GC–MS Profiling and Molecular Docking of Clove Leaf Oil Constituents Against Xanthine Oxidase

Background: Hyperuricemia and gout are metabolic disorders whose prevalence continues to increase and are closely associated with the activity of the enzyme xanthine oxidase (XO), which catalyzes the formation of uric acid. The use of synthetic XO inhibitors such as allopurinol and febuxostat is still limited by the risk of adverse effects during long-term therapy; therefore, the exploration of natural compounds is relevant. Objective: This study aimed to identify the dominant volatile constituents of clove leaf essential oil (Syzygium aromaticum) using gas chromatography–mass spectrometry (GC–MS) and to assess the predicted binding of eugenol and β-caryophyllene to xanthine oxidase through molecular docking. Methods: Clove leaf essential oil was obtained by steam–water distillation and profiled by GC–MS using an SH-Rxi-5Sil MS column. Eugenol and β-caryophyllene, the two dominant constituents, were docked to the active site of xanthine oxidase using PyRx 0.8 and visualized with PyMOL 2.0.4; allopurinol and febuxostat served as reference ligands. Results: GC–MS profiling identified eugenol (71.97%; retention time, 10.036 min) and β-caryophyllene (23.68%; retention time, 10.852 min) as the dominant constituents. Molecular docking predicted binding energies of −7.0 kcal/mol for eugenol and −7.2 kcal/mol for β-caryophyllene, compared with −6.3 kcal/mol for allopurinol and −9.1 kcal/mol for febuxostat. These values indicate predicted ligand–protein affinity and do not constitute direct evidence of enzyme inhibition. Conclusion: Eugenol and β-caryophyllene from clove leaf essential oil showed potentially relevant predicted interactions with xanthine oxidase in silico. Experimental enzyme-inhibition assays are required before biological inhibitory activity or therapeutic potential can be established.