Exploring the antibiofilm effect of nitrofurantoin and rutin in uropathogenic Klebsiella pneumoniae

Biofilm formation is a critical factor in uropathogenic Klebsiella pneumoniae, enabling colonization in the urinary tract and contributing to biofilm-mediated antibiotic resistance. This study evaluates the anti-biofilm and antimicrobial properties of the nitrofurantoin-rutin (Ntf-Rut) combination against a strong biofilm-forming clinical isolate, K. pneumoniae SLMK002, screened from Klebsiella spp. (n = 15) causing urinary tract infections (UTI). The findings showed Ntf–Rut combination significantly inhibited biofilm mass by 81%, with a 74% reduction in extracellular polymeric substances (EPS). Colony Forming Unit (CFU) enumeration analysis revealed higher cell death in mature biofilm, with CFU reduced from 9 ± 1 × 106 to 2 ± 1 × 106. Further, flow cytometry results prove that the combination induces cell membrane damage. In conclusion, the findings depict that the Ntf-Rut combination effectively reduces and inhibits the biofilm of K. pneumoniae SLMK002.