Figure 5.

Phototoxicity of the Skm ethanol extract in established bacterial biofilms. S. aureus cells were allowed to form biofilms covering the entire well surface for 48 h in plastic microplates before treatment with bleach or Skm ethanol extract at doses ranging from 63 to 500 µg·mL⁻¹ at dark (grey bars) or after light illumination (total fluence of 25 J·cm⁻², white bars). The biofilm remaining after treatment was colored with Coomassie blue and quantified by spectrophotometry at 595 nm. All experiments were performed in triplicate independent assays.