Avaliação antimicrobiana de três óleos essenciais sobre cepas de bactérias e fungos patogênicos de isolados clínicos

Abstract

The essential oils (EO) of Vetiver (Vetiveria zizanoides), Atlas Cedar (Cedrus atlantica) and Cardamom (Elettaria cardamomum) were tested on different strains of fungi and bacteria, to evaluate their antimicrobial potential, since these oils have data in the literature pointing out beneficial properties, such as: anti-inflammatory, antiseptic, insecticide, astringent and antifungal. The strains used in the experiment were provided by the National Institute for Quality Control in Health of the Oswaldo Cruz Foundation (FIOCRUZ). Four bacterial strains (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus cereus) and four yeasts (Candida glabrata, Candida krusei, Candida albicans and Candida parapsilosis) were selected. In addition, the Minimum Inhibitory Concentration (MIC) of each essential oil was determined. The strain cells were adjusted based on the 0.5 Mc Farland scale and distributed in 96-well microplates. The essential oils were serially diluted in 12 wells of the microplates, using Mueller Hinton broth (for bacteria) and BHI (for yeasts), previously homogenized in 2% Tween 80. The plates were incubated at 35ºC for 24/48 hours and at Presence or absence of growth was checked using resazurin dye. The results demonstrated the inhibitory activity of the essential oils of Vetiver, Cedar do Atlas and Cardamom against the tested bacterial and yeast strains. These results suggest the potential of Vetiver, Atlas Cedar and Cardamom essential oils as disinfectant/antiseptic agents, especially against microorganisms resistant to known antibiotics and of clinical interest. However, additional studies are needed to further confirm and explore these antimicrobial effects.