Researchers Achieve Biodegradation of Plastic Films with Soil Microbes
30 November 2018
Our world is contaminated with plastic waste. It does not affect our oceans but our agriculture soil as well. Many farmers are using PE mulch film to cover their crop to combat weeds, increase soil temperature and keep the soil moist, thereby increasing overall crop yields. However the removal of mulch film after harvest is impossible. This small parts of plastic mulch is left on the soil and contaminated the soil. Film residues in soils decrease soil fertility, interfere with water transport and diminish crop growth.
Researchers at ETH Zurich and the Swiss Federal Institute of Aquatic Science and Technology (Eawag) have now shown in a study that demonstrate that soil microbes degrade films composed of the alternative polymer poly(butylene adipate-co-terephthalate) (PBAT). Their work has just been published in the journal Science Advances.
In the research project coordinated by Michael Sander, Kristopher McNeill and Hans-Peter Kohler, former ETH doctoral student Michael Zumstein succeeded in demonstrating that soil microorganisms metabolically utilized the carbon in the PBAT polymer both for energy production and also to build up microbial biomass.
The researchers used PBAT material that was custom-synthesized from monomers to contain a defined amount of the stable carbon-13 isotope. This isotope label enabled the scientists to track the polymer-derived carbon along different biodegradation pathways in soil.
Using isotope-sensitive analytical equipment, the researchers found that the carbon-13 from PBAT was not only converted into carbon dioxide as a result of microbial respiration but also incorporated into the biomass of microorganisms colonizing the polymer surface.
“This research directly demonstrates, for the first time, that soil microorganisms mineralize PBAT films in soils and transfer carbon from the polymer into their biomass,” says Michael Sander, Senior Scientist in the Environmental Chemistry Group in the Department of Environmental Systems Science at ETH Zurich. Their work truly shows the true definition of biodegradable plastic not only breaking down plastic into small fragment and still exist in the environment.
Source: ETH Zurich https://polymer-additives.specialchem.com/news/industry-news/researchers-biodegradation-plastic-films-soil-microbes-000215578?lr=ipa1808463&li=200160570&utm_source=NL&utm_medium=EML&utm_campaign=ipa1808463&m_i=vHKt7JLvejI6XS4oU5MwjZbVt%2B%2B8sipqxNk0w2rms3WXBteLDEb96Yngp4fOWTZ%2BSiQeFrLKPnzZbwvpj2ROCpNkctLZvY