Review on Efficacy of Microbial Degradation of Polyethylene Terephthalate and Bio-upcycling as a Part of Plastic Waste Management

Poly (ethylene terephthalate) (PET) is a very common and excessively used plastic polymer. The accumulation of PET waste in the environment has led to increasing global concerns because of the extremely low degradation properties of this polymer. Only a few ways have been identified to biologically degrade PET. Although none of these methods has been brought into use industrially, but the evolution of microbes leading to abilities to degrade certain polymers is quite promising and gives us the opportunity to identify and utilize these properties to solve the long time existing problem of plastic waste. Different types of PET hydrolases have been isolated from fungi as well as bacteria and some of them have shown remarkable degradation of crystalline PET with upto 50% weight loss and in about two to three weeks time. Some of the PET hydrolases have been characterized to be stable at high temperatures of 50 to 70°C which is an advantage for industrial application as efficient degraders of PET. This review article gives a brief overview on the various methods of PET degradation and focuses mainly on the microbes which have been identified to be capable of degrading PET. The enzyme involved in degradation for each microorganism is being explored in order to get a better understanding of the degradation mechanism. In addition, current status of bio-upcycling of PET is being discussed which is an alternative way of managing the ever increasing build of plastic waste.