An agar well diffusion assay (AWDA) was used for
detection of antagonistic activity. BHI agar plates
(1.5% agar), in which wells were formed, were overlaid
with 10 ml of molten BHI agar (0.75% agar) inoculated
with 25 ll of an overnight culture of the indicator microorganism.
Wells, of 5 mm in diameter and of 18 ll in
capacity, were formed by placing the top of 1 ml sterile
pipet tips on the surface layer before pooring the top
agar layer. Once the top agar layer had hardened, the
tops of the pipet tips were carefully removed to leave
wells and 15 ll of an overnight culture of the putative
inhibitor strain were placed in each well. The plates were
then incubated aerobically for 24 h at 30 C and were
subsequently examined for zones of inhibition. Inhibition
was recorded as negative if no zone was observed
around the agar well. Each antagonistic activity was related
to the area (mm2) of the inhibition zone displayed.