First lead structure for nitrofurantoin resistance inhibition activity against Enterobacteria

Abstract

We have previously shown that the ethanolic diluted essential oils of the aerial parts of Mentha longifolia could have nitrofurantoin resistance breaker activity against nitrofurantoin resistances Entherobacteriaceae. Bioassay-guided fractions of silica gel thin layer chromatography elute using the nitrofurantoin resistance test strains resulted one compound in active fraction containing a monoterpene piperitone. Piperitone at the concentration of 1 mg/mL decreased MICs of all resistance strains to less than 32 μg/mL. In the presence of piperitone the MICs of nitrofurantoin becomes about 8 times smaller than that of in its absence. Also it is found that in the presence of piperitone the emergence of nitrofurantoin-resistant variants among wild type strains is completely suppressed. Taken together, these results indicate that piperitone could have potential therapeutic effect on nitrofurantoin-resistance chemotherapy.

Keywords

• nitrofurantoin
• piperitone
• antibiotic resistance
• potentiation activity