Figure 2.

Effect of S. montana (A) ethanolic extract (EtOH) and (B) essential oil on membrane integrity disruption in C. jejuni NCTC 11,168 in sub-inhibitory concentrations of 0.5× (125 and 500 mg/L), 0.25× (62.5 and 250 mg/L), and 0.125× (31.25 and 125 mg/L) of the minimal inhibitory concentration (MIC), presented in relative fluorescent units (RFU) measured for 1 h in 1 min intervals. Fold increase in EtBr accumulation (C) in the treated culture compared to untreated culture is shown for S. montana ethanolic extract and essential oil, and 6 pure compounds, at the subinhibitory concentration of 0.25× MIC. Reserpine at 10 mg/L was used as a positive control. A higher value presents higher accumulation of ethidium bromide and thus a lower activity and inhibition of C. jejuni efflux pumps. *, p < 0.05 (Student’s t-test).