Comparison of different media for the enumeration of Aeromonas sp. in freshwaters

I. KERSTERS, N. SMEYERS AND W. VERSTRAETE. 1996. Ampicillin-dextrin agar (ADA), m-Aeromonas agar (mA), starch glutamate ampicillin penicillin C-glucose agar (SGAP-10C), trehalose agar (TRE) and ampicillin bile salts inositol xylose agar (MIX) were evaluated for the isolation of Aeromonas sp. from aquatic environments. Recovery of pure cultures was excellent on all media, except for Aer. sobria on SGAP-10C and MIX agars. Recovery of Aeromonas sp. from freshwaters was comparable on ADA, mA, SGAP-10C and TRE. The most selective media were SGAP-10C and ADA, which yielded an average reduction factor of more than 2.9 log. The ability to differentiate Aeromonas sp. from the background microbiota present in freshwaters was best on ADA. The present findings indicate that ADA is the most adequate medium for the selective isolation of Aeromonas sp. from freshwaters.