Molecular-Weight-Dependent Degradation of Plastics : Deciphering Host-Microbiome Synergy Biodegradation of High-Purity Polypropylene Microplastics by Mealworms

The biodegradation of polypropylene (PP), a highly persistent nonhydrolyzable polymer, by Tenebrio molitor has been confirmed using commercial PP microplastics (MPs) (Mn 26.59 and Mw 187.12 kDa). This confirmation was based on the reduction of the PP mass, change in molecular weight (MW), and a positive Δδ13C in the residual PP. A MW-dependent biodegradation mechanism was investigated using five high-purity PP MPs, classified into low (0.83 and 6.20 kDa), medium (50.40 and 108.0 kDa), and high (575.0 kDa) MW categories to access the impact of MW on the depolymerization pattern and associated gene expression of gut bacteria and the larval host. The larvae can depolymerize/biodegrade PP polymers with high MW although the consumption rate and weight losses increased, and survival rates declined with increasing PP MW. This pattern is similar to observations with polystyrene (PS) and polyethylene (PE), i.e., both Mn and Mw decreased after being fed low MW PP, while Mn and/or Mw increased after high MW PP was fed. The gut microbiota exhibited specific bacteria associations, such as Kluyvera sp. and Pediococcus sp. for high MW PP degradation, Acinetobacter sp. for medium MW PP, and Bacillus sp. alongside three other bacteria for low MW PP metabolism. In the host transcriptome, digestive enzymes and plastic degradation-related bacterial enzymes were up-regulated after feeding on PP depending on different MWs. The T. molitor host exhibited both defensive function and degradation capability during the biodegradation of plastics, with high MW PP showing a relatively negative impact on the larvae.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:58

Enthalten in:

Environmental science & technology - 58(2024), 15 vom: 16. Apr., Seite 6647-6658

Sprache:

Englisch

Beteiligte Personen:

He, Lei [VerfasserIn]
Ding, Jie [VerfasserIn]
Yang, Shan-Shan [VerfasserIn]
Zang, Ya-Ni [VerfasserIn]
Pang, Ji-Wei [VerfasserIn]
Xing, Defeng [VerfasserIn]
Zhang, Lu-Yan [VerfasserIn]
Ren, Nanqi [VerfasserIn]
Wu, Wei-Min [VerfasserIn]

Links:

Volltext

Themen:

Biodegradation
Gut microbiome
Journal Article
Microplastics
Molecular weight
Plastics
Polypropylene
Polypropylenes
Polystyrenes
Tenebrio molitor
Transcriptome

Anmerkungen:

Date Completed 17.04.2024

Date Revised 17.04.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1021/acs.est.3c06954

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM370529294