Polystyrene biodegradation by microorganisms isolated from Sphenophorus levis microbiota

Polystyrene is a polymer that, like other plastics, presents versatile physical and chemical properties, enabling the production of a wide variety of items for distinct applications at a low cost. As demand for this material increases, its accumulation is evident, causing social and ecosystem problems. In parallel, many studies have been conducted to investigate this plastic biodegradation by observing natural processes. In this context, it was verified that larvae of some insects can use polystyrene as a carbon source, which is likely related to their gut microbiota. Therefore, this study proposed using Sphenophorus levis larvae, which were observed in our laboratory ingesting expanded polystyrene, as a research model to identify microorganisms and key genes involved in the biodegradation of this material. The insect larvae were fed a diet restricted to this material. Cultivable microorganisms were collected from the insect's gut for the enrichment process in a culture media in which the polystyrene is the only carbon source. The microorganisms were isolated and cultivated in contact with a polystyrene film. The biofilm formation and the material modifications were analised, revealing structural and chemical changes on the polymer surface.