Rescue of streptomycin activity by piperine in <i>Mycobacterium tuberculosis</i>

Aim: To evaluate the modulatory effect of piperine (PIP) on streptomycin (SM) activity in Mycobacterium tuberculosis ( Mtb ). Materials & methods: SM and PIP minimum inhibitory concentration (MIC) and combinatory activity were determined in Mtb H 37 Rv and in susceptible and resistant clinical isolates. Ethidium bromide accumulation assay and relative quantification of efflux pumps genes ( rv1258c, rv1218c and rv2942 ), after SM and SM+PIP combination exposure, were also performed. Results: PIP concentration of 25 μg/ml (1/4× MIC) was able to inhibit efflux pumps activity, to modulate SM activity in Mtb , and conducted changes in the relative quantification of efflux pumps genes. Conclusion: SM+PIP combination was able to rescue the SM-susceptible MIC values in SM-resistant Mtb .