Microbes in Plastic Degradation

Due to increasing production of plastic and its piling up is a critical concern hence ways to degrade the plastic needs to be sought out. Microplastics (MPs) of the size of micron or less have been found everywhere, even in human blood, highlighting the adversity of the situation. Natural and microbial degradation mechanisms of MPs, focusing on polyethylene (PE) and polyethylene terephthalate (PET) have been explored by the study. Natural degradation is hindered by stability and hydrophobic properties of the polymers. Despite recycling efforts, a significant portion of PET waste ends up in landfills and the environment, posing threats to ecosystems and organisms. MPs are ingested by aquatic organisms, serve as substrates for unwanted microbes, and act as vectors for toxic chemicals. Atmospheric and aquatic fluxes contribute to the transport of MPs from production sources to marine environments. Microorganisms like bacteria, can degrade plastic polymers. Bacterial cultures are found to be effective in degrading MPs through extracellular and intracellular enzyme systems. Bacterial degradation of PE and PET has been demonstrated in laboratory conditions, with varying removal efficiencies and degradation durations. Abiotic factors like oxygen and light help in the PE degradation, while hydrolase enzymes are involved in PET degradation. For effective plastic management, a cyclic bioeconomy based method is necessary, which involves reconsideration of the entire value chain of plastic. Future-proofing plastic waste management requires delinking plastic production from fossil-based raw materials and energy sources. Additionally, addressing agricultural and food waste losses can contribute to reducing the carbon footprint associated with plastic production. Overall, understanding the microbial degradation of plastics offers promising avenues for combating plastic pollution and achieving a more sustainable plastic waste management system.