Microbial degradation of low density polyethylene by Exiguobacterium sp. strain LM-IK2 isolated from plastic dumped soil.

Low-Density Polyethylene (LDPE) is one of the significant environmental pollutants as it is resistant to natural degradation. In this study, we reported the LDPE-degrading bacterial strain i.e., Exiguobacterium sp. strain LM-IK2 isolated from plastic dumped soil which shows potential degradation capability. The percent weight loss of LDPE was calculated as - 5.70 ± 0.7 after 90 days of incubation in a carbon-free MSM medium. The Field Emission Scanning Electron Microscopy (FE-SEM) analysis shows that LDPE films show slight surface disruption after treatment with bacteria. The Fourier Transform Infrared Spectroscopy (FTIR) revealed the chemical changes in LDPE films e.g., formation and reduction of typical carbonyl peaks after incubation with bacteria. The X-Ray Diffraction (XRD) analysis displayed an increase in percent crystallinity, with a slight change in total carbon content. Genetic analysis showed the presence of Laccase (167 bp) and Alkane Hydroxylase (330 bp) genes that are responsible for LDPE degradation. Thus, Exiguobacterium sp. strain LM-IK2 has the potential to degrade LDPE and could be further explored to improve its efficiency in the bioremediation of LDPE.