

The enzymatic degradation of post-consumer plastic waste is emerging as a novel and environmental benign and sustainable alternative to conventional recycling processes. Recently, it has been shown that synthetic polyesters such as PET can be completely hydrolysed by microbial enzymes at mild reaction conditions in aqueous media within short reaction times. The resulting monomers can be recovered and reused. By the generation of more powerful biocatalysts employing protein engineering techniques and an optimization of the bioprocess parameters, biocatalytic recycling of PET can be further developed towards an industrial application.

Fig. 1: Surface of a polyester hydrolase with a PET model compound docked within the substrate groove. Green, carbon atoms; red, oxygen atoms; green and pink surface, lipophilic and hydrophilic surface patches, respectively. The enzyme catalyses the hydrolysis of ester bonds in the PET polymer (R. Wei, Leipzig University).

Fig. 2: Scanning electron microscopy images of low crystalline PET films degraded by a polyester hydrolase. (a) Untreated PET, (b) with 10.4% weight loss, (c) with 29.2% weight loss, and (d) with 97.5% weight loss. Arrows indicate holes in the PET film (R. Wei, Leipzig University).

Fig. 3: Hydrolysis of low crystalline PET in an enzyme bioreactor. The monomers can be separated and reused (Barth M et al., J Mem Sci 494, 182-187, 2015).
The comPETence center provides your organisation with a dynamic, cost effective way to promote your products and services.

magazine
Find our premium articles, interviews, reports and more
in 3 issues in 2023.