Cosmetic and food products containing water are prone to contamination during the production, storage, and transit process, leading to product spoilage and degraded organoleptic characteristics. The efficient preservation of food and cosmetics is one of the most important issues the industry is facing today. The use of nanotechnology in food and cosmetics for preservation purposes offers the possibility to boost the activity of antimicrobial agents and/or promote their safer distribution into the end product upon incorporation into packaging or film constructions. In this review, current preservation strategies are discussed and the most recent studies in nanostructures used for preservation purposes are categorized and analyzed in a way that hopefully provides the most promising strategies for both the improvement of product safety and shelf-life extension. Packaging materials are also included since the container plays a major role in the preservation of such products. It is conclusively revealed that most of the applications refer to the nanocomposites as part of the packaging, mainly due to the various possibilities that nanoscience offers to this field. Apart from that, the route of exposure being either skin or the gastrointestinal system involves safety concerns, and since migration of nanoparticles (NPs) from their container can be measured, concerns can be minimized. Conclusion: Nanomaterial science has already made a significant contribution to food and cosmetics preservation, and rapid developments in the last years reinforce the belief that in the future much of the preservation strategies to be pursued by the two industries will be based on NPs and their nanocomposites.

A herbal mouthwash containing essential oils of holy basil and mountain tea, extracts of St John’s wort and European goldenrod (Bucovia™) and cetylpyridinium chloride, was developed and in vitro tested for its efficiency against biofilm formation by Streptococcus mutans, together with its eradicating activity against already preformed (48 h with saccharose) streptococcal biofilm. The minimum inhibitory (MIC) and bactericidal concentrations (MBC) of the final formulation, as well as of its individual components, were initially determined. The results revealed that the mouthwash needed to be applied at two-times its MIC (0.63% v.v⁻¹) to completely inhibit biofilm formation by S. mutans, which was otherwise capable of developing a robust biofilm on the tested surface. Once fully developed, the matrix of the biofilm was found to contain a significant amount of exopolysaccharides protecting the cells, being impossible to eradicate even when exposed to pure mouthwash for 15 min, highlighting the great recalcitrance of biofilm-embedded S. mutans. Graphical Abstract