Biofilm Control: Conventional and Alternative Approaches

Abstract

“Biofouling” is referred to as the unwanted deposition and growth of biofilms. This phenomenon can occur in an extremely wide range of opportuni- ties ranging from colonization of medical devices, during production of ultrapure drinking and process water, and fouling of ship hulls, pipelines and reservoirs. Although biofouling occurs in such different areas, it has a common cause, which is the biofilm. Biofilms are the most successful form of life on earth and tolerate high concentrations of biocidal substances. Conventional anti-fouling approaches usually rely on the efficacy of biocides, aiming for inhibition of biofilm growth. It is important to keep in mind that killing of biofilm organisms usually does not solve biofouling problems as mostly the biomass is the problem and must be removed. Therefore, cleaning is at least equally important. However, for a sustainable anti- fouling strategy, an advanced approach is suggested, which includes the analysis of the fouling situation, a selection of suitable components of the “anti-fouling menu” and an effective and representative monitoring of biofilm development. One important part of this menu is nutrient limitation, which could be implemented on a much broader scale than is practiced today. Other items on the menu include methods to monitor unwanted biofilm development and assessment of the efficacy of anti-fouling measures. Also, natural anti-fouling strategies are worth exploring and learning from – and nature never relies on only one defence line but on inte- grated approaches. 1