Abstract

  Plastic pollution is the crucial topic of concern at present and mainly 80% of polymers encompass the pollution. Because of inappropriate recycling, it is creating a detrimental impact on the ecosystems of our land and oceans. Many studies have been pursued on plastic biodegradation and found that the crystalline form of plastics actually degrades at different levels and it is a quite slow process. The microplastics are broken-down with exoenzymatic activities into smaller monomers and then easily get entered the cell wall of bacteria. These monomers then get assimilated inside to cells to form CO₂ and biomass.

  Plastic litter’s accumulation happens largely in marine environment and there is no area in the sea which is not affected by human influence. The micro and meso plastics get eaten-up by marine animals, resulting the release of toxic chemicals. The bacteria Citrobacter and Kosakonia are found in the gut of worm Tenebrio molitor and identified to degrade polyurethanes and polystyrene. Polyurethanes, polyethylene, polyethylene terephthalate, polystyrene, polyvinyl chloride and polypropylene are the preeminent polymers to be used in our economy. A few fungi and bacteria have been identified for the partial degradation of polymers e.g. Themofifida, Thermomonospora, Ideonella sakaiensis, Pseudomonas putida, microspora, Cladosporium and other species. The enzymes involved in the hydrolysis are tannase, MHETase, cutinases and other hydrolases enzymes. The new biodegradable plastics have also introduced in the market as they are easily attacked by microorganisms to degrade them in eco-friendly way. The cold environment microorganisms degrade the plastics are, Pseudomonas sp, Shewanells, Psychrobacter Aspergillus, vibrio sp, Rhodococcus etc. The actual biodegradation process for cold environment is not systematically proven yet. Some pathogenic species of bacteria can spread through “Plastosphere”, but their pathogenic evidence is still needed to verify.

  The metagenomic studies on Chryseobacterium and Parapedobacter identify the high average novelty scores indicating the new species to be involved in polymer biodegradation process. The deconvoluted genome sequences report that biodegradation occurs in the oxidative pathways by oxidising the NAD+ and ADH by monooxygenase to produce methyl acetate and also by transformation of acetyl- CoA via acetone. BP8 community is first time discovered as the promising source for environmental biotechnology, which has the great phenotypic potential and catalytic capabilities to degrade polymers including xenobiotics. Putative metabolic pathway is discovered by a novel microbial landscape to breakdown PE-PU-A copolymers and xenobiotics. New strategies could be designed to reduce plastic pollution for better environmental quality. The current biodegradability standards are insufficient to identify the pragmatic approach and to compare it with in the same time frame in actual marine environment. There are so many ways, we still need to explore to get the realistic solution in identical conditions applied for Lab and outer natural environment.

Keywords: Biodegradation; Polymers; Polyethene; Enzymes; Microbes; Environment; Marine; Standards

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Citation

Citation: Anju Kaushal. “New Initiatives are to be Enforced to Execute More Research on Thorough Degradation of Global Polymers Using Diversified Microbes/ Enzymes in the Eco-Friendly Way". Acta Scientific Microbiology 3.4 (2020): 97-108.

Copyright

Copyright: © 2020 Anju Kaushal. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.