Optimisation of Encapsulation by Complex Coacervation of Phenolic Compounds from Propolis with Triumfetta cordifolia Gum and Kinetic Study

Abstract

Phenolic compounds from propolis have pharmacological properties such as antioxidant, antidiabetic, antiulcer, anticancer. However, they are unstable and oxidize in contact with ultraviolet rays and humidity. In order to limit their oxidation, phenolic compounds need to be protected through a polymeric membrane. The aim of this work is to optimize the encapsulation of phenolic compounds from propolis by complex coacervation using a polymer matrix consisting of gelatin and a Cameroonian tropical gum named Triumfetta cordifolia. A second order regression using Central Composite Design (CCD) was used to determine the optimal conditions of encapsulation as follows: pH (X1) 4.2, gelatin concentration (X2) 54 % and active ingredient concentration (X3) 25 %. The use of Triumfetta cordifolia gum as an anionic polymer led to a considerable encapsulation rate of total polyphenols and flavonoids with the values of 85.75 % and 88.24 % respectively. Concerning the study of the release kinetic of phenolic compounds from propolis, it appeared that the zero-order model better fitted the release in the gastric environment with a high correlation coefficient of R2 = 0.99. While in the intestinal environment it was the first-order model which better explained their slowed diffusion into the solvent (R2= 0.97).