Mushrooms - A Promising Candidate for the Biosorption of Heavy Metals from the Environment

Heavy metal pollution has become an emerging issue worldwide owing to its high toxicity, non-biodegradability and persisting nature. Thus, it shows high bioaccumulative ability in the living system that may lead to carcinogenicities and several health complications in humans, even at trace concentrations. Their genesis occurs via both natural as well as anthropogenic activities that have contributed to an unusual increase in the concentration of toxic heavy metals across the globe. Several conventional methods, namely chemical precipitation, ion exchange, and membrane filtration, are being implied for the elimination of recalcitrant metals persisting in the ecosystem. But these methods have their own shortcomings and offer many limitations when applied to large volumes and fewer metal concentrations. In this regard, an alternative treatment method is needed that will overcome major demerits while remediating pollutants at a large scale without generating any secondary pollutants. Hence, a variant of the sorption technique, i.e., biosorption, appeared as economical and eco-friendly alternative treatment technology which is characterized by utilizing a material of biological origin. Further, in this process, the binding of passive cations might occur through living or nonliving biomass and aid in the elimination of contaminants from the aquatic system. The origin of biosorbents may vary in terms of the different microorganisms used. However, the biomass of macrofungi or mushrooms has been apprehended as a reassuring class of low-cost adsorbents in effacing toxic ions. This is because the cell walls of macrofungi are enriched with several functional groups that provide key aspects in the biosorption process. In this chapter, the biosorptive propensity of different mushrooms toward metal ions has been accented, and also insights into mechanisms of biosorption are discussed.