Bacterial activity in nature is predominantly associated with surface-bound microbial communities that form complex and heterogeneous assemblages consisting of single or multiplespecies biofilms. These aggregates are involved in several human activities, ranging from the detrimental effects of unwanted biofilms in human health and industry to beneficial uses in environmental treatment processes. In the present day, sophisticated 2D/3D biofilm models include first-principle based descriptions of several processes involved in biofilm formation: attachment of cells to a surface, growth, diffusion and reaction of solutes throughout the biofilm matrix, production of extracellular polymeric substances (EPS), biomass detachment resultant from shear stress, etc. The latest generation of multidimensional models allows the description of multispecies biofilms, at the same time including any number of solute species (e.g. carbon source, dissolved oxygen, soluble metabolites, etc.) reacting. In this talk, the newest advances on biofilm modelling carried out at Technical University of Delft will be presented, with emphasis on the individual based modelling of multispecies biofilms. Case studies will be shown, illustrating how modelling provides surprising insight into many aspects of biofilms, including:
-The relationship between biofilm structure and its activity
-The occurrence of sloughing, i.e. losses of large amount of biomass from a biofilm
-Reproducibility of the biofilm structure
-Competition and cooperation between microbial species in multispecies biofilms
-The role of the EPS matrix and of internal storage compounds