Synergy of garlic extract and deep eutectic solvents as promising natural Antibiotics: Experimental and COSMO-RS

The growing concern of antibiotic resistance calls for the identification of new and sustainable solutions. In this study, we employed the COSMO-RS model to select promising deep eutectic solvents (DESs) for investigating the antibacterial properties of Allium sativum L. (garlic) extract. Through computational analysis, we selected two hydrogen bond acceptors (HBAs) and three hydrogen bond donors (HBDs) and found that DESs containing choline chloride (ChCl) as an HBA were the most optimal for this research. Our experiments revealed that the chosen mixtures, which consisted of 50 % garlic extract and 50 % DES, displayed outstanding activity against 11 microbial strains including gram-positive and gram-negative bacteria as well as a fungal strain commonly found in hospital settings with inhibition zones ranging from 18 to 50 mm. Notably, the selected mixtures displayed a synergistic effect against B. subtilis, S. aureus, and L. monocytogenes. Furthermore, the minimum inhibitory and minimum bactericidal concentrations (MIC and MBC) recorded were between 0.0125 and 0.4 µl/ml, respectively. These findings confirm the potent antibacterial properties of Allium sativum L. extract and the enhancement of its effectiveness when combined with DESs. This study represents a significant step towards the development of natural and sustainable alternatives to combat antibiotic resistance.