Unleashing Nature’s Defense: Potent Antimicrobial Power of Mediterranean
Ethyl Acetate Extracts against Oral Pathogens and Streptococcus mutans
Biofilms
Abstract
The increasing demand for alternatives to antibiotics against resistant
bacteria has led to research on natural products. Aim of this study was
to analyze the antimicrobial and antibiofilm activity of 16
Mediterranean herb extracts against representative oral microorganisms.
The production of ethyl acetate extracts and the assays were carried out
under established experimental conditions. The extracts were analyzed
using High Performance Thin Layer Chromatography (HPTLC). The minimum
inhibitory concentration (MIC) and minimum bactericidal concentration
(MBC) of the extracts from Achillea taygetea, Cistus creticus ssp.
creticus, Cistus monspeliensis, Lavandula stoechas, Mentha aquatica,
Mentha longifolia, Origanum vulgare, Phlomis cretica, Rosmarinus
officinalis, Salvia sclarea, Satureja parnassica, Satureja thymbra,
Sideritis euboea, Sideritis syriaca, Stachys spinosa, and Thymus
longicaulis were determined against eight typical oral bacteria and the
fungus Candida albicans. Microtiter plate test was conducted to evaluate
the antibiofilm activity against Streptococcus mutans. Overall, all
tested extracts efficiently suppressed the growth of obligate anaerobic
bacteria. The extracts exhibited moderate to high antibiofilm activity
comparable to that of chlorhexidine (CHX) against S. mutans.
Interestingly, R. officinalis and O. vulgare demonstrated the highest
antibacterial activity against oral bacteria. Additionally, R.
officinalis and L. stoechas significantly inhibited S. mutans biofilm
formation at 0.15 mg / ml. Parvimonas micra showed high susceptibility
to R. officinalis, while C. albicans was sensitive to the O. vulgare
extract with a minimal fungicidal concentration (MFC) of 2.50 mg / ml.
These results suggest that the investigated plant extracts can be
considered as alternative natural antimicrobial and antibiofilm agents
against infectious oral diseases.