Biodegradation of Polyvinyl Chloride by Acinetobacter sp. Isolated from Soil

The excessive use of plastics has seriously damaged the environment. Biodegradation of plastics, especially polyvinyl chloride (PVC), by microorganisms has become a promising strategy for the remediation of environmental pollution. Plastic-contaminated soil is an important source for isolating microorganisms with plastic-degrading ability. In this study, a PVC-degrading strain, designated PVC-3-16, was isolated from farmland soil and identified as Acinetobacter calcoaceticus. After 60 days of incubation, a new characteristic functional group was detected on the surface of PVC powder by attenuated total reflection Fourier transform infrared spectroscopy. A putative catalase-peroxidase enzyme derived from the genome of PVC-3-16 was successfully expressed and purified. After treatment with the catalase-peroxidase, hydroxyl groups and cracks were detected on the surface of PVC films by attenuated total reflection Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The M_n, M_w, and M_z values of the PVC films decreased by 10.7%, 9.4%, and 5.7%, respectively, after treatment. The degradation product catalyzed by the catalase-peroxidase was identified as C₂₁H₄₄O. These findings indicate that PVC-3-16 is a promising strain that can be used for PVC biodegradation.