Inclusion complexes of rosmarinic acid and cyclodextrins: stoichiometry, association constants, and antioxidant potential

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Bruno Medronho (Author) Other; Artur J. M. Valente (Author) Other; Patrícia Costa (Author) FEUP; Anabela Romano (Author) Other

Journal

Title: Colloid and Polymer Science

Vol. 292 No. 4

Pages: 885-894

ISSN: 0303-402X

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 7 Citations

Scopus - 9 Citations

Associated Projects

LSRE-LCM - Laboratório de Processos de Separação e Reação - Laboratório de Catálise e Materiais

Other information

Authenticus ID: P-009-9QB

DOI: 10.1007/s00396-013-3124-5

Abstract (EN): The interaction between beta-cyclodextrin (beta-CD) and the polyphenol rosmarinic acid (RA) is here reported by H-1 NMR titration experiments. The formation of an aqueous soluble inclusion complex is confirmed and valuable information regarding mode of penetration of guest into beta-CD, stoichiometry, and stability of the complex is obtained. The analysis by the continuous variation method shows the undoubted formation of 1:1 beta-CD/RA complex. Additionally, the estimated apparent association constants reveal the importance of the asymmetry of the RA in the complexation; the incorporation of the catechol moiety closer to the carboxylic group is more favorable (K = 2,028 M-1) than from the other end of the RA molecule (K = 1,184 M-1). Finally, we have also investigated the antioxidant activity and storage stability of the beta-CD/RA complexed system; the presence of beta-CD was found to produce a remarkable enhancement on the antioxidant activity.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10