ChemistrySelect, cilt.11, sa.9, 2026 (SCI-Expanded, Scopus)
The emergence of antibiotic-resistant strains of Staphylococcus aureus underscores the urgent need for novel therapeutic strategies. This study evaluates the in vitro antibacterial, antioxidant, and cytotoxic properties of glycyrrhizic acid (GA) in combination with ciprofloxacin (CIP) against S. aureus ATCC 25923. Antimicrobial activity was determined using broth microdilution and checkerboard assays, revealing MIC values of 0.25 µg/mL for CIP and 512 µg/mL for GA. The GA-CIP combination exhibited an additive effect (FICI = 1). Cytotoxicity assessed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on L929 cells demonstrated acceptable IC50 values for each agent and their combination. Antioxidant capacity was measured using α,α-diphenyl-β-picrylhydrazyl (DPPH), total antioxidant level (TAS), and total oxidant level (TOS) assays, with GA showing potential to mitigate CIP-induced oxidative stress. In silico molecular docking studies targeting DNA gyrase (PDB ID: 2XCT) supported a plausible binding synergy between GA and CIP. These findings suggest that GA, when combined with CIP, may enhance antibacterial efficacy and reduce oxidative damage, representing a promising strategy to address antibiotic resistance in S. aureus.