title: Physicochemical aspects of lipase B from Candida antarctica in bicontinuous microemulsions.
abstract: Biotechnology involves applying enzymes in organic synthesis to convert non-natural substrates into enantiomerically pure products under mild reaction conditions. Non-natural substrates are often lipophilic molecules that can hardly be accessed and converted by enzymes in their natural aqueous environment. Bicontinuous microemulsions provide a spongelike nanostructure with a large interfacial area between aqueous and oil domains, which makes them valuable alternative reaction media. In the present study, we introduced lipase B from Candida antarctica into a bicontinuous microemulsion of composition H2O/NaCl-n-octane-pentaethylene glycol monodecylether (C10E5). Phase behavior, partitioning studies, and pulsed-field-gradient NMR measurements revealed that the lipase is mostly adsorbed at the microemulsions interface. Phase diagrams showed a maximum in efficiency with increasing amount of lipase added to the water phase of the microemulsion. It was observed that the ratio between the mass of lipase that is introduced into the system and the mass of lipase that is located at the interface stays constant. Self-diffusion coefficients of all components showed that the presence of the lipase is not influencing the bicontinuity of the microemulsion.
authors.affiliation: Institut für Physikalische Chemie, Universität Stuttgart , Pfaffenwaldring 55, 70569 Stuttgart.
authors.forename: Mireia
authors.initials: M
authors.lastname: Subinya
authors.forename: Anne K
authors.initials: AK
authors.lastname: Steudle
authors.forename: Bettina
authors.initials: B
authors.lastname: Nestl
authors.forename: Bernd
authors.initials: B
authors.lastname: Nebel
authors.forename: Bernhard
authors.initials: B
authors.lastname: Hauer
authors.forename: Cosima
authors.initials: C
authors.lastname: Stubenrauch
authors.forename: Sandra
authors.initials: S
authors.lastname: Engelskirchen
mesh_terms: D055598:Chemical Phenomena; D004058:Diffusion; D004655:Emulsions; D004987:Ethers / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D008049:Lipase / Q000737:chemistry* / Q000378:metabolism; D009795:Octanes / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D004655:Emulsions; D004987:Ethers; D005656:Fungal Proteins; D009795:Octanes; D014867:Water; C077053:pentaethylene glycol monododecyl ether; D011092:Polyethylene Glycols; D012965:Sodium Chloride; D008049:Lipase; C431349:lipase B, Candida antarctica; C026728:octane