Abstract
To improve the sensitivity of microbiological detection of resiudual antibacterial agents in meat and fish, various factors affecting the formation of the inhibition zone were studied. For the media for detecting antibacterial agents, antibiotic medium (AM) 5 was useful for detecting penicillin (PCs), macrolide antibiotics (MLs), and aminoglycosides (AGs) ; AM 8 for tetracyclines (TCs) ; and sensitivity disk agar supplemented with trimethoprim (SD-T) for sulfa drugs (SAs). Optimal conditions were as follows: include the agar concentration, 1.5%. ; medium amount of 8 ml for a 86 mm petri dish; inoculum size, 105 cells per ml of the plate medium. Refrigertion of the plate medium for 30 min prior to imcubation was sufficient. The thin-layer plate/paper disk assay method was more sensitive than in the double-layer plate/cup assay method.
