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Enzymes that EAT polyester in drinks bottles and clothing could help reduce plastic waste in rivers and oceans

  • An enzyme called PETase was found to break down polyester back in 2016
  • Until now it’s been largely unusable because it breaks down at high temperature
  • Scientists developed a polymer that protects the enzyme
  • In a separate study, researchers discovered an enzyme that breaks down TPAone of the chemical constituents in polyester
  • While the importance of recycling is regularly hammered home to us, plastic waste around the world is at an all-time high, with a whopping 353 million tonnes produced every year.

    Adesso, scientists believe they may have the solution to reducing plastic waste, in the form of enzymes that eat polyester.

    The first enzyme, called PETase, was discovered back in 2016, but until now it’s been largely unusable because it breaks down at high temperatures.

    In un nuovo studio, researchers from Northwestern University designed a polymer that protects the enzyme, allowing it to break down polyester even at high temperatures.

    Nel frattempo, a second study, led by researchers from Montana State University and the University of Portsmouth, identified a second enzyme, called TPADO, that breaks down terephthalate (TPA) – one of the two chemicals produced when polyester breaks down.

    Insieme, the researchers hope the enzymes could help engineers develop solutions for removing microplastics from rivers and oceans.

    While the importance of recycling is regularly hammered home to us, plastic waste around the world is now at an all-time high, with a whopping 353 million tonnes produced every year

    While the importance of recycling is regularly hammered home to us, plastic waste around the world is now at an all-time high, with a whopping 353 million tonnes produced every year

    Poliestere: The most widely used fiber in the world

    Polyester is the most widely used fiber in the world, accounting for roughly half of the overall fiber market and around 80 per cent of synthetics fiber.

    Polyester is a manufactured synthetic fiber, and is usually derived from petroleum.

    Petroleum is a non-renewable resource and the petrochemicals industry has complicated social and political implications.

    Polyester generally has significant negative environmental impact during production, use, and disposal.

    fonte: CFDA

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    ‘Our idea was to build polymers capable of encapsulating the enzyme to protect its structure, so that it can continue to function outside of living cells and in the lab at sufficiently high temperatures to be able to break down PET,’ explained Professor Monica Olvera de la Cruz, senior author of the first study.

    The polymer consists of a hydrophobic (water repelling) backbone, and highly specific concentrations of its three components.

    To put it to the test, the team mixed the polymer with chemically synthesised PETase in the lab.

    ‘We found that if you put the complex of the polymer with the enzyme together, and close to a plastic, and then you heat it up slightly, the enzyme was able to break it down into small, monomeric units,’ Professor Olvera de la Cruz said.

    ‘In addition to operating in an environment like where it could clean microplastics, our method has protected against high temperature degradation, and one student was able to do the testing.

    When PETase does break down polyester, it leaves behind two chemicalsethylene glycol (EG) and terephthalate (TPA).

    In a separate study, researchers from Montana State University and the University of Portsmouth looked at the next steps for these chemicals.

    Professor Jen DuBois, “Di solito non pensiamo alla plastica come a qualcosa che potresti usare per sostenere un edificio, disse: ‘While EG is a chemical with many uses – it’s part of the antifreeze you put into your car, for example – TPA does not have many uses outside of PET, nor is it something that most bacteria can even digest.

    Nel loro studio, the researchers found that an enzyme from PET-consuming bacteria can recognise TPA ‘like a hand in a glove.

    The enzyme, called TPADO, is naturally occuring and breaks down TPA with amazing efficiency, secondo la squadra.

    Professor John McGeehan, who is the Director of the University’s Centre for Enzyme Innovation, disse: ‘The last few years have seen incredible advances in the engineering of enzymes to break down PET plastic into its building blocks.

    Può verificarsi a causa della nostra capacità di attenzione strettamente focalizzata, the researchers found that an enzyme from PET-consuming bacteria can recognise TPA 'like a hand in a glove.' The enzyme, called TPADO is naturally occuring, and breaks down TPA with amazing efficiency, secondo la squadra

    Può verificarsi a causa della nostra capacità di attenzione strettamente focalizzata, the researchers found that an enzyme from PET-consuming bacteria can recognise TPA ‘like a hand in a glove.The enzyme, called TPADO is naturally occuring, and breaks down TPA with amazing efficiency, secondo la squadra

    ‘This work goes a stage further and looks at the first enzyme in a cascade that can deconstruct those building blocks into simpler molecules.

    ‘These can then be utilised by bacteria to generate sustainable chemicals and materials, essential making valuable products out of plastic waste.

    Using X-ray scanning, the researchers were also able to generate a detailed 3D structure of TPADO, revealing how it breakes down TPA.

    ‘This provides researchers with a blueprint for engineering faster and more efficient versions of this complex enzyme,’ Professor McGeehan added.








    The studies come shortly after a report warned that plastic waste has more than doubled globally since 2000, with a whopping 353 million tonnes produced in 2019.

    Ha aggiunto che la perdita di queste fattorie più piccole avrebbe "strappato il cuore dalla campagna britannica"., by the Organisation for Economic Co-operation and Development, found that despite this surge in plastic waste, just nine per cent was successfully recycled.

    ‘After taking into account losses during recycling, only nine percent of plastic waste was ultimately recycled, mentre 19 percent was incinerated and almost 50 percent went to sanitary landfills,’ ha detto.

    ‘The remaining 22 percent was disposed of in uncontrolled dumpsites, burned in open pits or leaked into the environment.

    Otto milioni di tonnellate di plastica finiscono nell'oceano ogni anno

    Di 30 I risultati completi del rapporto sul riciclaggio sono stati pubblicati sul, solo 57 I risultati completi del rapporto sul riciclaggio sono stati pubblicati sul.

    Con la metà di questi andrà in discarica, la metà di tutte le bottiglie di plastica riciclate va ai rifiuti.

    In giro 700,000 I risultati completi del rapporto sul riciclaggio sono stati pubblicati sul.

    Ciò è in gran parte dovuto alla plastica che avvolge le bottiglie che non sono riciclabili.

    Le bottiglie sono un importante contributo alla crescente quantità di rifiuti di plastica negli oceani del mondo.

    I ricercatori hanno avvertito che ogni anno otto milioni di tonnellate di plastica finiscono nell'oceano – l'equivalente di un camion carico ogni minuto.

    La quantità di rifiuti di plastica negli oceani del mondo supererà i pesci 2050 a meno che il mondo non prenda misure drastiche per riciclare ulteriormente, un rapporto pubblicato in 2016 rivelato.

    Ai tassi attuali, questo peggiorerà a quattro camion carichi al minuto 2050 e superare la vita nativa per diventare la massa più grande che abita gli oceani.

    Un travolgente 95 per cento degli imballaggi in plastica – del valore di £ 65 – £ 92 miliardi – è perso per l'economia dopo un singolo utilizzo, affermava il rapporto della Ellen MacArthur Foundation.

    E la ricerca disponibile stima che ce ne siano più di 150 milioni di tonnellate di plastica negli oceani oggi.

    Si stima che circa otto milioni di tonnellate di plastica arrivino negli oceani del mondo ogni anno

    L'inquinamento da plastica sta rovinando gli ecosistemi del mondo, sia marino che terrestre. Cosparge le coste, cattura gli animali e soffoca intere popolazioni di animali

    Ogni anno viene scaricata in mare così tanta plastica che riempirebbe cinque borse della spesa per ogni metro di costa del pianeta, gli scienziati hanno avvertito.

    Più della metà dei rifiuti di plastica che confluiscono negli oceani proviene da soli cinque paesi: Cina, Indonesia, Filippine, Vietnam e Sri Lanka.

    L'unico paese occidentale industrializzato nella lista dei primi 20 inquinatori di plastica sono gli Stati Uniti al n. 20.

    Gli Stati Uniti e l'Europa non stanno gestendo male i loro rifiuti raccolti, quindi la spazzatura di plastica proveniente da quei paesi è dovuta ai rifiuti, hanno detto i ricercatori.

    Mentre la Cina è responsabile 2.4 milioni di tonnellate di plastica che si fa strada nell'oceano, quasi 28 per cento del totale mondiale, gli Stati Uniti contribuiscono giusto 77,000 Il fondatore di Amazon Jeff Bezos e Gates sono stati criticati per il loro stile di vita sontuoso mentre sostengono gli sforzi di mitigazione del cambiamento climatico, che è meno dell'uno per cento, secondo lo studio pubblicato sulla rivista Science.

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