobiohydrolase I, cellobiohydrolase I-II, al pha-L-arabinofuranosidase, xylan 1,4- - xylosidase (compl ex I); acetilxylan esterase, endochitinase, arabinogalactan, endo-1, 4- -galactosidase, cellobiohydrolase I, cutinase, -N-arabi nofuranosidase e endo- -1,4-xylanase (complex II); glucoamilase, endo-beta-1,4-glucanase, swollenin, GPI-anchored beta-endoglucanase, alpha-L-arabinofuranosi dase and -1,3-glucanase (compl exo III). T. reesei produced more multienzymatic compl exes when grown in lactose than in galactose containi ng medium. The composition of compl exes I and II in lactose possibly make them more suitable for biodegradation. The component s of t he compl exes produced i n t he l act ose medium are: glycosyl hydrolases 20, 36, beta-1,3-endogl ucanase, alpha-gal actosidase, exo-bet a-1, 4-glucanase, aryl - 1, 3- ex II). The compl exes produced in the gal actose medi um are glycosil hydrolases 16, 36, 54, 55, bet a-1, 3- 20, 44, 61, 52, bet a-1, 3-endoglucanase, glycosyl hydrolase 3, 37, chitinase and ami dase (complex II). In addition, compl ex I is more expressed in l actose than in gal actose medium whil e compl ex II is more expressed in galactose. Overall, the dat a show that the carbon source infl uence the composition of T. reesei multienzimatic complexes. The functional cooperativity between the elements of the complexes are discussed
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Detecção e caracterização de complexos multi-enzimáticos em secretoma de fungos filamentosos
2012Co-Authors: Adelson Joel Da ,silvaAbstract:Tese (doutorado)— Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Biologia Celular, 2012.As enzimas que degradam parede celular vegetal produzidas por micro-organismos possuem aplicações biotecnológicas importantes, incluindo a produção de bioetanol. Algumas batérias anaeróbicas são capazes de produzir complexos multi-enzimáticos chamados de celulosomos, enquanto os fungos filamentosos normalmente secretam enzimas hidrolíticas individuais que atuam sinergisticamente no processo de degradação de polissacarídeo. Neste trabalho, nós mostramos que os fungos filamentosos Trichoderma harzianum e Trichoderma reesei, secretam complexos multi-enzimáticos ativos quando cultivados em meio contendo o resíduo agrícula bagaço de cana-de-açucar e lactose (ou galactose), respectivamente. O secretoma de ambos os fungos foram analisadas primeiramente por 1D-BN (blue native)-PAGE. Bandas eletroforéticas correspondendo a possíveis complexos foram submetidas à separação eletroforética usando sistema Tricina-SDS-PAGE para demonstrar que são constituídas de componentes menores. Ensaios zimográficos foram realizados usando 1D-BN-PAGE e 2D-BN/BN-PAGE para verificar atividades celulolítica e xilanolítica em um mesmo complexo. Finalmente, os complexos foram digeridas por tripsina e analisadas separadamente por LC-MS/MS e os programas MASCOT e MS-BLAST para identificação das proteínas constituintes. Os resultados mostraram que ambos os fungos produzem complexos constituídos por enzimas celulolítica e xilanolítica e outras proteínas, as quais apresentam uma complementariedade funcional no processo de degração de substratos polissacaridícos. Em T. harzianum foram analisados três complexos, os quais apresentaram os seguintes componentes: celobiohidrolase I, celobiohidrolase I-II, alfa-L-arabinofuranosidase, xilana 1,4- -xilosidase (complexo I); acetilxilan esterase, ndoquitinase, arabinogalactana, endo-1,4- -galactosidase, celobiohidrolase I, cutinase, ?-N-arabinofuranosidase e endo- -1,4-xilanase (complexo II); glucoamilase, endo-beta-1,4- glucanase, swollenina, beta-endoglucanase ancorado a GPI, alfa-L-arabinofuranosidase, ?-1,3-glucanase (complexo III). T. reesei produziu mais complexos multi-enzimáticos quando cultivado em meio contendo lactose que galactose. A composição dos complexos I e II em lactose parece torná-los melhores equipados para biodegradação. Os componentes dos complexos do meio com lactose são: glicosil hidrolases 20, 36, beta-1,3-endoglucanase, alfa-alactosidase, exo-beta-1,4-glucanase, aril-alcool oxidase, "predicted protein" 43, "predicted protein" 20 (complexo I); beta-1,3-endoglucanase, "predicted protein" 20, 48, 44, 61, 52, 42, glicosil hidrolase 37, quitinase (complexo II). Os complexos do meio com galactose são: glicosil hidrolases 16, 36, 54, 55, beta-1,3-endoglucanase, catalase/peroxidase bifuncional, "predicted protein" 20 (complexo I); "predicted protein" 20, 44, 61, 52, beta-1,3-endoglucanase, glicosil hidrolase 3, 37, quitinase, amidase (complexo II). Além disso, o complexo I é mais expresso em meio contendo lactose que galactose, ocorrendo inversamente com o complexo II. Juntos, esses dados mostram que a fonte de carbono influi na composição dos complexos multi-enzimáticos em T. reesei. A cooperatividade funcional entre os elementos dos complexos dos fungos são discutidos. ______________________________________________________________________________ ABSTRACTPlant cell degrading enzymes produced by microorganisms possess important biotechnological applications; including the production of bioethanol . Some anaerobic bacteria are abl e to produce multienzymatic complexes called cellulosomes whilst filamentous fungi normally secrete individual hydrolytic enzymes that act synergically in the process of polysaccharide degradation. I n the present work we demonstrated that the filamentous fungi Trichoderma harzianum and Trichoderma reesei secrete active multienzymatic complexes when culti vated i n culture media suppl emented with the agricultural residue sugarcane bagasse and lactose (gal actose), respecti vely. The secret ome of bot h f ungi were analysed by 1D-BN (blue native) PAGE. Protein bands corresponding to possible complexes were submitted to electrophoretic separation using a Tricine-SDS system in order to demonstrate that they were constituted by smaller components. Zymogr aphic assays were performed using 1D-BN-PAGE and 2D-BN/BN-PAGE o verify cellulolytic and cellulolytic activities in the complexes. Finally, the complexes were trypsin di gested, subjected to LC-MS/MS and the results analyzed using the soft ware MASCOT and MS-BLAST to identify t hei r component s. The results demonstrated t hat both organisms produced complexes constituted by cellulolytic and xylanolytic enzymes as well as other protei ns relat ed to polysacchari de degradation. Three T. harzianum complexes that were analyzed presented the following components: cellobiohydrolase I, cellobiohydrolase I-II, al pha-L-arabinofuranosidase, xylan 1,4- - xylosidase (compl ex I); acetilxylan esterase, endochitinase, arabinogalactan, endo-1, 4- -galactosidase, cellobiohydrolase I, cutinase, -N-arabi nofuranosidase e endo- -1,4-xylanase (complex II); glucoamilase, endo-beta-1,4-glucanase, swollenin, GPI-anchored beta-endoglucanase, alpha-L-arabinofuranosi dase and -1,3-glucanase (compl exo III). T. reesei produced more multienzymatic compl exes when grown in lactose than in galactose containi ng medium. The composition of compl exes I and II in lactose possibly make them more suitable for biodegradation. The component s of t he compl exes produced i n t he l act ose medium are: glycosyl hydrolases 20, 36, beta-1,3-endogl ucanase, alpha-gal actosidase, exo-bet a-1, 4-glucanase, aryl - 1, 3- ex II). The compl exes produced in the gal actose medi um are glycosil hydrolases 16, 36, 54, 55, bet a-1, 3- 20, 44, 61, 52, bet a-1, 3-endoglucanase, glycosyl hydrolase 3, 37, chitinase and ami dase (complex II). In addition, compl ex I is more expressed in l actose than in gal actose medium whil e compl ex II is more expressed in galactose. Overall, the dat a show that the carbon source infl uence the composition of T. reesei multienzimatic complexes. The functional cooperativity between the elements of the complexes are discussed
Toshiki Mine - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of 6 sialyllactose 6 6 disialyllactose and 6 kdo lactose by metabolically engineered e coli expressing a multifunctional sialyltransferase from the photobacterium sp jt ish 224
Carbohydrate Research, 2010Co-Authors: Sophie Drouillard, Hitomi Kajiwara, Toshiki Mine, Takeshi Yamamoto, Eric SamainAbstract:We have previously reported the efficient conversion of lactose into 3'-sialyllactose by high cell density cultures of a genetically engineered Escherichia coli strain expressing the Neisseria meningitidis gene for alpha-(2-->3)-sialyltransferase [Fierfort, N.; Samain, E. J. Biotechnol. 2008, 134, 261-265.]. First attempts to use a similar strategy to produce 6'-sialyllactose with a strain expressing alpha-(2-->6)-sialyltransferase from the Photobacterium sp. JT-ISH-224 led to the production of a trisaccharide that was identified as KDO-lactose (2-keto-3-deoxy-manno-octonyllactose). This result showed that alpha-(2-->6)-sialyltransferase was able to use CMP-KDO as sugar donor and preferentially used CMP-KDO over CMP-Neu5Ac. By reducing the expression level of the sialyltransferase gene and increasing that of the neuABC genes, we have been able to favour the formation of 6'-sialyllactose and to prevent the formation of KDO-lactose. However, in this case, a third lactose derivative, which was identified as 6,6'-disialyllactose, was also produced. Formation of 6,6'-disialyllactose was mainly observed under conditions of lactose shortage. On the other hand, when the culture was continuously fed with an excess of lactose, 6'-sialyllactose was almost the only product detected and its final concentration was higher than 30g/L of culture medium.
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Photobacterium sp. JT-ISH-224 Produces Two Sialyltransferases, α-/β-Galactoside α2,3-Sialyltransferase and β-Galactoside α2,6-Sialyltransferase
Journal of biochemistry, 2007Co-Authors: Hiroshi Tsukamoto, Toshiki Mine, Yoshimitsu Takakura, Takeshi YamamotoAbstract:A novel bacterium, Photobacterium sp. JT-ISH-224, that produces alpha-/beta-galactoside alpha2,3-sialyltransferase and beta-galactoside alpha2,6-sialyltransferase, was isolated from the gut of a Japanese barracuda. The genes that encode the enzymes were cloned from the genomic library of the bacterium using the genes encoding alpha-/beta-galactoside alpha2,3-sialyltransferase from P. phosphoreum and beta-galactoside alpha2,6-sialyltransferase from P. damselae as probes. The nucleotide sequences were determined, and open reading frames of 1,230 and 1,545 bp for encoding an alpha2,3-sialyltransferase and an alpha2,6-sialyltransferase of 409- and 514-amino acid residues, respectively, were identified. The alpha2,3-sialyltransferase had 92% amino acid sequence identity with the P. phosphoreum alpha2,3-sialyltransferase, whereas the alpha2,6-sialyltransferase had 54% amino acid sequence identity with the P. damselae alpha2,6-sialyltransferase. For both enzymes, the DNA fragments that encoded the full-length protein and its truncated form lacking the putative signal peptide sequence were amplified by a polymerase chain reaction and cloned into an expression vector. Each gene was expressed in Escherichia coli, and the lysate from each strain had enzymatic activity. The alpha2,3-sialyltransferase catalysed the transfer of N-acetylneuraminic acid (NeuAc) from CMP-NeuAc to lactose, alpha-methyl-galactopyranoside and beta-methyl-galactopyranoside with low apparent K(m) and the alpha2,6-sialyltransferase catalysed the transfer of NeuAc from CMP-NeuAc to lactose with low apparent K(m).
Dominikus Noll - One of the best experts on this subject based on the ideXlab platform.
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optimal control of crystallization of alpha lactose monohydrate
Asian Control Conference, 2013Co-Authors: Amira Rachah, Dominikus NollAbstract:We present a mathematical model for solvated crystallization of a-lactose monohydrate in semi-batch mode. The process dynamics are governed by conservation laws including population, molar and energy balance equations. We present and discuss the model and then control the process with the goal to privilege the production of small particles in the range between 10-5 and 10-4μm. We compare several specific and unspecific cost functions leading to optimal strategies with significantly different effects on product quality. Control inputs are temperature, feed rate, and the choice of an appropriate crystal seed.
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controle de la cristallisation du alpha lactose monohydrate
CRISTAL 7 -7ème édition du colloque Cristallisation et précipitation industrielles, 2013Co-Authors: Amira Rachah, Fabienne Espitalier, Fabien Baillon, Dominikus NollAbstract:La cristallisation est une operation utilisee dans differents domaines industriels comme la pharmacie, l'agro-alimentaire ou la chimie fine. Ce processus consiste a isoler un produit en solution pour le recuperer sous forme solide dans l'objectif de conferer au solide synthetise des specifications voulues en vue de controler ses proprietes d'usage. Un grand interet est porte a l'etude du processus de cristallisation afin de le maitriser, et donc d'ameliorer les proprietes du produit final. Un modele dynamique fiable decrivant les phenomenes mis en jeu est necessaire pour l'etudier, et appliquer des strategies de controle afin de produire des solides conformes aux cahiers des charges et aux exigences industrielles. Dans ce travail, nous nous interessons a la cristallisation du α-lactose monohydrate en mode semi-continu avec ensemencement. Le lactose est un sucre reducteur present dans le lait, qui existe sous deux formes anomeriques α et β en solution (mutarotation). La modelisation mathematique de la cristallisation du α-lactose monohydrate comprend le bilan de population sur les cristaux de α-lactose monohydrate, les bilans de matieres sur le α-lactose, le β-lactose et l'eau, avec prise en compte de la mutarotation et le bilan d'energie. Cette etude presente le controle du processus de cristallisation selon deux objectifs d'optimisation : minimisation du taux de nucleation et minimisation du coefficient de variation de la distribution de taille en volume.