Effect of anion on the interaction of carvacrol with imidazolium-based amino acid ionic liquids: Molecular dynamics simulations

Amino acid ionic liquids (AAILs) are applied for extracting and purifying carvacrol (CAR) due ‎to their biodegradability . This study investigates the solubility of CAR in AAILs using molecular ‎dynamics simulation. 1-methyl-3-propyl-imidazolium ([PMIM] + ) cation and amino acid anions ‎including alaninate , cysteinate, glycinate , and serinate were applied. The diffusion coefficient ‎values demonstrate that the lowest diffusion coefficient of CAR is observed in [PMIM][ALA] ‎indicating greater involvement of CAR. By examining the root-mean-square-deviation and the ‎movement path of CAR during the simulation time, it was found that the lowest fluctuation ‎and displacement of CAR occur in this green solvent . The anion-CAR interaction is stronger than the ‎cation-CAR interaction, with the oxygen atom of the carboxyl group of the anion and the ‎hydrogen atom of the hydroxyl group of CAR establishing the strongest interaction. The ‎probability of the presence of anion around CAR is the greatest in [PMIM][ALA] at a distance ‎of approximately 1.6 Å.‎ • Carvacrol as an anti-cancer can be extracted by green amino acid ionic liquids (AAILs) solvents. • Molecular dynamics simulation highlights AAILs ability to solubilize the carvacrol . • [PMIM][ALA] AAIL indicates the greatest involvement of carvacrol. • Spatial distribution functions demonstrate the presence of anion around carvacrol.