Determination of the inclusion complex constant between oleuropein and cyclodextrins by complexation theory

• Tipo: Artigo em Revista Científica Internacional
• Data: 2014

Autores

Carlos Eduardo Barao (Autor) Outra; Fatima Paiva Martins (Autor) FCUP; Gisella Maria Zanin (Autor) Outra; Flavio Faria De Moraes (Autor) Outra

Revista

Título: Journal of Inclusion Phenomena and Molecular Recognition in Chemistry

Vol. 78

Páginas: 465-470

ISSN: 0923-0750

Editora: Kluwer Academic Publishers

Indexação

ISI Web of Knowledge - 2 Citações

Scopus - 5 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-009-B4P

DOI: 10.1007/s10847-013-0318-x

Abstract (EN): Oleuropein (OLE) is a major phenolic compound of olive leaf (Olea europaea) and has many therapeutic properties associated with olive leaf extracts. This work concerns the determination of the inclusion complex constant between OLE and cyclodextrins (CDs), based on the competition of two guests for the CD cavity, one being a dye and the other OLE. The dye used was methylorange (MO) and pH 3 was selected, since MO molar absorptivity at 500 nm is at maximum in this condition. A solution of MO, OLE, and alpha-CD or beta-CD, with citrate buffer was used for determining the absorbance values. From these data and by appropriate mathematical modeling, the equilibrium constant for the formation of OLE: CD complexes were obtained: for OLE:alpha-CD K = 1,352.4 L mol(-1) (R-2 = 0.9975) and for OLE:beta-CD K = 1,827.9 L mol(-1) (R-2 = 0.9991). The results show that OLE has a greater affinity for beta-CD than for alpha-CD and given the relatively high constants, OLE:CD complexes have potential for giving longer shelf lives for OLE medicinal and food additive preparations.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6