title: Combined Plate Microbial Assay (CPMA): a 6-plate-method for simultaneous first and second level screening of antibacterial residues in meat.
abstract: This paper proposes an improved high throughput microbial method for the simultaneous performance of first and second level screening for antibacterial residues in meat. It is based on growth inhibition of B. subtilis on agar medium pH 6, 7.2 and 8, of B. cereus on agar medium pH 5.9, of M. luteus on agar medium pH 8 and of E. coli on agar medium pH 7.2 (research or first level screening) and on the use of confirmatory solutions (Pase, Paba, MgSO4) for the identification or second level screening. In kidney control samples, dialysis membranes were interposed between samples and the agar surface to both prevent the action of lysozyme and reduce false positive results. The proposed method detects beta-lactams, sulfonamides, tetracyclines, aminoglycosides, macrolides and quinolones at MRL concentrations and reliably indicates the inhibitor family. Results are obtained in 18-24 h.
authors.affiliation: Istituto Superiore di Sanità, National Centre for Food Quality and Risk Assessment, Roma, Italy.
authors.forename: A M
authors.initials: AM
authors.lastname: Ferrini
authors.forename: V
authors.initials: V
authors.lastname: Mannoni
authors.forename: P
authors.initials: P
authors.lastname: Aureli
mesh_terms: D000362:Agar; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D001409:Bacillus cereus / Q000187:drug effects; D001412:Bacillus subtilis / Q000187:drug effects; D003470:Culture Media; D004350:Drug Residues / Q000032:analysis*; D004926:Escherichia coli / Q000187:drug effects; D005506:Food Contamination / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D008460:Meat / Q000032:analysis*; D008826:Microbial Sensitivity Tests / Q000379:methods; D016982:Micrococcus luteus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D000362:Agar