Evaluation of chemical composition and antimicrobial activities of Eucalyptus camaldulensis essential oil on dental caries pathogens

Introduction: Various microorganisms are involving in oral infections. Antimicrobial agents used against oral pathogens have side effects and can caused drug resistance. Eucalyptus is one of the most widely used plant with antimicrobial activity. Therefore, the aim of this study was to investigate the chemical composition and antimicrobial activity of Eucalyptus camaldulensis (E. camaldulensis) essential oil on dental caries pathogens includes Streptococcus mutans (S.mutans), Lactobacillus rhamnosus (L. rhamnosus), Actinomyces viscosus (A. viscosus), and Candida albicans (C. albicans). Materials and methods: In this study, E. camaldulensis essential oil was prepared and its antimicrobial activity was evaluated by disk diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods on stablished terminology strains of C. albicans, S. mutans, L. rhamnosus and A. viscosus. Moreover, chemical composition of E. camaldulensis essential oil was evaluated by gas chromatography-mass spectrometry (GC-MS) method. Results: Our results showed that the most antibacterial activity of E. camaldulensis essential oil was related to L. rhamnosus, A. viscosus, and S. mutans. Also, E. camaldulensis essential oil showed an appropriate antifungal activity against C. albicans. The dominant chemical composition of E. camaldulensis essential oil was 1,8-cineole (36.62%). Conclusion: In general, E. camaldulensis essential oil has an appropriate antifungal and antibacterial activity against oral pathogens. Therefore, it can be use in pharmaceutical industry to produce antimicrobial agents against dental caries and oral infectious diseases.