Study on the Microbial Degradation Behavior on Mocroplastic Using Mixed Bacterial Consortium

초록

Emerging the global microplastic pollution in the most of environmental media including the maritime, freshwater, and terrestrial environment, many scientific researchers have investigated to isolate specific microbes, capable of utilizing plastic as the carbon and energy source and consequently degrade them from the actual environmental system. This study examined the biodegradation behavior of the various types of microplastic (i.e., Polyethylene (PE), Polystyrene (PS), and Polypropylene (PP)) decomposed by mixed bacterial consortia (mainly composed of Bacillus sp., Clostridium sp., and Lysinibacillus sp., and Paenibacillus sp.), which have been collected from the municipal waste dump located in Incheon, Korea (Park and Kim, 2019). Resultingly, biologically decomposed microplastics have a relatively abundant carbonyl groups on the microplastic surface and eluted organic compounds with a long carbon chains compared to the control, prepared with same manner except for the inoculation of bacterial isolates, implying that these bacterial consortium play an important role in that process. Meanwhile, the initial concentration of bacterial inoculum and labile organic substance (e.g., glucose) have a significant effect on microplastic biodegradation. In particular, increasing glucose concentration has been contributed to the promoting the formation of carbonyl groups on the microplastic surface, while decreasing the weight loss of plastic.