Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
*Corresponding author Email: h_abdelmonem@yahoo.com
Online published on 5 June, 2014.
The aim of this study was to investigate the ability of ambroxol to block the swarming and swimming motilities and biofilm formation of Proteus mirabilis isolated from diabetic foot ulcers as a new agent for the treatment of diabetic foot infections.
Assays of swarming and swimming motilities on LB agar in the presence and absence of sub-inhibitory concentrations of ambroxol were performed by measuring the distance of swarming and swimming in addition to microscopical examination of vegetative and swarmer cells. Moreover, biofilm formation and removal by ambroxol was investigated in polystyrene microtiter plates.
Ambroxol in sub-inhibitory concentrations significantly blocked swarming and swimming motilities in a dosedependent manner. Ambroxol decreased swarming and swimming at concentrations of 0.6, 0.7, 0.8 and 0.9 mg/ml. At a concentration of 0.9 mg/ml, ambroxol completely inhibited swarming and swimming. Ambroxol also could significantly inhibit biofilm formation and remove pre-formed biofilms in a concentration-dependent manner.
This study suggests that ambroxol could be used for the treatment of Proteus mirabilis diabetic foot infections due to its ability to interfere with swarming and invasion of tissues in addition to inhibition of biofilm formation and removal of established biofilms.
Proteus mirabilis, ambroxol, diabetic foot infection, swarming, swimming, biofilm inhibition
