Biodegradation of Polythene waste through soil Bacteria: A Review

Polyethylene waste accumulating in the environment poses an ever increasing ecological threat. They are usually a polymer of ethylene which forms an essential part in our everyday life. They are used in various sectors for wide applications such as packaging materials as films or sheets, as insulators or as consumer products and others. There is an increasing demand for these polymers; with almost 500 billion to 1 trillion tonnes have been used routinely worldwide. They consist of high molecular hydrocarbons with complex structures which can?t be degraded easily and their disposals have aroused a great environmental threat. It takes nearly about thousand years for efficient decomposition of these polymers in nature. Widespread studies on biodegradation of plastics have been carried out to overcome the environmental problem associated with these synthetic plastic wastes. This review focus on recent findings on the isolation of synthetic polymer degrading bacterium from soil, the discovery of new degrading enzymes and the cloning of genes for biodegradation. The soil bacteria release the extracellular enzymes such as lignin peroxidase, manganese peroxides to degrade the polythene but the thorough characterization of these enzymes in relation to polythene degradation is still needed to be carried out. In addition, efficient polythene degrading soil bacteria need to be screened from various sources.