Recent advances in the bio-remediation of persistent organic pollutants and its effect on environment

This paper presents a comprehensive review of the current state of research activities on the application of biodegradation/bioremediation for removing persistent organic pollutants (POPs) such as pesticides, PCBs, PAHs and PPCPs from wastewater. Several potential enzymes have been reported from various microorganisms, which breakdown the complex compounds through biodegradation, biostimulation or bioaugmentation process. Various microorganisms, harbouring numerous plasmids and catabolic genes, acclimatize to these environmentally unfavourable conditions by gene duplication, mutational drift, hypermutation, and recombination. Genetic aspects of some major POP catabolic genes such as biphenyl dioxygenase (bph), hydroxylation, phosphotriesterases and oxygenase etc. assist in degradation organic pollutants. However with the advent of technological advancements in genetic engineering is being considered the possibility for the role of genetically modified organisms, metagenomics and metabolomics is being considered to develop low cost, effective and reliable method for detection, determination and removal of ultra-trace concentration of POPs. In addition, development in microbial fuel cell, nano-materials, biofilms and constructed wetlands augments the biodegradation process. Therefore, this review highlights the effect of POPs on the environment, health hazards, microbial degradation and its mechanism along with brief study of advanced oxidation process for wastewater treatment. (C) 2018 Elsevier Ltd. All rights reserved.