a b s t r a c t
This study reports for the first time on the chemical composition, toxicity and antibacterial activity of the
of Lantana caatingensis essential oil (LcEO), a medicinal plant from Northeastern Brazil. The essential oils
were analyzed by GC–MS, GC-FID and NMR. The quantitative analysis of the anti-staphylococcal activity
was carried out by determining their percentage inhibition degree. From the chemical constituents of
the essential oil analyzed, we observed a high proportion of sesquiterpene hydrocarbons, being the -
caryophyllene and bicyclogermacrene its main representatives. The toxicity evaluation was performed on
Artemia salina with results considered active (LC50 < 100g/mL). The antimicrobial activity was evaluated
separately and in association of aminoglycoside antibiotics with LcEO by microdilution method. The
results indicated that LcEO can be an alternative source of natural products with antibacterial action, being
capable of inhibiting the bacteria Staphylococcus aureus with MIC values of 64g/mL. The combination of
LcEO with aminoglycoside antibiotics against S. aureus showed significant synergism, with 75% reduction
in the concentration to the MIC value of amikacin.