ARTÍCULO

Sorption and release of natural phenolic antioxidants in different cyclodextrin polymers

Autores: García-Padial Alonso, Marcos; Martínez Oharriz, María Cristina; Isasi Allica, José Ramón; Zornoza Cebeiro, María Arántzazu (Autor de correspondencia)
Título de la revista: JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
ISSN: 0021-8561
Volumen: 65
Número: 24
Páginas: 4905 - 4910
Fecha de publicación: 2017
Resumen:
The sorption and release of tyrosol and caffeic acid, two biophenolic antioxidants with known health benefits, in different insoluble cyclodextrin polymers have been studied. Cyclodextrin polymers were synthesized by cross-linking, beta-cyclodextrin or 50:50 w/w nominal mixtures of alpha- and beta-cyclodextrins using either epichlorohydrin (EP) or toluene-2,4-diisocyanate (TDI) as cross-linking agents. An analogous sucrose polymer was prepared using EP as cross-linking reagent. Freundlich isotherms and isosteric heats of sorption for tyrosol and caffeic acid in the insoluble beta-cyclodextrin polymer cross-linked with epichlorohydrin at 50 degrees C were obtained and discussed. Finally, the release of tyrosol and caffeic acid has been studied from loaded polymer disks, the microstructures of which were characterized by mercury intrusion porosimetry. Caffeic acid shows greater affinity than tyrosol for the polymeric matrices as it presents a higher sorption and a lower and slower release. However, tyrosol has a higher isosteric heat of sorption for low coverages.