IJEP 45(3): 212-211 : Vol. 45 Issue. 3 (March 2025)
Arpana Pallavi Palanna* and D. Sayantan
Christ University, Department of Life Sciences, Bengaluru – 560 029, Karnataka, India
Abstract
Low-density polyethylene (LDPE) is widely used in food packaging and agricultural mulching, but its disposal creates harmful macro-, meso- and microplastics. To address this, LDPE has been treated to become biodegradable. The treatment involved dissolving LDPE in trichloroethylene and treating it with starch, hydrogen peroxide, nitric acid and acetic acid, reducing its crystallinity from 48.48% to 32.98% through single (T), double (TT) and triple (TTT) treatments. This 15.5% decrease in crystallinity enhanced polymer degradation. When LDPE microplastics with 40.02% crystallinity (TT) were tested on Eudrilus eugeniae earthworms, they showed a lower mortality rate compared to other treated and untreated LDPE. The 40.02% crystallinity LDPE exhibited hydroxyl and carboxylic functional groups. Treated LDPE (TT) introduced to earthworm casts showed microbiota, including Mycobacterium and Rozellomycota, known for polyethylene degradation. Additionally, microbial examination of treated LDPE revealed Aeromonas and Pyrenochaetopsis leptospora in the earthworm gut, potential LDPE degraders. X-ray differaction (XRD) analysis and Fourier transform infrared (FTIR) spectra indicated distinct degradation patterns. After 21 days with Eudrilus eugeniae, treated LDPE’s crystallinity decreased from 40.02% to 22.84%. This study highlights the significance of oxidized treated LDPE for microbial colonization and degradation, supporting Eudrilus eugeniae survival and improving soil biota health.
Keywords
Low-density polyethylene, Thermo-oxidative reaction, Eudrilus eugeniae, Cast gut microflora
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