Biotechnological production of a new range of surfactants: Trehalose and fatty acid esters

Texte intégral accessible uniquement aux membres de l'Université de Lorraine The aim of this work was to study the enzymic synthesis of esters from trehalose and fatty acids by an immobilized lipase from Candida antarctica . The reaction was carried out in low water contend media. At first, the...

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Bibliographic Details
Main Author: Hugon, Delphine
Other Authors: Laboratoire des Sciences du Génie Chimique (LSGC), Institut National Polytechnique de Lorraine (INPL)-Centre National de la Recherche Scientifique (CNRS), Institut National Polytechnique de Lorraine, Mohamed Ghoul, J.M. Engasser
Format: Doctoral or Postdoctoral Thesis
Language:French
Published: HAL CCSD 2000
Subjects:
Online Access:https://hal.univ-lorraine.fr/tel-01750487
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Summary:Texte intégral accessible uniquement aux membres de l'Université de Lorraine The aim of this work was to study the enzymic synthesis of esters from trehalose and fatty acids by an immobilized lipase from Candida antarctica . The reaction was carried out in low water contend media. At first, the reactional system was selected: direct esterification was chosen ruther than transesterification on conversion yields and final product concentrations grounds. Second1y, the influence of the medium composition, and particularly of çe1argonic acid concentration, temperature, water con tend and substrate feed on the performances of the trehalose pelargonates synthesis was evaluated. Then, kinetic studies on the synthesis of other threalose esters have been performed. At last, the reaction equilibria were analyzed by simulating the effects of the following parameters: water con tend, fatty acids and trehalose concentrations.This work has allowed to show the huge influence of the water con tend parameter on both the conversion of substrates and the selectivity of reaction. This parameter is all the more important as the carbohydrate concentration is low. The fatty acid concentration plays too an role on the reaction equilibria, especially at the selectivity level. L'objectif général de ce travail est l'étude de la réaction de synthèse enzymatique d'esters de tréhalose et d'acides gras par la lipase immobilisée de Candida antarctica. Cette réaction est faite dans un milieu réactionnel à faible teneur en eau. Ce travail comporte plusieurs parties. Dans un premier temps, nous avons défini le système réactionnel avec lequel nous avons travaillé : l'estérification directe donne de meilleures performances en termes de rendements de conversion et de concentrations en esters produits que la transestérification. Dans un second temps, nous avons étudié l'influence de la composition du milieu (concentration en acide pélargonique, température, teneur en eau, ajout de substrat) sur les performances de la réaction de synthèse de ...