Antibacterial Activity of Ocimum basilicum Essential Oil and Linalool on Bacterial Isolates of Clinical Importance

Ocimum basilicum, popularly known as Basil, is a Lamiaceae family species widely known to treat different diseases. This species has as its main compound the monoterpene linalool. This study aimed to determine the antibacterial activity of O.basilicum essential oil and linalool against S. aureus and P. aeruginosa strains, as well as times to bacterial death facing each substance. The extraction of the O. basilicum leaves components was made by steam distillation. The Minimum Inhibitory Concentration (MIC) was calculated using microdilution technique and assessment of bacterial kinetics was performed with time-to-kill methodology. The results showed that O. basilicum essential oil and linalool display antibacterial activity against both S. aureus and P. aeruginosa, with certain strains of P. aeruginosa being resistant to the oil. Bacterial kinetics testing showed bacteriostatic activity against the strains in almost all concentrations, while only the MIC x 4 concentration of either essential oil or linalool against S. aureus displayed bactericidal activity. We conclude that the O. basilicum essential oil has antibacterial activity characterized as bacteriostatic or bactericidal against clinical isolates, and this activity is likely associated with linalool, its major compound.