Microbial degradation of low density polyethylene (LDPE): A review

Abstract

Biodegradation is considered to take place throughout three stages: biodeterioration, biofragmentation and assimilation, without neglect the participation of abiotic factors. However, most of the techniques used by researchers in this area are inadequate to provide evidence of the final stage: assimilation. In this review, we describe the different stages of biodegradation and we state several techniques used by some authors working in this domain. Validate assimilation (including mineralization) is an important aspect to guarantee the real biodegradability of items of consumption (in particular friendly environmental new materials). Since LDPE is considered to be practically inert, efforts were made to isolate unique microorganisms capable of utilizing LDPEs. Recent data showed that biodegradation of LDPE waste with selected microbial strains became a viable solution. Among biological agents, microbial enzymes are one of the most powerful tools for the biodegradation of LDPEs. Activity of biodegradation of most enzymes is higher in fungi than in bacteria. It is important to consider fungal degradation of LDPE in order to understand what is necessary for biodegradation and the mechanisms involved. This requires understanding of the interactions between materials and microorganisms and the biochemical changes involved. Widespread studies on the biodegradation of LDPEs have been carried out in order to overcome the environmental problems associated with LDPE waste. This paper reviews the current research on the biodegradation of LDPEs and also use of various techniques for the analysis of degradation in vitro.