Role of Enzymes in the Remediation of Polluted Environments

Environmental pollution is growing more and more due to the indiscriminate and frequently deliberate release of hazardous, harmful substances. Research efforts have been devoted to develop new, low-cost, low-technology, eco-friendly treatments capable of reducing and even eliminating pollution in the atmosphere, the hydrosphere and soil environments. Among biological agents, enzymes have a great potentiality to effectively transform and detoxify polluting substances because they have been recognized to be able to transform pollutants at a detectable rate and are potentially suitable to restore polluted environments. This brief review will examine some classes of pollutants and enzymes capable of transforming them effectively into innocuous products. Particular attention will be devoted to pollutants with a high polluting potential such as polyphenols, nitriles, PAHs, cyanides and heavy metals. The enzymatic processes developed and implemented in some of these detoxification treatments will be examined in details. The main advantages as well as the main drawbacks that are still present in the extensive application of enzymes in the in situ restoration of polluted environments will be discussed.