Biodegradation of plastic polymers by fungi: a brief review

Abstract

Plastic polymers are non-degradable solid wastes that have become a great threat to the whole world and degradation of these plastics would take a few decades. Compared with other degradation processes, the biodegradation process is the most effective and best way for plastic degradation due to its non-polluting mechanism, eco-friendly nature, and cost-effectiveness. Biodegradation of synthetic plastics is a very slow process that also involves environmental factors and the action of wild microbial species. In this plastic biodegradation, fungi play a pivotal role, it acts on plastics by secreting some degrading enzymes, i.e., cutinase`, lipase, and proteases, lignocellulolytic enzymes, and also the presence of some pro-oxidant ions can cause effective degradation. The oxidation or hydrolysis by the enzyme creates functional groups that improve the hydrophilicity of polymers, and consequently degrade the high molecular weight polymer into low molecular weight. This leads to the degradation of plastics within a few days. Some well-known species which show effective degradation on plastics are Aspergillus nidulans, Aspergillus flavus, Aspergillus glaucus, Aspergillus oryzae, Aspergillus nomius, Penicillium griseofulvum, Bjerkandera adusta, Phanerochaete chrysosporium, Cladosporium cladosporioides, etc., and some other saprotrophic fungi, such as Pleurotus abalones, Pleurotus ostreatus, Agaricus bisporus and Pleurotus eryngii which also helps in degradation of plastics by growing on them. Some studies say that the degradation of plastics was more effective when photodegradation and thermo-oxidative mechanisms involved with the biodegradation simultaneously can make the degradation faster and easier. This present review gives current knowledge regarding different species of fungi that are involved in the degradation of plastics by their different enzymatic mechanisms to degrade different forms of plastic polymers.

Ten decadal advances in fungal biology leading towards human well-being

“…Fungi degrade plastic polymers with extracellular enzymes, and the breadth of such processes has been recently reviewed by Srikanth et al ( 2022 ), Temporiti et al ( 2022 ) and Devi et al ( 2016 ). The summarized findings from those reviews are given in Table 7 .…”

Plastic-inhabiting fungi in marine environments and PCL degradation activity

“…Cladosporium included 13 PCL-degrading species of which four and nine had strong and moderate PCL-degrading activity, respectively. Prior research confirmed that several Cladosporium strains effectively degraded other substrates, such as polyurethane (Bonhomme et al 2003 ; Brunner et al 2018 ; Srikanth et al 2022 ). Therefore, Cladosporium species could degrade plastic wastes in the marine environment.…”

Fungi-based Biomimetic Approach to Address Plastic Pollution: A Developing Nation's Perspective

“…Incorporation of reinforcements in fungal biocomposites is also a less explored area of research and provides a unique opportunity for startups to come up with novel composites that can be used to create insulation panels with improved characteristics. Recently, the discovery of plastic degrading fungi species has increased the significance of fungi's role in reducing plastic pollution [68]. The process of degradation of plastic by fungi is also in the nascent stage and it needs to be standardized before it becomes a tangible solution [69].…”