Enhancement of antimicrobial activity of pump inhibitors associating drugs

with the continuous emergence of pathogenic resistance to conventional drugs through efflux pumps, increasing efforts are directed toward discovering efflux inhibitory molecules. in this study three P-glycoprotein (P13CP, P22CP, P34CP) efflux-inhibitors (EIs), belonging to the series of phenoxymethylquinoxalines capable to restore/potentiate the antiproliferative activity of doxorubicin and vincristine against human tumor cell lines and different antibiotics against clinical isolates, were investigated on 10 clinical strains of Candida and 12 clinical and ATCC strains of Gram positive and Gram-negative bacteria. MFC values of FLC were reduced in all Candida strains by the P22CP and P34CP inhibitors, and in 5/10 fungal strains by the P13CP inhibitor. novel antibiotics with new modes of action are urgently required to suppress the rise of MDR bacteria. An alternative approach would be to identify molecules that can interfere with the process of efflux.