Speakers - AFHWC2025

Abstract

Medicinal and aromatic plants are an important source of bioactive molecules that could be exploited in the treatment of infectious diseases, offering a natural and often less invasive alternative to conventional treatments. The objective of this study was to examine the antibacterial effect of essential oils (EOs), extracted industrially by steam entrainment from Rosmarinus officinalis, Pistacia lentiscus and Thymus vulgaris, whether fresh or dry, on the growth and survival of six pathogenic bacteria known to be important in food hygiene. Sensitivity and minimum inhibitory concentrations (MICs) were assessed using the agar well diffusion method. We also studied the combined effects of EOs by calculating the fractional inhibitory concentration index (FICI).
The results showed that the strains tested showed variable sensitivity, with inhibition zones ranging from 6 to 49 mm, and higher activity against Gram-positive bacteria. The MIC values ranged from 1.56 mg.mL-1 to 6.25 mg. mL-1. They also revealed that the combinations of EOs were synergistic, antagonistic, additive and indifferent, with proportions of 2%, 1%, 3% and 93%, respectively.  Many EOs have shown a high inhibition capacity, even at low concentrations. This suggests that they could serve as natural antibacterial agents to replace chemical additives used in various industries, including the food industry.

Keywords: essential oils, antibacterial activity, degree of sensitivity, minimum inhibitory concentration, combined effects.