Chemical composition and in vitro biological activities of the essential oils of the rhizomes of Zingiber officinale Roscoe and Curcuma longa L. (Zingiberaceae)

Zingiberofficinale Roscoe and Curcuma longa L. (Zingiberaceae) essential oils were obtained by the hydrodistillation method. The oils offered yields of 0.120% and 0.044% respectively. GC-MS analyzes allowed the identification of 11 constituents in the Curcuma longa essential oil, with major components: ar -turmerone (36.8%), β-tumerone (32.3%) and curlone (19,2%) For the Zingiberofficinale essential oil 19 constituents were identified, being: neral (22.9%), zingiberene (15.5%) and geranial (14.9%) the main components. The result of the toxicity test showed significant activity against Artemiasalina for both oils. The dose values required to eliminate 50% (LC 50 ) of the larvae were 100 µg / mL for Z. officinale and 25 µg / mL for C. longa . The antioxidant activity was performed against DPPH free radical. The most significant activity was exhibited by Z. officinale with an IC 50 value of 215.8 µg / mL. The antibacterial assay with Z. officinale oil showed efficacy against S. aureus and E. coli , with MIC values of ≥ 213.3 μg / mL and 85.3 μg / mL respectively. For C. longa , MIC values ≥ 1024 μg / mL were observed for both bacteria tested. Modulation with aminoglycoside antibiotics showed synergism of C. longa oil combined with amikacin against S. aureus , with a decrease in MIC from 1024 μg / mL to 14.7 μg / mL. Meanwhile, the Zingiberofficinale oil obtained a MIC reduction to 6.7 μg / mL, demonstrating greater efficacy. The results observed here demonstrate the biological potential of the species as cytotoxic and antimicrobial.