Aggregation of t10,c12 conjugated linoleic Acid in presence of natural and modified cyclodextrins. A physicochemical, thermal and computational analysis.

In this work the aggregation behavior of t10,c12 Conjugated linoleic acid (t10,c12-CLA) is presented for first time. The results show a c.m.c. of 25μM at pH 8 and 25°C. The encapsulation process with cyclodextrins (CDs) presented a 1:1 stoichiometry in all cases studied but the complexation constants were strongly dependent on the type of CDs used, the pH and temperature. Hydroxypropyl-beta-Cyclodextrin (HPβCD) was the best CD studied for encapsulating t10,c12-CLA. The resulting t10,c12-CLA-HPβCD complex showed a very high dependency on pH, which explains why a pK of 4.08 was found for first time, which was very close to the simulated value. Furthermore, the effect of temperature on the t10,c12-CLA-HPβCD was studied. The complexation constant (K) showed an increase behavior with the temperature. In addition, molecular docking calculations provided further insights into how the different interactions influence the complexation constant. Finally, a comparative study with rumenic acid, an isomer, was carried out.