AVALIAÇÃO DA COMPOSIÇÃO QUÍMICA E ATIVIDADE ANTIBACTERIANA DOS ÓLEOS ESSENCIAIS DE Aloysia gratissima (Gillies & Hook) Tronc. (ALFAZEMA), Ocimum gratissimum L. (ALFAVACA-CRAVO) E Curcuma longa L. (AÇAFRÃO)

Abstract

The discovery of antimicrobial natural substances demonstrated for plants has been the target of several scientific studies. The essential oils of the Aloysia gratissima (Gillies & Hook) Tronc., Ocimum gratissimum L. and Curcuma longa L. was extracted by steam-distillation using a Clevenger modified apparatus and were analyzed to the chemical composition and antibacterial activity. The analysis of the chemical composition was carried out by GC/MS and antibacterial activity was evaluated by agar diffusion with the microorganisms Staphylococcus aureus ATCC 6538, Salmonella choleraeseus ATCC 10708 and Escherichia coli O:158. The antibacterial activity of the essential oil of Ocimum gratissimum L., was evaluated by bioautography. Among the studied samples, Ocimum gratissimum L. was the only active against all strains. The growth of Staphylococcus aureus ATCC 6538 was inhibited by the three studied essential oil. For the bioautography experiments it was verified that eugenol was the main bioactive component in the essential oil of Ocimum gratissimum L.