The increasing accumulation of low-density polyethylene (LDPE) waste in the environment poses a growing threat to natural ecosystems due to its resistance to degradation. In this study, bacterial isolates were screened for their LDPE-degrading capability. Four distinct bacterial strains were isolated based on their ability to degrade polyethylene, out of which the strain identified as Serratia nematodiphila demonstrated the highest LDPE degradation activity of 1.53%. The other strains identified as Escherichia coli, Priestia aryabhattai, and Raoultella ornithinolytica also demonstrated LDPE degradation activity ranging from 0.36 to 1.11%. The LPDE degradation led to surface erosion and microbial colonization. The attenuated total reflectance-Fourier transform infrared analysis also indicated bond cleavage through changes in characteristic functional groups of the LDPE strip. The high-performance liquid chromatography-tandem mass spectrometry analysis detected multiple oxidative degradation byproducts, including polyethylene glycol derivatives, esters, and fatty acids in the synthetic media suggesting microbial assimilation of LDPE fragments as carbon sources. This study demonstrates the ability of bacterial strains isolated from the river water ecosystem to utilize the UV-pretreated LDPE as the sole carbon source for potential use in plastic waste management.