This experiment was performed by the method of Hayes and Markovic (2002) with some modifications. Propionibacterium
acnes was incubated in brain heart infusion medium (BHI) with 1% glucose for 72 h under anaerobic conditions
and adjusted to yield approximately 1.0×108 CFU/ml. Aliquots of molten BHI with glucose agar were used as an
agar base. A prepared inoculum was added to molten agar, mixed and poured over the surface of the agar base and left to solidity. A sterile paper disc was impregnated with test material and the disc was placed on the agar. Plates were then
incubated at 37 ◦C for 72 h under anaerobic conditions. Staphylococcus epidermidis was incubated in tryptic soy broth (TSB) for 24 h at 37 ◦C and adjusted to yield approximately 1.0×108 CFU/ml. The procedures were the same as mentioned above except the plates were incubated at 37 ◦C
for 24 h under aerobic conditions. All disc diffusion tests were
performed in three separate experiments and the antibacterial
activitywas expressed as the mean of inhibition diameters
(mm).