Project Portugal 2030

Summary

The decomposition of plastics in natural environments usually take long periods, demand the interaction of different factors, and lead to the release of toxic compounds (e.g., PAEs). Hence, sustainable and bio-based alternatives are required for degrading plastic wastes even before entering/disposal into the environment. Such alternatives should address challenges associated with the: (i) difficulty in decomposing the stable and chemically-diverse plastic-composing polymers, as well as of their major constituting phthalates; (ii) time, energy and costs required for getting efficient mineralisation of plastics; (iii) management of the generated waste streams during plastics’ degradation; (iv) efficient application at increasing operational scales. The monitoring of plastic wastes and phthalates is also a complementary measure to promote an informed management of plastic pollution in the marine environment. However, current MP and PAE measurement methods have some limitations given the various types of co-occurring plastics with different sizes, the diverse chemical nature of PAEs, and detect realistic levels (often diluted) of in seawater. The 2-DEPLAST intends to address many of these challenges, by proposing a groundbreaking and ever applied (as PI is aware of) strategy based on microbially-synthesised biopolyester beads bioengineered with MPs/PAEs-degrading enzymes. The created biocatalytic beads will be explored into 2 biotechnological dimensions or research lines: (i) as bioremediation agents sustainably produced and used to accelerate MPs/PAEs degradation in scalable reactors; and (ii) as biosensing elements functionalised into optic biosensors to detect selected MPs/PAEs. These major goals will be fulfilled through the following specific objectives: 1. Select and characterise microbes and biosynthesised enzymes able to degrade synthetic MP and PAEs as relevant organopollutants abundantly used in fossil-plastics manufacturing. 2. Bioengineer the microbial synthesis of bioplastic beads coated with MPs- and PAEs-degrading enzymes. 3. Optimise the cost-effective and sustainable biosynthesis of functionalised beads through the valorisation of waste streams derived from MPs/PAEs degradation and other wastes. 4. Set-up of a scalable, sustainable and low energy-demanding system for MP/PAE turnover through the optimisation of combined use of synergistically-acting biocatalytic beads. 5. Develop multiplex biosensors based on optical fibres functionalised with biocatalytic beads to detect different chemical/structural types of MPs and PAEs. Validate the biosensors in seawater samples under realistic concentrations/dilutions. 6. Promote the dissemination, communication and exploitation of the 2-DEPLAST mission, knowledge and results achieved.