Biofilm control agents

This type of program relies as much on the detergent and surfactant properties of the biofilm control agent as it does on its biocidal properties. With the use of BCAs, rather than sole reliance of heavy-duty biocides, the sessile microorganisms are swept into the main body of the cooling system. More traditional biocides may still be required periodically. 

Antifoulants (metal surface cleaners) to reduce the risk of pitting corrosion and other forms of concentration cell corrosion, initiated at the metal surface by shielding effects from inorganic deposits or biofilms. These could also be called deposit control agents. 

Chloramines may be combined with other agents for special effects (e.g., with chlorine dioxide for further biofilm control and DBP reduction, and with ozone to prevent nitrification). 

Stewart, P., McFeters, G. and Huang, C., 2000. Biofilm control by antimicrobial agents. In J. Bryers (ed.). Biofilms II Process Analysis and Applications, Farmington, Connecticut, University of Connecticut Health Center, pp.373-405. 

Knowledge of the composition of shme deposits and the formation mechanisms of biofilms has led to more selective slime control agents, in combination with the use of chemicals that are capable of either penetrating the biofihns or dispersing the deposits. So less toxic substances can be used in the system and keeping machine surfaces is easier. 

Resistance to antimicrobial agents is of concern as it is well known that bacterial resistance to antibiotics can develop. Many bacteria already derive some nonspecific resistance to biocides through morphological features such as thek cell wall. Bacterial populations present as part of a biofilm have achieved additional resistance owkig to the more complex and thicker nature of the biofilm. A system contaminated with a biofilm population can requke several orders of magnitude more chlorine to achieve control than unassociated bacteria of the same species. A second type of resistance is attributed to chemical deactivation of the biocide. This deactivation resistance to the strong oxidising biocides probably will not occur (27). 

The biosphere includes ecological niches where microbes peacefully co-exist with their eukaryotic host in the human this includes the concept of the micro-biome [14], which is defined as the totality of microbial organisms that co-habit with human beings. On the other hand, microbial colonization of human mucosal surfaces or prosthetic devices, often results in the development of biofilms, with significant deleterious effects on human health [15]. These are some of the challenges in infectious diseases that reflect the need to maximally utilize genomic sequence information and related sciences to better control microbial disease in human populations, and to develop anti-microbial agents with a better therapeutic index. 

Recently [ 152], a novel strategy has been described for controlling biofilms through generation of a biocide (hydrogen peroxide) at the biofilm-surface interface rather than simply applied extrinsically. In this procedure, the colonized surface incorporated a catalyst that generated active biocide from a treatment agent. 

Rice, S. A., Mcdougald, D., Kumar, N., Kjelleberg, S. The use of quorum-sensing blockers as therapeutic agents for the control of biofilm-associated infections. Curr. Opin. Investig. Drugs 2005, 6, 178-184. 

Nichols, W.W., 1994, Biofilm permeability to antibacterial agents, in Wimpenny, J., Nichols, W., Stickler, D. and Lappin-Scott, H. eds. Bacterial Biofilms and their Control in Medicine and Industry. Bioline, School of Pure and Applied Biology, University of Wales College of Cardiff, 141-149. 

We also utilized scanning electron microscopy to evaluate the morphology of E. coli and S. aureus biofilms and the effect the coated surfaces have on biofilm formation. As presented in Figure 4.20, dense bacterial colonization can be seen in the untreated glass controls while no biofilm formation is observed ion coated surfaces. These results suggest that Mgp2 nanoparticles are extremely effective antibiofilm agents. 

Ma H, Darmawan ET, Zhang M, Zhang L, Bryers JD. Development of a poly(ether urethane) system for the controlled release of two novel anti-biofilm agents based on gallium or zinc and its efficacy to prevent bacterial biofilm formation. J Control Release 2013 172(3) 1035 4. 

I., Vinogradov, A.M., Stewart, P.S., Ratner, B.D. et al. (2005) Ultrasonically controlled release of ciprofloxacin from self-assembled coatings on poly(2-hydroxyethyl methacrylate) hydrogels for Pseudomonas aeruginosa biofilm prevention. Aniirtdcrdh. Agents Chemother., 49, 4272—4279. 

Microbial cells living in biofilms are much more difficult to eradicate or control than suspended cells. Yet the susceptibility of biofiim cells to antibiotics and industrial antimicrobial agents is rarely assessed. In part, this is due to convention and, in part, because standard testing protocols against suspended cultures... 

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