In 2010, researcher Sintawee Sulaiman began her first laboratory position at the University of Osaka in Japan.
She was given the job of adapting and testing an enzyme discovered by her colleagues in a mound of decomposing leaves in a park next to the university, named LCC - leaf-branch compost cutinase.
Ms Sulaiman was hopeful that LCC's ability to break down the waxy coating of leaves could also be used to degrade plastic.
The next day, she cut up an item of plastic packaging from a pair of headphones and let the pieces soak in water with some LCC samples overnight. By dawn, the plastic had changed in appearance.
"She remembers the plastic had some breaks or holes in it, which astonished her."
The plastic was PET, a polymer composed of tightly joined smaller chemical units known as monomers.
Polymers are all around us in nature; for instance, cellulose is the most widespread one and makes up the structure of trees and other plants.
Organic material is subjected to biodegradation as enzymes have evolved which are able to break down the chemical bonds in them.
Enzymes have only had a short period of time to become accustomed to plastics, thus limiting their capacity to break them down. Nonetheless, during the past twenty years, researchers have succeeded in speeding up this natural process.
Prof Alain Marty and his colleagues from the University of Toulouse in France have been carrying out this work.
For over eight years, LCCICCG has undergone a transformation, allowing them to become a certified PET specialist.
The efficacy of the enzyme is such that it is able to reduce PET polymer to its individual compounds, the ones used to produce new plastic. Prof Marty could be compared it to separating a string of pearls.
He explains how they use an enzyme that functions like a pair of molecular scissors - they breakthe bond between the pearls, freeing them and now, following a purification process, they can be sold once again.
He is currently the principal scientific officer at Carbios, based in Clermont-Ferrand in the middle of France, and has a demonstration facility there.
It resembles a microbrewery, with a big cylindrical reactor encircled by other machinery for handling PET plastic.
The most significant machine in operation deals with clothes that are high in polyester. PET plastic, which is polyester in its form, makes up approximately half of all fibres used in the manufacture of clothing globally.
In the end, a great number of these garments are burned or disposed of in landfills, frequently in lesser-developed countries.
At a large machine in Clermont-Ferrand, these garments are being given a second lease on life, going through a process of being shredded and having buttons as well as sequins taken off.
The remnants of fabric which have gone through this procedure are then inserted into a separate machine where they are formed into downy pellets. Large amounts of glistening splinters from plastic bottles pass through the same machine, with the end result of them being converted into pellets as well. This activity enlarges the area of the material and weakens the molecular ties of the plastic.
It is noteworthy that the pellets don't have to be composed entirely of PET. Pellets stemming from textiles may include other fabrics like cotton, and bottles may contain environmentally-friendly colorant. Even mixed plastics, like food trays, can be processed.
The company is currently in the process of rapidly expanding its operations. By 2025, they hope to open a recycling facility in northeastern France with the capacity of handling 50,000 tonnes of polyethylene terephthalate (PET) waste a year - which is equivalent to 300 million T-shirts or two billion bottles.
Carbios does not intend to be a recycler themselves, but rather will license their process to other firms, thus having the potential to propagate rapidly. They have established a consortium with influential brands such as Nestle, L'Oréal and PepsiCo.
This implies that minimal alteration is required as the same chemical monomers employed by plastic manufacturers are produced.
Despite the well-known nature of its product, it is also a challenge - since the indistinguishable chemicals, which are obtained from natural sources, come at a cost that is 60% higher than those from petrochemicals.
Emmanuel Ladent, Carbios' chief executive, predicts that the company will have an increased supply of feedstock over time.
The cost of raw materials will decrease, since we can now utilize feedstocks which would otherwise have been burned or disposed of in landfills.
He states that they will also gain from any carbon tax implemented in the future.
Carbios are not the only ones in the area - other research groups are using multiple enzymes to look into PET recycling.
However, none of these squads have reached the phase of escalating their system.
Prof Andy Pickford, from the Centre for Enzyme Innovation at the University of Portsmouth, has expressed his strong excitement towards Carbios' work. He mentioned that they are paving the path for others to be inspired, and if their efforts yield successful results, more people will become enthusiastic and join in.
He, however, is less hopeful concerning the possibility of recycling other sorts of plastic. It is likely that these materials will never be able to be recycled, and it would be beneficial to abstain from utilizing such plastics.
It is highly encouraged that progress be made given the statistics from the OECD that only a fraction of plastic, approximately 10% globally, is recycled. Annually, a shocking amount of the 400 million tonnes of plastic waste produced is sent to landfill sites, closing in on half of the total amount.
Businesses are increasingly utilizing more advanced technology.
Carbios is set to focus its attention on plastics that feature more intricate chemical constructions, such as nylon. According to Prof Marty, achieving this will require the use of a distinct enzyme.
Meanwhile, Sintawee Sulaiman, who initially noticed the LCC consuming plastic in 2010, is happy with the advancement her enzyme has made since the first time she fed it headphone packaging.
"I consider myself fortunate to have encountered LCC," she declares. "And I truly hope that it will be able to make a difference in the world - to make the world a better place."
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