Advancing Industrial Biotechnology: Low-Cost and Performant Microbial Polyesters for Sustainable Packaging

Plastic pollution poses a pressing global issue. With annual production exceeding 380 million tonnes and a growth rate of 4% per year (Rosenboom\_et\_al.,\_2022), the problem demands immediate attention. Packaging stands out as the primary contributor, accounting for 42% of primary plastics usage in 2015 (ourworldindata.org).

Furthermore, the plastic industry's yearly greenhouse gas emissions surpass 400 million tons, surpassing the entire carbon footprint of the UK (UN Environmental Report, 2021). Various recycling solutions have emerged in an attempt to reduce the volume of virgin plastics we use; however, most plastic waste is not prevented or recycled due to obstacles such as material soiling, e.g., plastic contaminated with food residues, non-separable mixed materials, insufficient collection systems and infrastructure, and weak industrial demand for recycled materials.

Of the global plastic produced between 1950 to 2015, 55% went straight to landfills or was discarded, 8% was incinerated, and only 9% was recycled (ourworldindata.org). Meanwhile, increased demand fuelled by global population growth and vital economic development by far outstrips any reductions achieved.

Therefore, innovative compostable materials that offer the same functional properties, convenience, and versatility as plastics yet disappear from the environment at the end of their useful life are essential for disrupting the plastics industry in packaging and beyond. Yet, these innovative materials still need to be in wide commercial use - something that Shellworks, an award-winning startup founded in 2019 by two Imperial College graduates, is set on changing.

New innovations in compostable materials led by Shellworks are offering mono-material solutions with the same compost outcomes at the end of life, eliminating the need for mixed-material solutions while alleviating the burden on current waste infrastructure.

This project aims to create sustainable alternatives for the food packaging industry by harnessing microbial biosynthesis to produce revolutionary and innovative biopolymers using 2nd and 3rd generation feedstocks. This will be a new engineering biology product that will enable Shellworks to radically extend the range of products they offer, and conquer a much larger share of the packaging market while delivering a material solution that improves the feedstock's resilience and sustainability for biopolymers production.

The new material would unlock entirely new properties that the current home-compostable and biobased materials can't offer. This project's outputs will play a key role in supporting the UK's ambition to become a world leader in sustainable packaging and helping with the targets of the UK Plastic Pact.