Abstract
Aim
Enterococcus faecalis is a significant pathogen in endodontic infections, often leading to treatment failure in root canal therapy and contributing to chronic infections. The growing concern over antimicrobial resistance highlights the need for alternative treatment approaches. This study aims to evaluate the antibacterial properties of aqueous green tea (Camellia sinensis) and peppermint (Mentha × piperita) extracts, focusing on their phytochemical profiles and antibacterial activity against E. faecalis, a major pathogen in endodontic infections.
Material and Methods
Phytochemical analysis of green tea and peppermint extracts was conducted to determine the content of key compounds, including tannins, flavonoids, hydroxycinnamic acid derivatives, and total polyphenols. The antibacterial activity of green tea and peppermint extracts, as well as their key compounds, (–)-epigallocatechin gallate (EGCG), (–)-epicatechin, caffeic acid, and rosmarinic acid, was assessed using the broth dilution method to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against E. faecalis clinical strains.
Results
Green tea extract showed superior antibacterial activity (MIC/MBC 1.25–2.5/5–10 mg mL−1), with EGCG exhibiting the highest efficacy (MIC/MBC 0.25–0.5/1 mg mL−1). Peppermint extract demonstrated moderate antibacterial activity, with its active compounds, caffeic acid and rosmarinic acid, showing higher MIC/MBC values. A 1:1 mixture of both extracts demonstrated antagonistic effects, yielding higher MIC and MBC values compared to the individual extracts.
Conclusions
The results suggest that green tea, particularly EGCG, holds significant potential for oral health applications due to its strong antibacterial activity against E. faecalis. The findings indicate that green tea could contribute to the effective treatment of E. faecalis-related infections, although the combination of green tea and peppermint extracts may not provide additive benefits.