Biofilms control

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. 

The use and inspection of mesh screen coupons or washers placed in simple biofilm monitors can also help in biofilm control evaluation. Essentially, if an inspection gives some assurance that the cooling system is clean, it most probably is clean ... 

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). 

Blenkinsopp et al [1992] have shown that the efficacy of some biocides against Pseudomonas aeruginosa biofilms grown on stainless steel studs, is increased by the application of a low strength electric field. Biocide concentrations lower than those necessary to kill planktonic cells were bactericidal within 24 h when applied within the electric field. It is possible that this discovery could have implications for industrial biofilm control in the future. 

Pujo, M.D., 1993, Effects of hydrodynamic conditions and biocides on biofilm control. PhD Thesis, University of Birmingham. 

V-halamine as an Antimicrobial and Biofilm-controlling Additive for Polymers... 

Salunke, G.R., Ghosh, S., Santosh Kumar, R.J., Khade, S., Vashisth, P., Kale, T., et al., 2014. Rapid efficien synthesis and characterization of silver, gold and bimetallic nanoparticles from the medicinal plant Plumbago zeylanica and their application in biofilm control. Int. J. Nanomedicine 9, 2635—2653. 

Biofilm Control. Biofilms, often referred to as slime, occur on the surface of aqueous environments and are caused by a complex accumulation of microorganisms. Biofilms are usually considered undesirable, as they are frequently associated with odors, infections, fouling, and corrosion, but they can be beneficial under some circumstances such as the treatment of wastewater. 

Cao Z, Sun Y. Chitosan-based rechargeable long-term antimicrobial and biofilm-controlling systems. J Biomed Mater Res A 2009 89 960-7. 

It is now widely recognized that sessile microorganisms cause the most damage in industrial water systems, and the development of biocides is directed towards biofilm. In order to measure the effectiveness of a biofilm control program, it is essential to accurately monitor the development of biofilms in a system and record their response to control measures. 

Effect of combination of non-oxidizing biocides. Experimental study shows that the combination of nonoxidizing biocides was more efficacious in biofilm control than biocides when used alone (Figure 9). Simultaneous use of isothiazolones (4 ppm) and quaternary ammonium compound (12 ppm) demonstrated better biofilm control than either isothiazolones or quat alone. This biocidal combination controlled biofilm (based on HTR data) for about 27, 30, and 32 hours after three consecutive treatments. The biofilm DO response was much more significant than any separately tested biocide and was similar to the test when isothiazolone was used together with oxidizing biocide. These laboratory results confirmed practical (field) evidence that combinations of biocides affect biofibns more effectively than biocides used alone. 

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. 

Antimicrobial products have been the main weapons used to control unwanted biofilms. Although this strategy is widespread in biofilm control, there are no standardized antimicrobials with reliable efficacy. Strategies to remove unwanted biofilms must take into account the system characteristics, such as the biofihn colonizer species and the EPS composition (SimOes et al. 2009b). It is expected that an effective and wide spectrum biofihn control strategy will overcome the resistance and cross-resistance problems (Gilbert and McBain 2003). 

Torres, C. E., Negro, C., Fuente, E., and Blanco, A. (2012). Enzymatic approaches in paper industry for pulp refining and biofilm control, Appi. Microbiol Biotechnol, 96,327-344. 

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