Beet sugar syrup and molasses as low-cost feedstock for the enzymatic production of fructo-oligosaccharides

Sugar syrup and molasses from beet processing containing 620 and 570 mg/ml sucrose, respectively, were assayed as low-cost and available substrates for the enzymatic synthesis of fructo-oligosaccharides (FOS). A commercial pectinase (Pectinex Ultra SP-L, from Aspergillus aculeatus) characterised by...

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Detalles Bibliográficos
Autores: Ghazi, Iraj, Fernández Arrojo, Lucía, Gómez de Segura, María Aránzazu, Alcalde Galeote, Miguel, Plou Gasca, Francisco José, Ballesteros Olmo, Antonio
Tipo de recurso: artículo
Fecha de publicación:2006
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/10026
Acceso en línea:http://hdl.handle.net/10261/10026
Access Level:acceso abierto
Palabra clave:Prebiotics
Fructosyltransferase
Enzyme immobilization
Fos
Nutraceuticals
Fructofuranosidase
Descripción
Sumario:Sugar syrup and molasses from beet processing containing 620 and 570 mg/ml sucrose, respectively, were assayed as low-cost and available substrates for the enzymatic synthesis of fructo-oligosaccharides (FOS). A commercial pectinase (Pectinex Ultra SP-L, from Aspergillus aculeatus) characterised by the presence of a transfructosylating activity, was used as biocatalyst. The FOS production increased when lowering the initial pH value of syrup (7.5) and molasses (8.9) to 5.5. Sugar syrup and molasses were diluted in order to reduce substrate viscosity; interestingly, the percentage of FOS with regards to total sugars remained almost constant, which indicated a high transferase to hydrolase ratio for this enzyme. Kinetics of FOS production was analysed. Using approx. 10 U transfructosylating activity per g sucrose, the FOS concentration reached a maximum of 388 mg/ml after 30 h using syrup and 235 mg/ml in 65 h with molasses. These values corresponded to approx. 56% and 49% (w/w), respectively, of the total amount of carbohydrates in the mixture. The enzyme was also covalently immobilised on an epoxy-activated polymethacrylate-based polymer (Sepabeads EC-EP5). We found that immobilised Pectinex Ultra SP-L can be efficiently applied to the synthesis of FOS using syrup and molasses as substrates.