Polysacharide-based Materials as Support for Ideonella Sakaiensis with Applications in Wastewater Remediation

The accumulation of microplastics (MPs) in surface water is a growing environmental challenge due to their persistence and the health risks they pose to both aquatic organisms and humans. The biological treatment in wastewater plants employs activated sludge microorganisms to decompose organic compounds in the effluent and plays a key role in reducing the spread of microplastics into the environment. This paper presents the preparation and characterization of different polysaccharide- based scaffolds acting as a carrier for bacteria specialized in MP degradation. The bacterial-loaded sodium alginate scaffold was prepared by the ionotropic gelation method, using calcium chloride as a cross-linker. The performance of bacterial immobilization is determined by the material properties, such as porosity and structural resistance, which are strongly influenced by the concentration of polysaccharides, crosslinking method, and the composition of the polysaccharide mixture. Bacterial cell viability was assessed using fluorescence microscopy, which indicated that alginate crosslinked in CaCl 2 solution is the most versatile material for this application.