Inclusion complexes of flavonoids with propylenediamine modified β-cyclodextrin:Preparation, characterization and antioxidant

Abstract Inclusion complexes of three flavonoids including taxifolin (TFL), quercetin (QCT) and morin hydrate (MH) with propanediamine-β-cyclodextrin (DP-β-CD) were prepared by saturated aqueous solution method. Formation of the complexes were characterized by SEM, FT-IR, XRD, 1 HNMR and 2D NMR (ROESY). The UV-Spectrometric titration method indicated that DP-β-CD can form 1:1 inclusion complexes with TFL, QCT and MH, and the stability constants were 585.7, 209.9 and 1419.2 M -1 , respectively. The molecular modelling demonstrated the most stable inclusion model of three complexes. The water solubility of TFL, QCT and MH was increased 70–102 times after resulting inclusion complex with DP-β-CD. In addition, the antioxidant activity of DP-β-CD/TFL complex is better than that of TFL. This satisfactory water solubility and high antioxidant activity of the DP-β-CD/flavonoids complexes, will be potentially useful for their application as herbal medicine or healthcare products.