Rescue of streptomycin activity by piperine in .

To evaluate the modulatory effect of piperine (PIP) on streptomycin (SM) activity in (). SM and PIP minimum inhibitory concentration (MIC) and combinatory activity were determined in HRv and in susceptible and resistant clinical isolates. Ethidium bromide accumulation assay and relative quantification of efflux pumps genes ( and ), after SM and SM+PIP combination exposure, were also performed. PIP concentration of 25 μg/ml (1/4× MIC) was able to inhibit efflux pumps activity, to modulate SM activity in , and conducted changes in the relative quantification of efflux pumps genes. SM+PIP combination was able to rescue the SM-susceptible MIC values in SM-resistant .