Caracterização de microencapsulados contendo própolis vermelha de Alagoas obtidos por gelificação iônica

Abstract

Propolis is a natural product that presents a complex mixture, formed by a resinous and balsamic material collected by bees from branches, flowers, pollen, buds and tree exudates. In Brazilian territory, red propolis can be found in several parts of the coast, mainly in mangrove areas. With Dalbergia ecastophyllum as its botanical origin, popularly known as “rabo-debugio”, Red Propolis from Alagoas stands out for presenting a large number of flavonoids, phenolic compounds and some other exclusive compounds. These bioactive compounds have several biological activities, such as anti-inflammatory, healing, antioxidant, antimicrobial, antiviral potential, antifungal, anticancer, immunomodulatory, among others. In this study, we developed microcapsules (beads) containing crude red propolis extract (5%), from the ionic gelation method using sodium alginate (1% e 2%) and calcium chloride (CaCl2), in different concentrations. Subsequently, the generated beads were characterized by scanning electron microscopy (SEM), revealing diameters between 330 and 337 µm for the microspheres, characterizing the best formation. Then, this was analyzed by Fourier transform infrared spectrophotometry using attenuated total reflectance (FTIR-ATR), where typical stretching of CO, C=C, C–H and O–H, compatible with structures present in the sample. Thermogravimetry (TG) showed three loss events from the sample, accounting for 15, 46 and 10% weight loss, respectively. Differential scanning calorimetry (DSC) showed exothermic events for the sample, compatible with an amorphous material. Subsequently, the beads showed good solubility in an aqueous solution containing a mixture of EDTA and sodium citrate (2% w/v) after 24h.Then, high-performance liquid chromatography with diode array detector (HPLCDAD) was able to identify and quantify seven PVA constituents in the most promising formulation, namely liquiritigenin, daidzein, pinobanksin, isoliquiritigenin, formononetin, pinocembrin and biochanin A. Finally, the beads produced proved to be stable. From the results obtained, the beads containing PVA may have biological applicability against different pathogens, or even contribute to advances in the food industry.