Determination of in vitro antimicrobial activity of four essential oils condiments and seasoning

Abstract

The in vitro antimicrobial activity was determined for essential oils of cinnamon, clove, ginger, and mint using three different concentrations (10.0, 1.0 and 0.1%) on twenty-one microorganisms (seven species of yeasts, and 14 species of bacteria). The study involved standardized inoculum of microorganisms – previously grown in nutrient broth and sown through the “in replica plating technique” in Petri dishes containing nutrient agar plus tween 20 – with no treatment (control) and with addition of the different concentrations of essential oils. The results obtained after incubation at 30° C for thirty days showed that, within the parameters used in the experiment, the essential oils of cinnamon and mint presented the highest antimicrobial activity in the concentrations of 10.0 and 1.0%, followed by that from clove in the concentration of 10.0%, which also completely inhibited the growth of all the tested microorganisms.