Figure 5

C − S conjugate inhibited bacterial biofilm formation.

The following bacteria were seeded in 96-well plates in the presence of 0.25 mg/mL C − S conjugate (23% streptomycin, ~13 kDa chitosan), equivalent chitosan (C) or streptomycin (S) alone and the respective mixture (C + S) for hours indicated. Biofilms incubated in TSB containing phosphate-buffered saline were used as control. (A and B) L. monocytogenes (6, 12, 24 h); (D) Listeria innocua (24 h); (E) Listeria welshimeri (24 h); (F) Staphyloccocus aureus (24 h). Biofilm mass and viable cells were quantified and L. monocytogenes biofilm architectures after 24 h treatment were further examined by scanning electron microscopy (C). These experiments were performed 3 times with similar results each time. Error bars represent SD.