Detection of AmpC beta-lactamases using sodium salicylate

► Sodium salicylate is an inhibitor that represses AmpC β-lactamases expression. ► Sodium salicylate causes a reduction in β-lactam antibiotic MICs. ► Sodium salicylate can be used in the detection of AmpC β-lactamases in E. coli. ► Sodium salicylate is sensitive in the detection of plasmid-encoded AmpC β-lactamases. ► Sodium salicylate has higher specificity and sensitivity than other known inhibitors.