2.5.1 Disk diffusion method
Briefly, a suspension of the tested microorganism (0.1 ml of 108cellmL −1) was spread on the solid media plates. Filter paper discs (6mm in diameter)were impregnated with 3 different concentrations (10, 20 and 30 μl per disc) of the oil and placed on the inoculated plates (MHA/SDA). The plates were incubated at 37 °C for 24 h for bacteria and at 30 °Cfor 48 h for yeasts. The zone of inhibition was measured with a caliper. Tests were performed in triplicate, and mean value was calculated. Antibiotic discs of Streptomycin (25 μg/disc) and Amphotericin B (20 μg/disc), purchased from Antibiotical company of Saidal (Medea, Algeria) were also used as positive controls for bacteria and yeasts respectively.