Coencapsulation of Ferulic and Gallic acid in hp-b-cyclodextrin

The complexes formed by two polyphenols, trans-Ferulic acid (FA) and Gallic acid (GA) with 2-hydroxypropyl-b-cyclodextrin (HP beta CD), by the spray-drying method, were studied. Encapsulation-efficiencies (EE) of the complexes prepared were evaluated by HPLC. In the case of co-encapsulation, the EE of GA was lowered, whereas that of FA was almost stable, indicating a possible antagonistic relationship between the two phenols for the HP beta CD cavity. The physicochemical characterization of the complexes was carried out by Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). SEM observations revealed that the coencapsulated phenolic complex resulted in a more rounded shape outer surfaces of HP beta CD than when encapsulated separately. FT-IR and DSC data indicated that the two polyphenols exhibit a possible interaction in the coencapsulated complex. The complexes showed no loss of their ability to scavenge DPPH radical relatively to the single agent at the concentrations used. (C) 2015 Published by Elsevier Ltd.