Artículo de revista
Spectroscopic characterization of the inclusion complexes of luteolin with native and derivatized β-cyclodextrin
Fecha
2010Registro en:
Bioorganic and Medicinal Chemistry, Volumen 18, Issue 14, 2018, Pages 5025-5031
09680896
10.1016/j.bmc.2010.05.079
Autor
Jullian Matthaei, Carolina
Cifuentes, Constanza
Alfaro, Muriel
Miranda, Sebastián
Barriga, Germán
Olea Azar, Claudio
Institución
Resumen
The inclusion complexes of Luteolin (LU) with cyclodextrins (CDs) including β-cyclodextrin (βCD), hydroxypropyl-β-cyclodextrin (HPβCD) and dimethyl-β-cyclodextrin (DMβCD), Scheme 1, have been investigated using the method of steady-state fluorescence. The stoichiometric ratio of the three complexes was found to be 1:1 and the stability constants (K) were estimated from spectrofluorometric titrations, as well as the thermodynamic parameters. Maximum inclusion ability was obtained in the case of HPβCD followed by DMβCD and βCD. Moreover, 1H NMR and 2D NMR were carried out, revealing that LU has different form of inclusion which is in agreement with molecular modeling studies. These models confirm that when LU-βCD and LU-DMβCD complexes are formed, the B-ring is oriented toward the primary rim; however, for LU-HPβCD complex this ring is oriented toward the secondary rim. The ESR results showed that the antioxidant activity of luteolin was the order LU-HPβCD > LU-DMβCD > LU-βCD > LU, hence