The initial phases of attachment are very crucial in the biofilm development process. The control of surface attachment can inhibit the whole process of biofilm development. Biofilm formation can also be inhibited by the inhibition of adhesin and EPS molecules. When the bacteria have short-range interaction with the surface, the hydrophobic interactions, dipole, ionic, and hydrogen bonds begin to dominate over some other interactions, and then bacteria start to attach through the cellular or molecular phase
[24] (
Figure 1). Surfactants are the popular choice of antimicrobial agents for inhibiting bacterial adhesion to the surfaces as they decrease the interfacial tension between two substances. Surfactants are amphiphilic as they comprise of hydrophilic and hydrophobic moiety and at the same time, they can be categorized as non-ionic, anionic, cationic, and amphoteric surfactants
[22]. Triton X-100 and Tween 80 (Polysorbate 80) are the two popular non-ionic, synthetically derived, and regularly used surfactants in laboratories. Tween 80 decreased
S. aureus medical device associated biofilm development at concentrations safe in humans
[25]. Triton X-100 could stimulate autolysis by enhancing bacterial vulnerability to antibiotics and altering the architecture and physiological features of biofilms by reducing the protein and carbohydrate constitution in the EPS
[26][27]. Biosurfactants are the surface-active compounds created by microorganisms that comprise structurally diverse biomolecules
[28]. Cationic surfactants such as quaternary ammonium compounds (QACs) are used as disinfectants within the food industry and used in several medical conditions. QACs bind to negatively charged areas in microbes that cause stress to the cell wall, lysis, and cell death. QACs could also cause protein denaturation that affects cell wall permeability and reduces the uptake of nutrients. Non-ionic-based surfactants incorporating poloxamer 188, are regarded as non-cytotoxic and therefore represent a useful combination in wound care. Numerous studies using antimicrobials together with poloxamers showed enhanced antimicrobial efficacy
[29]. Similar to regular surfactants, numerous biosurfactants have antimicrobial activities while some even seem to prevent surface colonization by pathogens
[22]. One of them is rhamnolipid, which is the chief glycolipid formed by several bacterial species, chiefly by
P. aeruginosa [30], and stimulates biofilm dispersal in
P. aeruginosa, S. aureus, Salmonella enteritidis, and
Listeria monocytogenes [31]. Furthermore, rhamnolipids from
P. aeruginosa W10 were also known to disperse biofilms of various industrial bacterial strains on the pipelines
[32]. Since biosurfactants are usually associated together with isomers and cogeners and rarely in pure form, the purification process could be exhaustive and expensive
[33]. At the same time, they could be very cytotoxic and hemolytic due to their activity with cellular membrane
[34]. Therefore, their use for controlling biofilms could be limited to coating medical devices and anti-adhesive agents.