Levan versus fructooligosaccharide synthesis using the levansucrase from Zymomonas mobilis: effect of reaction conditions

This work addresses the effect of sucrose concentration and temperature on the three activities displayed by the levansucrase from Zymomonas mobilis: formation of levan (polymerization), production of short-chain fructooligosaccharides (FOS), and sucrose hydrolysis. Of the conditions tested, levan f...

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Detalles Bibliográficos
Autores: Santos-Moriano, Paloma, Fernández Arrojo, Lucía, Poveda, Ana, Jiménez-Barbero, Jesús, Ballesteros Olmo, Antonio, Plou Gasca, Francisco José
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/128244
Acceso en línea:http://hdl.handle.net/10261/128244
Access Level:acceso abierto
Palabra clave:Levan
Transfructosylation
Glycosidases
Enzymes
Prebiotics
Fructooligosaccharides
Biopolymers
Carbohydrates
Descripción
Sumario:This work addresses the effect of sucrose concentration and temperature on the three activities displayed by the levansucrase from Zymomonas mobilis: formation of levan (polymerization), production of short-chain fructooligosaccharides (FOS), and sucrose hydrolysis. Of the conditions tested, levan formation reached the highest value at 4ºC and 100 g/L sucrose. The increase of temperature (40ºC) and sucrose concentration (600 g/L) caused a significant decrease of the levan concentration and a higher production of FOS. However, an increase of the temperature also caused an enhancement of the undesired hydrolytic activity. Several inulin-type FOS (1-kestose, nystose, 1F-fructosylnystose), neoFOS (blastose, neokestose, neonystose) and levan-type FOS (6-kestose, 6,6-nystose) were synthesized by levansucrase. The latter compound was purified and characterized by mass spectrometry and 2D NMR. Using 600 g/L sucrose at 40°C, the maximum yield of FOS was reached at 85% sucrose conversion; at this point, the reaction mixture contained (in weight basis) 31% glucose, 14% fructose, 15% sucrose and 40% FOS (including a small contribution of levan).