Research Article

Synergistic Effect and Antiquorum Sensing Activity of Nymphaea tetragona (Water Lily) Extract

Table 4

Fractional inhibitory concentration (FIC) and FIC index (FICI) of combination between streptomycin and EFNTE.

StreptomycinEFNTEFICIInterpretation
Conc ( g/mL)FIC of drug AConc ( g/mL)FIC of drug B(FIC of A + FIC of B)

32MIC of A0MIC of AMIC of AMIC of A
32160.00771.008IND
160.5120.01540.515ADI
160.5240.03070.531ADI
160.5490.0630.563ADI
160.5980.1250.625ADI
160.51950.250.75ADI
160.53910.51IND
80.2578111.25IND
40.12578111.125IND
20.062578111.063IND
0MIC of B781MIC of BMIC of BMIC of B

EFNTE: ethyl acetate fraction of N. tetragona 50% methanol extract; Conc: concentration; drug A: streptomycin; drug B: EFNTE; ADI: additive effect; IND: indifferent effect; MIC: minimum inhibitory concentration. The FICI was interpreted as follows: synergistic effect (0 < FICI ≤ 0.5), additive effect (0.5 < FICI ≤ 1), and indifferent effect (1 < FICI ≤ 4).