Biofilm inhibition by biocompatible poly(?-caprolactone) nanocapsules loaded with essential oils and their cyto/genotoxicity to human keratinocyte cell line

Essential oils (EOs) of Thymus capitatus (Th) carvacrol chemotype and Origanum vulgare (Or) thymol andcarvacrol chemotype were encapsulated in biocompatible poly(?-caprolactone) nanocapsules (NCs). Thesenanosystems exhibited antibacterial, antifungal, and antibiofilm activities against Staphylococcus aureus,Escherichia coli, and Candida albicans. Th-NCs and Or-NCs were more effective against all tested strains than pureEOs and at the same time were not cytotoxic on HaCaT (T0020001) human keratinocyte cell line. The genotoxiceffects of EO-NCs and EOs on HaCaT were evaluated using an alkaline comet assay for the first time, revealingthat Th-NCs and Or-NCs did not induce DNA damage compared with untreated control HaCaT cells in vitro after24 h. The cells morphological changes were assessed by label-free live cell Raman imaging. This studydemonstrate the ability of poly(?-caprolactone) nanocapsules loaded with thyme and oregano EOs to reducemicrobial and biofilm growth and could be an ecological alternative in the development of new antimicrobialstrategies.