Endodontic potential of eugenol against Enterococcus faecalis: Antibacterial, antibiofilm, and network pharmacology insights.

OBJECTIVE: The present study aimed to evaluate the antibacterial and antibiofilm efficacy of eugenol against clinical isolates of Enterococcus faecalis obtained from persistent root canal infections and to investigate its potential interactions with virulence-associated target proteins using network pharmacology and molecular docking approaches. METHODS: Clinical isolates of E. faecalis were recovered from infected root canal samples and identified using standard microbiological methods. Antibacterial activity of 2% and 4% eugenol was assessed using the agar disc diffusion assay, with further determination of MIC and MBC values using microbroth dilution method. Antibiofilm activity was evaluated using an ex vivo dentinal root canal biofilm model followed by CFU analysis. Potential molecular targets of eugenol were identified further using standard computational tools. RESULTS: 4% eugenol exhibited the largest zone of inhibition (23.4 ± 1.4 mm) with the MIC and MBC values at 0.04 mg/mL and 0.4 mg/mL, respectively. In the ex vivo biofilm model, 4% eugenol significantly reduced bacterial colony counts and demonstrated antibiofilm activity comparable to 2% CHX. Network pharmacology analysis identified five potential target proteins, namely pyrG, thyA, accD, tgt, and mtnN and the molecular docking demonstrated favorable binding interactions between eugenol and the selected targets. CONCLUSION: Eugenol demonstrated significant antibacterial and antibiofilm activity against E. faecalis and the computational analyses suggesting the potential interactions with virulence-associated proteins involved in important metabolic pathways. These findings indicate the potential of eugenol as a plant-derived antimicrobial candidate for endodontic applications; however, further in vivo and toxicity studies are required before clinical application.