Morphological modification of low-density polyethylene for enhanced Phanerochaete chrysosporium surface bioerosion

Abstract

Disposal of end-of-life low density polyethylene (LDPE) in landfill structures poses an ecological threat through leaching, fragmentation, and additive migration. The present study examines the mycodegradation of morphologically modified low- density polyethylene (LDPE) films by Phanerochaete chrysosporium, a lignolytic basidiomycete. Three physicochemical treatments were employed: thermo-oxidation, chemical etching, and synthetic leachate. Surface area imaging over 6 days revealed bioerosion, qualifying P. chrysosporium as a suitable agent for LDPE degradation. Analysis of crystallinity indices showed that thermo-oxidation and chemical etching induced conformational changes to the polymer surface, increasing surface area reduction by 19% and 22% respectively. Synthetic leachate (SL) was associated with a 36% increase in surface area reduction. In combination, the three treatments achieved a 99% increase in surface area reduction. These trends were corroborated by gaseous evolution in parallel, attributable to the metabolization of fungal isolates. Electrospray Ionization Fourier Transform (FTMS + pESI) profiles observed signs of leachate remediation and organic byproducts. A molecular mechanism for degradation was subsequently proposed based on SL composition.