Effectiveness of B12N12 Nanocage as a Stabilizer and Delivery Carrier for Thymol and Carvacrol Essential Oils and their Influence on Escherichia coli and Staphylococcus aureus Bacteria: A Comprehensive Analysis using DFT, QTAIM, Multiwfn, and Molecular Docking

Abstract

Bacteria have developed a tolerance due to the overuse of antibiotics. Even though thyme essential oils have antibacterial properties, their utilization is restricted because of their instability. To overcome these limitations, one strategy is to interact the oils with other molecules. This research delved into the effective role of B₁₂N₁₂ in attaching thymol and carvacrol oils as a nanocarrier in drug delivery using density functional calculations (DFT) in both gas and solvent phases. Thymol and carvacrol oils have been found to interact with B₁₂N₁₂ through oxygen atoms, resulting in adsorption energies (E_ad) of –12.49 and –12.39 kcal/mol on the nanocage, respectively. The adsorption and solvation energy values, along with notable alterations in the polarity of the complexes, indicated the potential of the B₁₂N₁₂ nanocage as an effective delivery carrier for the oils. The analysis of the quantum theory of atoms in molecules (QTAIM), the electron localization function (ELF), localized orbital locator (LOL), and density of states (DOS) showed that the nature of the interaction between the oils and the nanocage is non-covalent, which is beneficial for the release of the oils in drug delivery. The quantum molecular descriptors (QMDs) and the vibrational frequency calculations indicated that the complexes are stable. Moreover, Mulliken population analysis (MPA), molecular electrostatic potential (MEP), UV-Vis spectra, and thermodynamic parameters for the molecules were calculated. In silico molecular docking, 4WUB and 3VSL receptors were used to investigate thymol, carvacrol, thymol/B₁₂N₁₂, and carvacrol/B₁₂N₁₂ compounds inhibitor properties. The molecular docking analysis showed that the thymol/B₁₂N₁₂ and carvacrol/B₁₂N₁₂ compounds have the free negative binding energy values and low Ki (inhibition constant) values. This suggests that these compounds are more suitable for interacting with the 4WUB and 3VSL receptor targets compared to the Thymol and Carvacrol oils.