Introduction:

Plant extracts have been shown to have antimicrobial properties related to certain chemical compounds such as thymol, carvacrol, limonene, linalool and terpinene. The objective of this study was to determine the concentration of these compounds in the extracts of Larrea tridentata, Origanum vulgare, Artemisa ludoviciana and Ruta graveolens; as well as to evaluate the antimicrobial effect in Escherichia coli, Acinetobacter baumanii, Pseudomona sp and Staphylococcus aureus.

Method:

The extracts were obtained by simple distillation using ethyl alcohol as solvent, the chemical composition was evaluated by gas chromatography. The antimicrobial activity of each of the plant extracts was performed by well diffusion and disk diffusion methods.

Results:

The bacteria showed different degrees of sensitivity to the extracts, S. aureus inhibition of growth with the extract of O. vulgare and R. graveolens, while the bacterium Pseudomona sp. showed inhibition with the extract of A. ludoviciana, L. tridentate and O. vulgare.

Discussion:

The highest concentration of thymol and carvacrol was found in the extracts of O. vulgare and L. tridentata. The compound linalool was found in a higher proportion in O. vulgare and to a lesser extent in A. ludoviciana. Limonene was found in the extracts of O. vulgare and R. graveolens. Of the four plants evaluated, L. tridentata extract was better because it had the highest inhibition compared to the other extracts; and with an effect similar to the oils used as control. The disk diffusion technique allowed better observation of the inhibitory effects of the extracts and oils on each of the bacteria used in comparison to the well diffusion method.