Investigation of Antimicrobial Activity of Encapsulated Essential Oils

Antimicrobial activity of essential oils obtained from many plants has been known for a long time. However, the use of essential oils as active components of biomedical textile have recently gained popularity and aroused scientific interest. The antimicrobial activity of two essential oils, Rosmarinus officinalis and Abies sibirica, respectively, was detected using two indicator strains: Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922, respectively. To achieve a controlled release of antimicrobial activity and to enable utilization of higher concentrations of active ingredient, the essential oils were first encapsulated in beads based on alginate, gelatin and yeast cells, and then bounded to medical textile. The maximum oil content (85.4%) was achieved in alginate capsules. The release of essential oils was followed by determination of viable bacterial cells during a seven-day incubation of beads in saline. Rosmarinus officinalis and Abies sibirica immobilized in the beads showed a significantly prolonged activity, with some gel-dependent variation.