Desenvolvimento, caracterização e estudos de dissolução de microencapsulados poliméricos de liberação controlada de extrato de própolis vermelha obtidos através da técnica de secagem Spray Drying

Abstract

Red propolis is an emerging natural product because its complex chemical composition is rich in phenolic compounds with antioxidant, antimicrobial and anti-inflammatory activity. Although propolis has several biological activities, its solubility and sensory characteristics as a bitter taste, reduce its consumption by the potential consumers. Microencapsulation of the compounds by spray drying is a strategy in which the bioactives are coated with a mixed layer of biopolymers, which gives the product the desired pharmaceutical characteristics such as release control, dissolution of active substances, reduction in the number of daily doses and improve sensory characteristics, contributing to treatment effectiveness. Arabic and xanthan gums, maltodextrin and starch, are currently one of the materials of greatest interest for applicability in the medical and pharmaceutical fields due to the high solubility in water, film forming capacity and high physical stability and their environmental impact is lower due to low energy consumption involved in its production and its status as a renewable resource. The objective of this work was to develop and characterize two formulations of red-propolis spray-dryer microencapsulates using the aforementioned biopolymers and to evaluate the compatibility and flavonoid release profile of propolis in biopolymer matrices. The red propolis extract was incorporated into the biopolymer solution, and then submitted to spray drying, obtaining microencapsulations that were submitted to morphology (SEM), thermal analysis (TG and DSC) and FTIR for the purpose of evaluate the stability and confirm microencapsulation of the extract and flavonoid dissolution profile release tests over a period of 12 hours in different media (water, acid-buffer, buffer and acid). The microparticles observed in SEM showed spherical morphology with sizes between 2.5 and 35 μm, with no apparent porosity, revealing the integrity of the wall of the microparticles. The thermal analysis showed that the wall material decelerates the thermo-oxidative degradation of the extract in the microencapsules and according to the calorimetric curves (DSC) and infrared spectra there was microencapsulation of the extract. The quantification of the bioactive compounds showed high efficiency of the microencapsulation, preserving the phenolic compounds and the potential of the antioxidant activity of the ethanolic extract. Finally, the dissolution profile showed that the microencapsules have controlled release in 12 hours in the different media, being highly soluble in water and buffer 6,8.