Antimycobacterial Precatorin A Flavonoid Displays Antibiofilm Activity against BCG.

The aim of this study was to evaluate the potential antibiofilm activity of () compounds over BCG ( BCG) as a model for (). We evaluated the antibiofilm activity as the ability to both inhibit biofilm formation and disrupt preformed biofilms (bactericidal) of compounds, which have been previously described as being antimycobacterials against . BCG developed air-liquid interface biofilms with surface attachment ability and drug tolerance. Of the extracts and compounds that were tested, precatorin A (PreA) displayed the best biofilm inhibitory activity, as evaluated by biofilm biomass quantification, viable cell count, and confocal and atomic force microscopy procedures. Furthermore, its combination with isoniazid at subinhibitory concentrations inhibited BCG biofilm formation. Nonetheless, neither PreA nor the extract showed bactericidal effects. PreA is the compound responsible for biofilm inhibitory activity against BCG.