3.6 Synergy Studies
Combinations of ethanol extracts displaying strong antimicrobial properties were assessed for
synergistic/antagonistic activities. The FIC indices of ethanol extracts displaying antimicrobial properties are
shown in Table 3. With reference to FIC scale, none of the combinations displayed a synergistic effect (FICindex<
0.5) against any of the bacteria tested, however, some additive effects (0.5 ≤ FICindex ≤ 1) were noted in
combinations containing oregano. Oregano combined with rosemary or sage had an additive effect against L.
innocua and S. aureus. However, additive effects could not be observed against E. coli or P. fluorescens.
Antagonistic effects were not observed for any of the combinations.