MIC and FIC indices of cefotaxime in combination with EGCG against ESBL-EC.

A, Cefotaxime alone; B, plus EGCG (50 mg/L); C, plus EGCG (100 mg/L); D, plus EGCG (250 mg/L). The MIC of EGCG alone was 1500 mg/L.aFractional inhibitory concentration (FIC) was calculated as MIC of antibiotics alone or EGCG in com-bination divided by MIC of antibiotics or EGCG alone, and the FIC Index was obtained by adding theFICs.bFIC indices were interpreted as below: ≤0.5, synergy; >0.5 to 1, addition; and >1, indifference.