Table 8.

Biofilms and microbial response to antimicrobial agents

Mechanism of resistance associated with biofilmsComment
Exclusion or reduced access of antiseptic or disinfectant to underlying cell  Depends on (i) nature of antiseptic/disinfectant, (ii) binding capacity of glycocalyx toward antiseptic or disinfectant, and (iii) rate of growth of microcolony relative to diffusion rate of chemical inhibitor
Modulation of microenvironmentAssociated with (i) nutrient limitation and (ii) growth rate
Increased production of degradative enzymes by attached cellsMechanism unclear at present
Plasmid transfer between cells in biofilm?Associated with enhanced tolerance to antiseptics and disinfectants?