Page 59 - Plastic News Issue August 2025
P. 59
BUSINESS NEWS
Study Offers Enzymatic Recycling
Cost Breakthrough
It is part of the PETzyme project, led by Profes-
sor José Manuel Martínez Costas (CiQUS) and Dr
Gemma Eibes (CRETUS).
Self-assembling spheres
Instead of purifying enzymes and attaching
them to solid supports, the Spanish team used
a single-step process to embed the enzyme di-
rectly into nanoscale compartments that form
naturally within E. coli bacteria. These protein
structures are based on a viral protein known as
cientists have developed a new technique muNS-Mi, which self-assembles into spheres in-
that could make enzymatic plastics recy- side the bacterial cells.
Scling more efficient and cost-effective by
embedding enzymes inside bacterial protein By tagging the enzyme with a short sequence, it
compartments. is automatically drawn into the protein compart-
ments during production. This IC-Tagging meth-
The novel method, published in the Journal of od eliminates the need for chromatography or
Hazardous Materials, addresses a major hurdle artificial carriers and results in enzymes that are
in enzymatic recycling – the difficulty and cost already immobilised and ready to use.
of producing, isolating and reusing the enzymes
that break down plastics such as PET. The study focused on a genetically optimised
version of the LCC (leaf-branch compost cuti-
With PET widely used in bottles and food trays, nase) enzyme, recognised for its ability to break
enzymatic recycling is claimed to offer a cleaner down PET efficiently. When tested on real post-
alternative to traditional methods, which often consumer plastics waste, including food packag-
involve high temperatures or harsh chemicals.
ing and lab trays, the enzyme achieved over 90
The work was carried out by researchers from per cent depolymerisation in less than 72 hours.
the Centre for Research in Biological Chemistry It could also be reused in multiple cycles with lit-
and Molecular Materials (CiQUS) and the Inter- tle loss of activity.
disciplinary Centre for Environmental Technolo-
gies (CRETUS), both part of the University of The scientists achieved over 90 per cent en-
Santiago de Compostela. zyme depolymerisation in less than 72 hours
August 2025 PLASTICS NEWS 59
