Designing microbial communities for the environmental- and climate-friendly degradation of end-of-life bioplastics

Bioplastics have a great potential to replace petroleum-based plastics, moreover some of them show a higher biodegradability, forming a closed cycle whereby material used to produce them can be redirected back into soil biomass via microbial degradation. Achieving this vision relies on developing robust biodegradation approaches. Current certified bioplastic degradation protocols have several drawbacks: ecotoxicological impacts of the polymer and the microparticle release are difficult to assess, and microbial species and communities associated with biodegradation and bioplastic-derived carbon recycling into microbial biomass are treated as a black box, leading to high variability in their efficacy. These ambiguities regarding the true biodegradability and sustainability of bioplastics that are generally more expensive than petrol-based plastics prevents their broader acceptance by industry and customers.

The project aims to reduce the environmental persistence of undegraded bioplastics by directing the bioplastic-derived carbon stock for longer-term storage in form of soil microbial biomass. The preliminary and literature data reveal the existence of bacterial species that can enzymatically break-up chemical bonds in specific biopolymers and incorporate monomeric units of the polymer into their biomass.