title: A novel reactive perstraction system based on liquid-core microcapsules applied to lipase-catalyzed biotransformations.
abstract: A novel reactive perstraction system has been developed based on liquid-core capsules, involving an enzyme-catalyzed reaction coupled with simultaneous in situ product recovery. Lipase-catalyzed reactions, hydrolysis of triprionin and nitrophenyl laurate, were selected to test the system and demonstrate the feasibility of immobilization of enzymes to the membranes of liquid-core capsules and the ability to extract hydrophobic products of the reaction within the capsule core. The lipase from Candida rugosa was immobilized to the microcapsules by adsorption and by covalent binding through activation with glutaraldehyde. In both cases improved temperature and operational stability were achieved. Both types of immobilization resulted in a basic shift of the pH optimum for activity, from 7.5 to 9.0. The presence of an organic phase within the capsule core allowed direct product separation and lead to a decrease in product inhibition of the lipase-catalyzed reaction.
authors.affiliation: Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology, EPFL, CH-1015 Lausanne, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Wyss
authors.forename: U
authors.initials: U
authors.lastname: von Stockar
authors.forename: I W
authors.initials: IW
authors.lastname: Marison
mesh_terms: D001711:Biotransformation; D002175:Candida / Q000201:enzymology*; D002214:Capsules; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007848:Laurates / Q000737:chemistry* / Q000378:metabolism; D008049:Lipase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D002214:Capsules; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D007848:Laurates; C050014:4-nitrophenyl laurate; D008049:Lipase