Aim: The emergence of nosocomial infections, which are mainly transmitted by contaminated instruments, there is an urgent need of a novel disinfecting agent, which can able to act by the novel method with less residual concentration. Evaluation of antibacterial activity of thymol-eugenol mixture for potential application as disinfectant agent.

Methods: The reference strains of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were used for the determination of bactericidal activity for possible disinfectant activity. Docking study with enoyl ACP reductase (FabI) of E. coli was also performed to elucidate the possible mechanism of bactericidal action.

Results: Thymol-eugenol mixture inhibited the growth of the bacterial organism on increasing the concentration and the activity becomes more enhanced on by further increasing the residence time. Furthermore, both thymol and eugenol were found as efficient ligand engaging the active site of enoyl ACP reductase (FabI) of E. coli with estimated free energy of binding of -5.19 kcal/mol and -4.73 kcal/ mol. The estimated inhibition constant of thymol and eugenol was also found in agreement with the excellent bioactivity, 156.07 uM and 343.24 uM, respectively.

Conclusions: The present study corroborated that, thymol-eugenol mixture efficiently inhibits the growth of bacterial organism which easily survive on the medical instruments and can act as potential disinfecting agent.