Background: Salvia species contain bioactive secondary metabolites and possess several
pharmacological activities. The objective of this study was to determine the chemical composition and
antimicrobial activity of essential oil from the aerial parts of Salvia pachystachys.
Methods: The essential oil was obtained by means of hydrodistillation and its components were analyzed
using gas chromatography and mass spectrometry (GC/MS). The minimum inhibitory concentration
(MIC) and minimum bactericidal concentration (MBC) of the oil were determined against standard
microbial strains; Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa
and Candida albicans.
Results: Thirty-six compounds were identified in the oil. The major volatile components were camphor
(31.0%), 1,8-cineol (13.5%), camphene (11.7%) and α-pinene (8.0%). Oxygenated monoterpenes predominated
in the S. pachystachys oil, and constituted 50.7% of the total oil composition. The values of
MIC and MBC for the most sensitive strain, Staph. aureus, were 1.25 and 5.0 mg/mL, respectively, and
for the most resistant strain, Pseudomonas aeruginosa and E. coli, were 5.0 mg/mL. Using bioautography
assay, five compounds (camphor, 1,8-cineol, borneol, spathulenol and caryophellene oxide) were
found to be responsible for the observed antimicrobial activity of the oil against S. aureus.
Conclusion: These results indicated that the essential oil of S. pachystachys has moderate antimicrobial