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In this study, we investigated the effect of different multivalent cations on granule formation. Previous experiments showed that formation of matrix EPS and their structure depend of the presence of divalent cations. This study indicates that trivalent cations are also playing an important role. However, the more compact granules were formed in the presence of all cations. The authors tried also to determine changes in proteomic profile of slime and tightly bound EPS. These results showed that matrix EPS is composed of a variety of large and complex proteins, but there are also small proteins, like for example, lectins. These small proteins have a role in the interaction between cells and exopolysaccharides and in granules formation.

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This study investigated the quantity and distribution of extracellular polymeric substances (EPS) in aerobic granules. Results showed that EPS play an important role in the formation and stabilisation of granules. The content of EPS significantly increases during the first weeks of biogranulation. An analysis of EPS in the granules revealed that the protein level was 5 times higher than in polysaccharides. The increase of protein content correlated with the growth of cell hydrophobicity (r2 = 0.95). EPS and hydrophobicity are important factors in cell adhesion and formation of granules. The aim of this work was also to determine the distribution of EPS in the granule structure. In situ EPS staining showed that EPS are located mostly in the center of granules and in the subsurface layer. The major components of the EPE matrix are proteins, nucleic acids and β-polysaccharides. These observations confirm the chemical extraction data and indicate that granule formation and stability are dependent on protein content.

This preliminary studies concerns preparation of biopolymer carriers for immobilization of laccase from Trametes versicolor, based on sodium alginate, chitosan and on a combined alginate-chitosan biopolymers as well as the evaluation of their potential use in the decolourization process. The study is related to the assessment the using of various carriers in the immobilization methods of laccase. The dropping method using sodium alginate (2%) proved to be the most effective technique of enzyme immobilization. The study showed an improvement in the stability of immobilized laccases under the conditions of variable pH, relative to a free laccase. A loss in the stability of enzymes in alginate beads occurs at high temperatures, together with enzyme leaching and degradation. Enzyme leaching from the beads inhibits their preliminary low-temperature drying. Immobilization and drying of obtained capsules constitutes a promising method for improving enzyme stability. The results obtained as part of this study offer a valuable contribution to the future research on the possibility of using the prepared alginate beads to remove colour contamination from wastewater.