Efficient α-glucosylation of epigallocatechin gallate catalyzed by cyclodextrin glucanotransferase from Thermoanaerobacter sp.

The glycosylation of plant polyphenols may modulate their solubility and bioavailability, and protect these molecules from oxygen, light degradation and during gastrointestinal transit. In this work, the synthesis of various α-glucosyl derivatives of (‒)-epigallocatechin gallate (EGCG), the predomin...

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Detalles Bibliográficos
Autores: González-Alfonso, José L., Leemans, Laura, Poveda, Ana, Jiménez-Barbero, Jesús, Plou Gasca, Francisco José
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/167290
Acceso en línea:http://hdl.handle.net/10261/167290
Access Level:acceso abierto
Palabra clave:Glycosylation
Tea polyphenols
Antioxidants
Catechins
Cyclodextrin glucosyltransferase
Enzymatic glucosylation
Descripción
Sumario:The glycosylation of plant polyphenols may modulate their solubility and bioavailability, and protect these molecules from oxygen, light degradation and during gastrointestinal transit. In this work, the synthesis of various α-glucosyl derivatives of (‒)-epigallocatechin gallate (EGCG), the predominant catechin in green tea, was performed in water at 50 °C by a transglycosylation reaction catalyzed by cyclodextrin glycosyltransferase (CGTase) from Thermoanaerobacter sp. The molecular weight of reaction products was determined by HPLC-MS. Using hydrolyzed potato starch as glucosyl donor, two main monoglucosides were obtained with conversion yields of 58% and 13%, respectively. The products were isolated and chemically characterized by combining 2D-NMR methods. The major derivative was epigallocatechin gallate 3’-O-α-D-glucopyranoside (1) and the minor epigallocatechin gallate 7-O-α-D-glucopyranoside (2).