Efeitos isolados e sinérgicos do óleo essencial de Syzygium aromaticum e isotiocinato de alilo frente a bactérias patogênicas

Abstract

Thousands of people are infected each year through food-borne illnesses, which have a major impact on public health and the global economy. In an attempt to ensure microbiological safety, synthetic preservatives are widely used in the food industry, however, they are linked to consumer health risks. Natural extracts and their isolated compounds become a viable alternative as they generally do not pose a risk to human and animal health, in addition to being safe for the environment. In this work, we evaluated the antibacterial effect of Syzygium aromaticum essential oil and allyl isothiocyanate against Bacillus cereus, Escherichia coli, Listeria monocytogenes and Salmonella enterica. The antibacterial activity was performed using the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) using the microdilution technique in broth, with modifications. Furthermore, the effects of the combination between the compounds were evaluated using the checkeboard method through the Fractional Inhibitory Concentration (FIC). The essential oil of Syzygium aromaticum presented MIC ranging between 1,000 and 2,000 μg/mL, while the allyl isothiocyanate ranged from 625 to 2,500 μg/mL. In the checkboard test, an additive effect was observed between the combination of compounds against all bacteria evaluated, with MIC between 19.53 to 500 μg/mL. These findings show that the combination essential oil of clove and allyl isothiocyanate makes it possible to obtain antibacterial activity at lower concentrations than when used alone, increasing the viability of use by reducing organoleptic impacts.