Cytobacillus sp. Strain HMBC3 from Saudi Arabian Soil Degrades Low-Density Polyethylene

Considering the dangerous effects on the environment of commonly used packaging materials like low-density polyethylene (LDPE), finding a practical and environmentally safe method for decomposing plastics is crucial. In this study, a bacterial strain (HMBC3) was identified in plastic-contaminated soil samples from eastern Saudi Arabia and showed potential for breaking down LDPE, as revealed by results from weight loss, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and gas chromatography-mass spectrometry (GC-MS). HMBC3 was discovered among bacterial isolates in a mineral nutritional medium (MNM) enhanced with LDPE as the only carbon and energy source. The strain caused changes in the media pH from 7.0 ± 0.03 to 6.23 ± 0.05, while the LDPE also showed 20.4% weight loss. In addition, the 16S rRNA gene similarities revealed a 98.9% homology between HMBC3 and Cytobacillus sp., indicating their close similarity. The high efficiency of strain HMBC3 in biodegrading plastic could potentially lead to its widespread development as an eco-friendly way to eliminate or minimize environmental plastic pollution.