Synthetic and Natural Agents as Bacterial Biofilm Inhibitors

A biofilm is a form of bacterial cluster normally seen in environmental niches. They are immobile communities that colonize and develop on medical implants like sutures, catheters and dental implants, which can be treated only by their removal, leading to unaffordable treatment. The main biofilm consequence is its increased tolerance to negative environmental conditions, which includes resistance to antibiotics and antimicrobial agents. The high resistance of bacterial biofilm towards external stress and antibiotics is due to the extracellular polymeric matrix, which provides a barrier from the external environment. The biofilm development is facilitated by the cell-to-cell communication mechanism of bacteria called quorum sensing, which promotes the bacterial community to mature. There is a huge number of naturally occurring chemical compounds that can act as antibiofilm agents. Different chemical compounds resist bacterial biofilm growth by different mechanisms depending on the chemical structure of the molecule, and the stage of biofilm formation at which we introduce the chemical compound into the biofilm system. The anti-biofilm activity of a natural or synthetic compound mainly depends on certain aspects; some of them will deal with the inhibition of the formation of the polymer matrix, some others may suppress the cell adhesion and its attachment to itself or an external surface, while others deal with the interruption of extracellular polymeric matrix generation and lessening virulence factors production, thereby hindering QS network and biofilm development.

Keywords: Antagonistic, Antibiofilm, Antimicrobial, Autoinducers, Efflux Pump, Extracellular Polymeric Natrix, Multidrug-resistant, N-acyl Homoserine Lactones, Persisters, Photodynamic Therapy, Magnetic Nanoparticles, Violacein, Virulence Factor, Quorum Sensing, Quorum Quenching.