16Recently there has been an increased interest towards the biological activities of essential oils 17 (EOs). However, EOs are unstable and susceptible to degradation when exposed to 18 environmental stresses like oxygen, temperature, and light. Therefore, attempts have been 19 made to preserve them through encapsulation in various colloidal systems such as 20 microcapsules, nanospheres, nanoemulsions, liposomes, and molecular inclusion complexes. 21 This review focuses on various techniques used for the encapsulation of EOs, potential 22 applications in food, and their behaviours/trends after encapsulation. The encapsulation 23 efficiency, particle size, and physical stability of EOs encapsulated in colloidal systems is 24 dependent on the kind of technique and the type and concentration/ratio of emulsifier/wall 25 material used. Moreover, the benefits associated after encapsulation, namely bioavailability, 26 controlled release, and protection of EOs against environmental stresses are discussed. The 27 applications of encapsulated EOs are also summarized in this review. Encapsulated EOs are 28promising agents that can be used to increase the anti-microbial, antifungal, antiviral, and 29 pesticidal activities of EOs in real food systems, to study their action mechanism, and to 30 provide nonlethal therapeutic agents to treat several diseases. 31

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Hyperosmotic agents such as maltodextrin negatively impact bacterial growth through osmotic stress without contributing to drug resistance. We hypothesized that a combination of maltodextrin (osmotic agent) and vancomycin (antibiotic) would be more effective against Staphylococcus aureus biofilms than either alone. To test our hypothesis, S. aureus was grown in a flat plate flow cell reactor. Confocal laser scanning microscopy images were analyzed to quantify changes in biofilm structure. We used dissolved oxygen microelectrodes to quantify how vancomycin and maltodextrin affected the respiration rate and oxygen penetration into the biofilm. We found that treatment with vancomycin or maltodextrin altered biofilm structure. The effect on the structure was significant when they were used simultaneously to treat S. aureus biofilms. In addition, vancomycin treatment increased the oxygen respiration rate, while maltodextrin treatment caused an increase and then a decrease. An increased maltodextrin concentration decreased the diffusivity of the antibiotic. Overall, we conclude that (1) an increased maltodextrin concentration decreases vancomycin diffusion but increases the osmotic effect, leading to the optimum treatment condition, and (2) the combination of vancomycin and maltodextrin is more effective against S. aureus biofilms than either alone. Vancomycin and maltodextrin act together to increase the effectiveness of treatment against S. aureus biofilm growth.