Nanoemulsion-based polyherbal mouthwash of cinnamon and clove oil: physicochemical characterization, molecular docking, and antimicrobial evaluations.

Objective: Different oils were used to develop nanoemulsion-based polyherbal mouthwashes (PHMs) of Cinnamon zeylanicum hydroalcoholic extract, and then their antibacterial activities against a range of oral pathogenic bacteria were assessed. Standard chlorhexidine acetate (CHD-A) was used as a control.

Methods: Different PHMs of C. zeylanicum extract based on nanoemulsions were obtained and the influence of various oils such as clove oil (CO), eucalyptus oil (EO), rose oil (RO), peanut oil (PO), and sesame oil (SO) on physicochemical and antibacterial characteristics of PHMs was studied. PHMs were characterized for the following parameters: droplet size, polydispersity index (PDI), refractive index (RI), transmittance (T), and pH. The optimized product was evaluated for size and shape on its surface using transmission electron microscopy (TEM).

Results: Nanoemulsion-based PHM prepared using CO showed the best physicochemical and antimicrobial properties compared to those prepared using EO, RO, PO, and SO. TEM investigation of an optimized formulation showed spherical-shaped droplets of formulation within the nanosize distribution of droplets. Against all oral infections, the antibacterial effects of the formulation made with CO (COPHM) were shown to be significantly greater than those of the formulation made with EO, RO, PO, and SO, as well as CHD-A. The formulation COPHM has been optimized as the final formulation based on minimum droplet size (31.41 nm), lowest PDI (0.141), ideal RI (1.336), highest %T (99.41), ideal pH (6.48), and largest antibacterial effects.

Conclusion: These results suggested the potential of nanoemulsion-based PHM in treating a range of diseases caused by oral pathogens.