Study on biodegradation of polyethylene by microorganisms isolated from Zhanjiang Mangrove Reserve

Abstract

Zhanjiang Gaoqiao Mangrove Reserve is one of the largest mangrove reserves in China, and its unique ecosystem makes the mangrove rich in microbial resources. In this study, the sediments from Zhanjiang Gaoqiao Mangrove was used as the samples, and polyethylene (PE) was used as the sole carbon source in the carbon-free medium. The microorganisms in the mangrove sediment were enriched, isolated, purified to obtain PE-degradable bacteria; The species of PE-degrading bacteria were determined by morphological analysis, biochemical identification and molecular identification; The degradation ability of the strain to PE was evaluated by weight loss rate and Fourier transform infrared spectroscopy (FTIR). The obtained results presented three strains of pseudo-degradable bacteria S1-1, S1-2 and S1-3, which belonged to Pseudomonas aeruginosa, Acinetobucter venetianus and Klebsiella pneumoniae, respectively. Among them, S1-3 had the best degradation effect, and the weight loss rate reached 4.25% after 120 days. The weight loss rates of S1-1 and S1-2 were 3.81% and 3.88%, respectively. Under the observation of FTIR, it was found that all three strains could change the internal structure of PE. This study laid a foundation for the verification of PE degradation and provided a reference for the bioremediation of PE pollution in the environment.