Phytochemical Profiling, Antibacterial Activity, and Molecular Docking of Ocimum Basilicum L. Leaf Extract from Libya: Eugenol and Linalool Interactions with Staphylococcus Aureus Targets

Abstract

This research aimed to analyze the phytochemical constituents of Ocimum basilicum L. leaf methanol extract from Libya, assess its antibacterial activity against important bacterial strains, and conduct molecular interactions of its major compounds with four essential Staphylococcus aureus protein targets. Gas chromatography-mass spectrometry identified 30 compounds representing 99.36% of the extract, with eugenol (23.08%) and linalool (18.79%) as major constituents. The extract showed stronger activity against Gram-positive strains than against Gram-negative strains. Molecular docking using CB-Dock2 software revealed that eugenol displayed superior binding affinities (range: -6.1 to -6.7 kcal mol⁻¹) compared to linalool (-5.7 to -5.9 kcal mol⁻¹) against four S. aureus targets: ftsA (PDB: 3WQU), tyrosyl-tRNA synthetase (PDB: 1JIJ), clumping factor A (PDB: 1N67), and gyrase B (PDB: 3G75). Eugenol formed hydrogen bonds with key residues including GLU209, SER13, ASP177, SER55, and ASP81. Libyan O. basilicum leaf extract is rich in eugenol and linalool, which demonstrate promising antibacterial activity potentially mediated through interactions with essential bacterial proteins. The unique eugenol-rich chemotype distinguishes Libyan basil from previously characterized varieties. This first report on Libyan basil provides a scientific basis for its potential use in developing natural antibacterial agents, with implications for both human and veterinary medicine, particularly against Gram-positive pathogens.