Abstract
In light of the growing antibiotic resistance, the usage of plant-derived antimicrobial agents could serve as an effective alternative treatment against oral infections. The aim of this study was to investigate the antimicrobial and antibiofilm activity of Mediterranean herb extracts against representative oral microorganisms. The extraction procedures and the analysis of the obtained extracts were performed under established experimental conditions. The minimum inhibitory (MIC) and bactericidal (MBC) concentrations of the methanol extracts of Cistus creticus ssp. creticus, Cistus monspeliensis, Origanum vulgare, Rosmarinus officinalis, Salvia sclarea and Thymus longicaulis against eight typical oral bacteria and the fungus Candida albicans were determined. The antibiofilm activity against Streptococcus mutans was also quantified using the microtiter plate test. Overall, all tested extracts inhibited effectively the screened obligate anaerobic microorganisms and in concentrations ≥0.3 mg ml-1 had moderate to high antibiofilm activity comparable to that of chlorhexidine (CHX) against S. mutans. In particular, R. officinalis (MIC: 0.08–5.00 mg ml-1) and S. sclarea (MIC: 0.08–2.50 mg ml-1) showed the highest antibacterial activity, while Cistus spp., R. officinalis and S. sclarea significantly inhibited S. mutans biofilm formation at 0.60, 1.25 and 2.50 mg ml-1, respectively. Porphyromonas gingivalis and Parvimonas micra were high susceptible to O. vulgare (MIC = 0.30 mg ml-1), whereas T. longicaulis eradicated all oral bacteria (MBC: 0.15–2.50 mg ml-1). Nevertheless, C. albicans showed no sensitivity to the tested extracts. In conclusion, the tested plant extracts could serve as alternative natural antibacterial and antibiofilm components against oral infections.
Highlights
The statement of Hippocrates “Natural forces are the true healers of disease” reflects the fact that thousands of years before any synthetic medicaments were known, nature had been widely considered as the only limitless source of healing components
Phenolic acids and in particular rosmarinic acid appear as intense fluorescent blue spots in all four plant species (O. vulgare, R. officinalis, T. longicaulis and S. sclarea), while absorbance at 254 nm is typical of flavonoids
In this report all tested extracts effectively inhibited mainly the anaerobic oral microorganisms and in concentrations 0.3 mg ml-1 had moderate to high antibiofilm activity against S. mutans comparable to that of CHX
Summary
The statement of Hippocrates “Natural forces are the true healers of disease” reflects the fact that thousands of years before any synthetic medicaments were known, nature had been widely considered as the only limitless source of healing components. The ultimate intention has always been to use natural products with favorable antimicrobial, anti-inflammatory and antitumoral properties, without side effects at the chosen concentration, for medicinal purposes. We have seen diverse plant extracts as well as pure natural compounds as part of various treatment protocols in daily medicinal use [1,2,3,4,5]. Plant extracts originating from the Mediterranean area belong to the most frequently screened natural resources for application in medicine [6,7,8]. The two main components of Origanum vulgare, namely thymol and carvacrol, present synergistic activity against Streptococcus mutans, Streptococcus mitis, Prevotella oris, Prevotella intermedia, Micrococcus luteus and others [12, 13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
