In this research we investigated releasing of biofilm exopolymeric substance by three strains of Bacillus cereus species. We observed the difference in quality and quantity of produced exopolymers. The proportion between polysaccharides and proteins in EPS depended on the availability of carbon source in the culture environment and the presence of additional adhesion surface. Biological surfaces like poultry feathers stimulated releasing of polysaccharides by tested bacteria, however abiotic surfaces like glass plates induced protein’s releasing. In the proteins of biofilm by SDS polyacrylamide gel electrophoresis revealed the presence of additional fraction of proteins absent in control conditions. Production of exopolymeric matrix by bacteria is regulated by genetic mechanisms but it also highly depends on nutrient level and cultivating time.

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