ABSTRACT
Biofilms are communities of microorganisms attached to a surface. Aerophytic biofilms build by phototrophic organisms are responsible for the anaesthetic alteration and damage of works of art in dim light. Microorganisms form highly structured and apparently organized communities called biofilms, in both natural and artificial habitats. The main biofilm expansion is due to bacterial growth together with the production and release of materials in a complex sequence mediated by the microorganisms themselves. Biofilms develop in a wide range of environments and are built by many different organisms, therefore extracellular polymeric substances (EPS) vary in their composition and thus in their chemical and physical properties. The extracellular material, also known as EPS, secreted by cells within the biofilm is a key structuring component of microbial biofilms for attachment, nutrient absorption, and protection against desiccation or biocides as a part of a stress response.
