Propolis is a lipophilic, sticky substance known for its strong biological activity. It has been used in medicine for centuries, but has limited use due to its strong taste and aroma, insolubility in water, and poor yield during processing. Most of its limitations can be omitted by encapsulation in various polysaccharide carriers, mainly using lyophilization and spray-drying. By optimizing the propolis extract encapsulation process, we obtained a water-soluble propolis powders/microparticles that do not contain organic solvents, have strong biological activity and good stability, while we also minimized losses during the procedure. Lyophilization proved to be the best method for encapsulation. In the following, we compared the activity of encapsulated samples with propolis extract. The results proved that both samples of propolis have good antioxidant properties, microparticles excelling in oil (sunflower, fish), and extract in liposomes. Propolis extract also displayed stronger antibacterial activity and had greater influence on the temperature of the phase transition of lipid bilayers. In order to prove the synergistic effects of compounds in propolis, we prepared mixtures of five selected polyphenols ((-)-epigallocatechin-3-gallate (EGCG), chrysin, quercetin, caffeic acid, trans-ferulic acid) and studied their influence on the bilayer. Some combinations displayed synergistic, while others displayed antagonistic effects. Finally, using microscopy, differential scanning calorimetry and isothermal titration calorimetry, we proved that the effect of EGCG on the temperature of the bilayer’s phase transition is the result of liposomal aggregation, which depends on the concentration of EGCG in the solution.
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