There are various methods of utilising used plastic in a meaningful way. Another approach is the use of microbes, fungi and enzymes: they not only break down plastic, but also transform it into useful products - including medicines.
Plastic is one of the most important materials of our time - and thanks to its recyclability, it is a central component of the circular economy. A new approach is now opening up: the Biorecycling known from the decomposition of organic waste can also be applied to plastic. It could complement conventional recycling methods and contribute to the targeted degradation of plastic waste released into the environment.
Turbo enzymes, power fungi and super bacteria that break down plastics have already been discovered. One example is „Ideonella sakaiensis“, a bacterium that breaks down PET into its basic building blocks with the help of the enzymes PETase and MHETase. Variants can be used through the targeted selection and optimisation of suitable enzymes, that significantly accelerate plastic degradation.
Fungi such as „Parengyodontium album“ or bacteria called „Pseudomonas stutzeri“ also show impressive degradation performance - even with types of plastic that were previously difficult to recycle. The findings make this clear: Biorecycling enables the efficient utilisation of plastic waste and could become an important source of energy. complementary strategy in dealing with plastics become.
From plastic to medicine
One particularly remarkable approach comes from researchers at the University of Edinburgh. They developed genetically modified E. coli bacteria, the PET in paracetamol, an everyday painkiller and antipyretic. The entire process takes place at room temperature and generates almost no CO₂ emissions - an environmentally friendly alternative to conventional paracetamol production.
Such examples show that plastic is not only degradable, but can also be can also be transformed into valuable raw materials - clean, sustainable and innovative. Even new microbial communities can develop through plastic.
When plastic becomes a bio-platform
So-called „plastispheres“ - tiny microbial habitats created by humans - form on the surfaces of plastic particles. Bacteria, fungi and even small crustaceans settle here. Microbes form complex structures and develop metabolic processes to specifically break down plastic. At the same time, the particles create new habitats for insects and small animals in previously uninhabitable areas of the oceans.
Plastispheres provide insights into utilisation processes and their potential for industrial recycling. Not only in the sea. For example, the leading Swiss research institute for terrestrial environmental systems WSL is searching for bacteria and fungi that can break down plastic in cold regions such as the Alps and the Arctic. A surprisingly large variety of microorganisms were discovered that also live on the surfaces of plastics. In the process Newly discovered, cold-adapted bacteria and fungi can digest biodegradable plastics at temperatures as low as 15 °C - well below the usual decomposition temperature of 30 °C, which consumes less energy.
From plastic waste to a valuable resource
Projects such as the EU-funded Recover project also combine microorganisms, enzymes, earthworms and insects to not only break down plastic, but also transform it into valuable raw materials. In this way, plastics can be decomposed and transformed into usable biomass.
Biological recycling of plastic can be a valuable addition to the circular economy. In addition as yet undiscovered microorganisms and biocatalysts open up new ways of efficiently recycling plastic in the future. Biorecycling makes sense where conventional recycling methods have reached their limits and plastic has so far been lost without being utilised.
Source: Plastic is Fantastic Association
