Preparation and Characterization of Carrageenan/Gelatin Microcapsules with the Addition of Essential Oil ^†

Encapsulation consists in surrounding the encapsulated substance (core, nucleus, active substance) with walls and thus closing it in the resulting structure. Most often, this is done by coating with a thin film of polymer (single capsule) or placing the core substance in the produced polymer matrix (agglomerate) by occlusion and/or adsorption [1,2,3]. One of the methods of obtaining microcapsules is coacervation. In this paper, microcapsules based on κ-carrageenan and gelatin type A were prepared by coacervation. The microcapsules were enriched with essential oils such as citronella oil and cinnamon oil, which have antimicrobial properties, in order to obtain materials that inhibit the growth of microorganisms. After optimizing the microcapsule production process, they were applied to natural leather to create a new antibacterial, odorless, and environmentally safe leather material. The microcapsules containing the selected essential oil were applied to the leather material in a batch process using a padding technique using a laboratory padding machine with adjustable roller pressure. Next, the antimicrobial properties of the new leather materials were tested against two bacterial strains, E. coli and S. aureus, and two fungal strains, Aspergillus niger ATCC 6275 and Candida albicans ATCC 1023. Very good and effective microbiological and antifungal effects were achieved with just 10% of microcapsules in the bath.