Physico-chemical investigation on the interaction between ochratoxin A and heptakis-2,6-di- O-methyl--cyclodextrin
Abstract
The interaction of ochratoxin A (OTA) with heptakis-2,6-di-O-methyl-β-cyclodextrin (DIMEB) in aqueous solutions at two different pHs (3.5 and 9.5) was studied by means of spectroscopic, calorimetric and electrochemical techniques. DIMEB affected the physico-chemical properties of OTA. A stronger interaction was observed at pH = 3.5 where the neutral form of OTA prevails. The spectroscopic information indicated that the OTA/DIMEB inclusion process occurred through the insertion of the phenylalanine group into the cyclodextrin (CD) cavity; moreover, voltammetry experiments showed that the isocoumarinic phenolic group was also involved, probably by non-inclusion interactions. At pH = 3.5, binding constants and thermodynamic parameters of the OTA/DIMEB complex were determined by means of the modified Benesi-Hildebrand equation and van’t Hoff plot. A 1:1 stoichiometry for the OTA/DIMEB complex was observed with a binding constant equal to 530 ± 50 L·mol−1 at 25 °C. The calculated thermodynamic parameters indicate that the interaction is highly endothermic and that the complex formation is driven by entropy. The results provide useful information for potential applications of cyclodextrins in the analysis of mycotoxins and in the field of mycotoxin sequestering agents
Autore Pugliese
Tutti gli autori
-
LONGOBARDI F.;CATUCCI L.;COSMA P.
Titolo volume/Rivista
Non Disponibile
Anno di pubblicazione
2014
ISSN
0095-9782
ISBN
Non Disponibile
Numero di citazioni Wos
Nessuna citazione
Ultimo Aggiornamento Citazioni
Non Disponibile
Numero di citazioni Scopus
Non Disponibile
Ultimo Aggiornamento Citazioni
Non Disponibile
Settori ERC
Non Disponibile
Codici ASJC
Non Disponibile
Condividi questo sito sui social