Ocimum basilicum: Antibacterial activity and association study with antibiotics against bacteria of clinical importance

• Published in: Pharmaceutical biology 2016-05, Vol.54 (5), p.863-867
• Main Authors: Araújo Silva, Viviane, Pereira da Sousa, Janiere, de Luna Freire Pessôa, Hilzeth, Fernanda Ramos de Freitas, Andrea, Douglas Melo Coutinho, Henrique, Beuttenmuller Nogueira Alves, Larissa, Oliveira Lima, Edeltrudes
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - isolation & purification; Anti-Bacterial Agents - pharmacology; Ciprofloxacin; Ciprofloxacin - pharmacology; Humans; imipenem, Staphylococcus aureus; Microbial Sensitivity Tests - methods; Ocimum basilicum; Oils, Volatile - isolation & purification; Oils, Volatile - pharmacology; Plant Leaves; Plant Oils - isolation & purification; Plant Oils - pharmacology; Pseudomonas aeruginosa; Pseudomonas aeruginosa - drug effects; Pseudomonas aeruginosa - physiology; Staphylococcus aureus - drug effects; Staphylococcus aureus - physiology
• ISSN: 1388-0209; 1744-5116
• DOI: 10.3109/13880209.2015.1088551

Context: Ocimum basilicum L. (Lamiaceae), popularly known as basil, is part of a group of medicinal plants widely used in cooking and known for its beneficial health properties, possessing significant antioxidant effects, antinociceptive, and others. Objective: The objective of this study is to determine the pharmacological effects produced on the bacterial strains Staphylococcus aureus and Pseudomonas aeruginosa when standard antibiotics and O. basilicum essential oil are combined. Materials and methods: The extraction of O. basilicum (leaves) components was done by steam distillation. The Minimum inhibitory concentration (MIC) was calculated using microdilution technique, where the oil concentrations varied from 2 to 1024 μg/mL. The combinations of O. basilicum oil with ciprofloxacin or imipenem were analyzed by the checkerboard method where fractional inhibitory concentration (FIC) indices were calculated. Results: Ocimum basilicum essential oil, imipenem, and ciprofloxacin showed respective MIC antibacterial activities of 1024, 4, and 2 μg/mL, against S. aureus. In S. aureus, the oil with imipenem association showed synergistic effect (FIC = 0.0625), while the oil with ciprofloxacin showed antagonism (FIC value = 4.25). In P. aeruginosa, the imipenem/oil association showed additive effect for ATCC strains, and synergism for the clinical strain (FIC values = 0.75 and 0.0625). The association of O. basilicum essential oil with ciprofloxacin showed synergism for clinical strains (FIC value = 0.09). Conclusion: Ocimum basilicum essential oil associated with existing standard antibiotics may increase their antibacterial activity, resulting in a synergistic activity against bacterial strains of clinical importance. The antibacterial activity of O. basilicum essential oil may be associated with linalool.