Breakdown of PET plastic possible in few hours by an enzyme

Dr. Aparna Deshpande

The rapidly increasing production of disposable plastic products overwhelms the world’s ability to deal with them. Plastic pollution is most visible in developing Asian and African nations along with the developed world countries with low recycling rates. A team of researchers at Leipzig University have now discovered a highly efficient enzyme that degrades PET in record time. They came across an enzyme PHL7 in a compost heap. It has come up as an effective  biological solution for PET degradation. As per the findings published in  the scientific journal ChemSusChem also the cover topic  of the edition this is the most sustainable solution till date for plastic remediation. Enzymes are used by bacteria to decompose plant parts in nature. Polyester-cleaving hydrolases is a class of enzyme known for plastic degradation from quiet sometime. The enzyme LCC, discovered in Japan in 2012-13, is considered to be a predominantly effective “plastic feeder.” The team headed by Dr. Christian Sonnendecker, an early r from Leipzig University, was looking  for previously undiscovered examples of these class of enzymes as part of the EU-funded projects MIPLACE and ENZYCLE. They got the answer they were looking for in a compost heap from a cemetery in Leipzig. The researchers came across the blueprint of an enzyme that decomposed PET at record speed in the laboratory.

In the  performed experiments, the researchers added PET to a container with an aqueous solution containing either PHL7 or LCC, the pioneer in PET decomposition. Then they measured the amount of plastic that was degraded in a given period of time was measured the values  were compared with each other. In 16 hours, PHL7 caused the PET to decompose by 90 percent while, LCC managed a degradation of just 45 percent.  PHL7 enzyme is twice as active as the gold standard among polyester-cleaving hydrolase explains Dr. Sonnendecker. To be more specific in analytical performance PHL7 broke down a plastic punnet—the kind used for selling grapes in supermarkets in less than 24 hours. The researchers explains that a single building block in the enzyme is responsible for this above-average activity. At the site where other previously known polyester-cleaving hydrolases contain a phenylalanine residue, PHL7 carries a leucine.

The conventional recycling methods  rely mostly on thermal processes where the plastic waste is incinerated at high temperatures. Enzymes, on the other hand require an aqueous environment and a temperature of 65 to 70 degrees Celsius. An added advantage of  enzymes is they break down the PET into its components terephthalic acid and ethylene glycol, which can be reused to produce new PET resulting in a  controlled closed cycle. So far biological PET recycling has only been tried and  tested in France. The researchers at Leipzig hope that the newly discovered enzyme PHL7 can advance biological recycling in practice and are looking for developing this technology at industrial scale. They are confident that the higher speed will significantly reduce recycling costs. Over the next couple of years, they aim to create a model that will make it possible to quantify the economic benefits of their rapid biological recycling process more precisely. The scientists at the Institute also want to elucidate the structure and function of the enzymes using NMR spectroscopy. They are also working on a new pre-treatment method to solve the main problem statement i.e the more crystalline plastic. Biological recycling: PET decomposition by enzymes has successfully worked on amorphous PET is used in things like fruit packaging. Studies are in progress for the more crystalline plastics like PET bottles and food storage containers.

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Dr. Raghunath Mashelkar

Dr. Mashelkar is only the third Indian engineer to have been elected (1998) as Fellow of Royal Society (FRS), London in the twentieth century. He was elected Foreign Associate of US National Academy of Science (2005) and also National Academy of Engineering (2003), Associate Foreign Member, American Academy of Arts & Sciences (2011), Fellow of Royal Academy of Engineering, U.K. (1996), Foreign Fellow of Australian Technological Science and Engineering Academy (2008), Corresponding Member of Australian Academy of Sciences (2017), Fellow of World Academy of Arts & Science, USA (2000), Fellow of US National Academy of Inventors (2017), the first ever Indian from India to be elected and TWAS-Lenovo Science Prize (2018), which is the highest science award of The World Academy of Science.

In 2006, he received the ‘Star of Asia’ Award at the hands of former President of USA, George Bush (Sr). The President of India honoured Dr. Mashelkar with three of the highest civilian awards, namely Padmashri (1991), Padmabhushan (2000) and Padma Vibhushan (2014).

Prof. Satishchandra Ogale

Prof. Satishchandra B. Ogale has had a long 40 years of experience in higher education and research.  He has over 500 publications in international journals, three co-edited books with Springer, Wiley and Elsevier, and 10 granted US patents based on research done in India. 
He is a Reviewer as well as Advisory Board member of many high impact International Journals and is also a popular science writer in regional language marathi.
He has won many Awards, Prizes, and National and International recognitions. He has given numerous invited, plenary and keynote talks in National and International conferences and has supervised over 65 Ph.D. students. 
Prof. Ogale has been a Visiting Professor/ Scientist in many institutions in the USA and Europe on several occasions.

Anupama Engineer

She has previously worked as a Scientist at Agharkar research Institute and at higher management level at Thomas Baker Bioscience Private Limited. She has also taught graduate and post graduate students in Biotechnology & Microbiology during her tenure as a lecturer in Royal College, Mumbai and as a Counselor for IGNOU Biotechnology course. Anupama, is a multitasker with few roles like, entrepreneur, Scientist, manager, a doting mother and many more. Teaching and educating is her passion and she takes every effort to encourage fundamental learning. Anupama holds a vast experience in Start-up processes.

Dr Smita Chaturvedi
Smita is an experimental condensed matter physicist. The quest for multifunctional materials motivates her. Smita finished her PhD from RDVV Jabalpur and BARC Mumbai in the year 2002 and worked as a research associate in IIT Mumbai and Oakland University, Michigan. Smita was awarded as a Fulbright Nehru Academic and Professional excellence fellow in 2018-19. Smita holds more than a decade of research and teaching experience. She possesses good knowledge about education system and research opportunities in India as well as abroad. Music and gardening are her mindful meditations.
Dr. Priyadarshini Karve
Dr Priyadarshini Karve has worked in the areas of household energy, decentralised waste-to-fuel technologies, climate change mitigation and adaptation, sustainable and climate-ready urbanisation, etc. She runs her own social green enterprise Samuchit Enviro Tech in Pune, focused on enabling access to sustainable products and services. She is also a co-founder of OrjaBox, a startup promoting solar thermal technologies. Dr Karve is a Founder Member of Clean Energy Access Network (CLEAN - a multi-state society of decentralised renewable energy practitioners and entrepreneurs) and Cleaner Cooking Coalition (CCC - an international organisation focused on promoting user-centric cooking energy technologies that are good for health as well as climate). She is also the National Convener of Indian Network on Ethics and Climate Change (INECC - focused on climate justice issues and working to bring people's voices in policy choices). Her work has been recognised by several national and international awards and honours.
Sanjay Khare
Sanjay Khare ,after his graduation in Electrical Engineering from Indian Institute of Technology, Kanpur, in 1986 has been associated with major Japanese & European Automotive OEMs in Indian Subcontinent for 35 years . Widely travelled across Europe & Asia , he has held positions across diverse functions of Automotive Corporations.
In his current role as Board Member and Vice President at Skoda Auto Volkswagen India , he is Chief Sustainability Catalyst to guide actions at Skoda Auto Volkswagen India along with the sister brands Audi, Porsche & Lamborghini.
He leads an active Climate Resilience program where the automotive major in India has already achieved Zero Waste to Landfill, Water Positive & Zero liquid Discharge Certification, Zero Accidents , targeting an 18.5 MW of installed Roof Top Solar plant at a single Automotive site in India in 2021 and fully Carbon Neutral Production by 2025.
Sanjay has done his Executive MBA from Management development Institute ,Gurgaon specialising in Strategy & Marketing . He has active interests in driving Cultural Change, Competency building , Human Motivation topics while adopting/ innovating the technological advancements and total quality revolution.He is also a Qualified Independent Director registered with Ministry of Corporate Affairs, Govt. of India. An active speaker on Automotive & Sustainability topics on National & International forums.
In personal life, he is an Endurance Cyclist having participated in many adventure ride expeditions . He also spends his time in developing mastery on Indian Classical Music instrument Sitar.