**Research Team Led by Ryoo Chung-min at the Korea Research Institute of Bioscience and Biotechnology( KRIBB)**
A research team led by Ryoo Chung-min, Director of the Infectious Disease Research Center at the Korea Research Institute of Bioscience and Biotechnology (KRIBB), has discovered an enzyme in the gut of the greater wax moth that can degrade plastic. To mass-produce this plastic-degrading enzyme, they have established a system using yeast and insect cells.
According to the United Nations Development Programme (UNDP), the global recycling rate for plastics is only 9%. While South Korea’s recycling rate is slightly higher at 16.8%, most waste is still handled by landfilling. Plastics discarded in landfills do not decompose for hundreds of years, causing severe environmental pollution.
To address the plastic waste problem, the scientific community is exploring biodegradable plastics. These aim to maintain the durability and strength of conventional plastics while enabling rapid decomposition when buried. However, existing biodegradable plastics have yet to match the properties of conventional plastics and remain costly to produce.
The KRIBB team has identified enzymes in the greater wax moth that oxidize plastic, offering a way to decompose not just biodegradable plastics but also conventional plastics rapidly. This “biological plastic degradation” technology is environmentally friendly and can also be applied to the treatment of existing plastic waste, making it increasingly significant.
Greater wax moths consume wax, which shares a similar structure to plastics and has been a focus for biological plastic degradation methods. In 2019, the research team first demonstrated that the enzyme cytochrome P450 secreted by these moths could digest polyethylene, a type of plastic.
Director Ryoo stated, “While moths can decompose plastic, they can only do so for two weeks of their lifecycle, making this method commercially unfeasible. Instead, we’ve developed a method to mass-produce the moth’s enzyme and apply it directly to plastics.”
The team successfully mass-produced the plastic-degrading enzyme by inserting the cytochrome P450 gene into yeast and culturing insect cells. The enzyme produced by these cells effectively decomposes plastics even outside the insect’s stomach.
Furthermore, using artificial intelligence (AI) simulations, the team uncovered the plastic degradation mechanism of cytochrome P450 and enhanced its degradation efficiency through genetic modifications.
Director Ryoo highlighted, “This research opens new possibilities for treating plastic waste using insect-derived enzymes. We’ve clarified the action mechanism of plastic-degrading enzymes and confirmed the practical potential of using enzymes for plastic waste treatment.”
The study’s findings were published on October 23rd in the international journal, Journal of Hazardous Materials.
Reference:
Journal of Hazardous Materials (2024), DOI: https://doi.org/10.1016/j.jhazmat.2024.136264