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Despite several decades of research into encapsulation of bacteria, most of the proposed technologies are in the form of immobilized cultures. In this work, sporopollenin exine capsules (SECs) opened, using silica particles which act as pressing micro‐probes, and loaded with Lactobacillus casei (L. casei) cells, are described for the first time. The proposed encapsulation provided ≈30× higher encapsulation yield (30.87%), compared to direct compression of SECs (0.99%). Encapsulated L. casei cells show 1.21‐ and 2.25‐folds higher viability compared to free cells, in in vitro simulated fasted and fed media representing the human gastrointestinal (GI) tract, respectively. Encapsulated L. casei can proliferate inside the SECs, generating enough pressure to cause the SECs to burst and release the viable and metabolically active cells. The noticeable difference with the application of the SECs as a means of encapsulation is that the SECs may act as a bioreactor and provide time for the encapsulated cells to multiply thousands of times before being released, following the SEC's burst. The unique advantages of SECs alongside the proposed encapsulation method, demonstrates the potential application of SECs as delivery system of probiotics to the distal part of the human GI tract.

Propolis ethanolic extracts (PE) are rather complicated mixtures of bioactive compounds belonging to several chemical classes. The potential use of beta-cyclodextrin (beta-CD) cavity for the incorporation of specific PE components, aiming to increase their solubility in water, was studied in a Greek propolis, which was rich in polyphenols and terpenes. The PE/beta-CD inclusion complexes were prepared by sonication of PE suspensions in aqueous solutions of beta-CD, followed by filtration and freeze-drying. The aqueous solubility of PE in the presence of beta-CD was studied by the construction of solubility diagrams and by determining the fraction of PE constituents that was dissolved in water. Encapsulation efficiencies were found to be higher (9.4-23.3%) for relatively small aromatic molecules like cinnamic and benzoic acid derivatives and lower for terpenic acids (5.0-6.7%), anthraquinones (3.6-8.4%) and flavonoids (4.0-10.7%). The respective in vitro solubilities in simulated gastric fluid followed an opposite trend, being lower for the relatively small aromatic molecules. It is concluded that the encapsulation in beta-CD may increase the solubility of PE constituents in a manner related to their structure, while the amount of substances released will depend both on their chemical properties and on their relative abundance in the matrix.