Antibacterial activity of three construction coatings containing Rosemary and Eucalyptus essential oils against Pseudomonas aeruginosa

Abstract

Essential oils are natural volatile compounds, widely used in health-care practices. An extensive variety of plants have been globally discovered and utilized for the extraction of essential oils because of their activities against bacterial pathogens. In the present study, the antimicrobial activities of Rosemarinus officinalis and Eucalyptus camaldulnesis essential oils alone and combined with three different types of building coatings; acrylic resin, polyurethane, and titanium dioxide were evaluated against Pseudomonas aeruginosa. GC and GC–MS analyses revealed twenty-one and Twenty-two compounds in the essential oils of R. officinalis and E. camaldulnesis, respectively. Antibacterial activities of the oils were screened using disc diffusion technique. The minimal inhibitory and bactericidal concentrations of the oils were assessed through macrodilution method. Although both essential oils had significant antibacterial activity (p < 0.001), Rosemary oil showed a relatively higher activity against P. aeruginosa growth. Practical efficiency of coatings in combination with essential oils was also evaluated, and it was found that the combination R. officinalis essential oil with titanium dioxide represents the highest antibacterial activity. Our results support that the essential oils from R. officinalis and E. camaldulnesis can be used in combination with building coatings in order to fight P. aeruginosa especially in hospitals.