Microencapsulation of olive oil by Poly-hydroxy-butyrate-co-valerate / Polyethylene glycol

Abstract

Encapsulation is a technology widely used in the industrial field because it brings many advantages, especially in the pharmaceutical field. Among the existing microencapsulation techniques, microencapsulation by solvent evaporation in simple emulsion remains one of the most used for hydrophobic active ingredients because it does not require specific equipment and uses mild operating conditions (temperature and ambient pressure generally). Which was the subject of our present study which targets to encapsulation the olive oil by polyhydroxy (butyrate-co-valerate) PHBV using the method of evaporation of the organic solvent which is chloroform. The encapsulation yields obtained with respect to the different parameters are between 66 and 80 %, the best of which is obtained with the highest amount of active ingredient, which is 0.4 g/ml. Microscopy allowed us to observe the morphology of the powders obtained, where the latter are in the form of a powder (spherical) and other are aggregates. The macroscopic and microscopic analysis showed that the increase of the emulsion agitation speed, the amount of surfactant percentage and the nature of the latter, allow to modify the size of the microparticles, which has been proved, in agreement with the theory. The FTIR analysis showed the presence of olive oil in the PHBV microparticles, and highlighted the absence of chemical interactions between the polymers and olive oil. Thermal analysis by thermogravimetry confirmed the existence of olive oil in the PHBV microparticles by the presence of two losses of mass, first in the interval (200 to 250) which corresponds to the degradation of oil and another loss after this range of (250 to 400) attributed to the decomposition of the encapsulant (PHBV).