Challenges of polyethylene (PE) biodegradation – A perspective

Biotechnology Advances, vol. 85, pp. 108717

Abstract

PE brings convenience to people, as this plastic is cheap and performs in thousands of different forms. As PE with its high molecular weight and its stable CC bonds is recalcitrant. For decades, much work has been dedicated to screening microorganisms isolated from, e.g., soil, water, landfills, complemented with microbes from strain collections for their potential to degrade PE. However, no convincing evidence of the biodegradation of high molecular weight PE, without any pretreatment, has been presented so far. Here, we discuss potential mechanisms of PE biodegradation, especially the activation of the C-C-bond by specific or non-specific oxygenation reactions. We argue that it is doubtful that any enzyme can accept a non-water soluble, high molecular weight polymer in its highly oxidative active side. Hence, reactive oxygen species (ROS) could be a critical step toward biodegradation. Investigating the process of oxygenation may help to unravel the mystery of PE (bio)degradation. In this context, we further argue that reliable analytical methods are necessary, including stable and maybe even radioactive isotope-labelled polymers, to avoid ambiguous experimental results.

Authors 6

1. Luo Liu corresponding

   Beijing University of Chemical Technology

   Affiliation as printed

   State Key Laboratory of Green Biomanufacturing, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: liuluo@buct.edu.cn

2. Mengxin Zhang

   Beijing University of Chemical Technology

   Affiliation as printed

   State Key Laboratory of Green Biomanufacturing, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: 2024211036@buct.edu.cn

3. Haijun Xu

   Beijing University of Chemical Technology

   Affiliation as printed

   State Key Laboratory of Green Biomanufacturing, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: hjxu@buct.edu.cn

4. Zvjezdana Findrik Blažević

   University of Zagreb

   Affiliation as printed

   University of Zagreb Faculty of Chemical Engineering and Technology, Trg Marka Marulića 19, HR-10000 Zagreb, Croatia. Electronic address: zfindrik@fkit.unizg.hr

5. Hendrik Ballerstedt Aachen Institute of Applied Microbiology - iAMB WSS Research Centre "catalaix"

   RWTH Aachen University

   Affiliation as printed

   Institute of Applied Microbiology - iAMB, Aachen Biology and Biotechnology - ABBt, BioSc, WSS Research Centre "catalaix", RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany. Electronic address: hendrik.ballerstedt@rwth-aachen.de

6. Lars M. Blank corresponding Aachen Institute of Applied Microbiology - iAMB WSS Research Centre "catalaix"

   RWTH Aachen University

   Affiliation as printed

   Institute of Applied Microbiology - iAMB, Aachen Biology and Biotechnology - ABBt, BioSc, WSS Research Centre "catalaix", RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany. Electronic address: lars.blank@rwth-aachen.de