TABLE 3

Summary of activity parameters for AMB and CAS in combination with TrcA, TrcB, and TrcC against 24-h-old C. albicans biofilmsa

Tyrocidine concn (μM)Plus TrcAPlus TrcBPlus TrcC
AMBCASAMBCASAMBCAS
BEC50 (μM)bFICIcBEC50 (μM)FICIBEC50 (μM)FICIBEC50 (μM)FICIBEC50 (μM)FICIBEC50 (μM)FICI
6.20.110.250.040.110.060.140.030.150.210.340.150.12
3.00.120.230.040.100.140.270.040.120.170.280.060.15
1.80.220.410.060.180.220.420.060.190.220.350.130.35
00.561.000.351.000.561.000.351.000.561.000.351.00
  • a Each value represents the mean of ≥3 biological repeats, with 2 to 5 technical repeats per assay ± standard error of the mean (SEM).

  • b The BEC50 value, derived from a full dose-response curve, represents the concentration AMB or CAS at which 50% eradication was achieved in the presence of a constant tyrocidine concentration. The AMB and CAS dose-response concentration ranges were 0.04 to 5.0 μM and 0.02 to 2.5 μM, respectively.

  • c The fractional inhibitory concentration index (FICI) was calculated using the BEC50 obtained for combinatorial treatment and the BEC50 values for the individual compounds (Table 2).