Management of heavy metal pollution by using yeast biomass

Abstract

In recent years, the management of heavy metal pollution has become a major issue. Toxic heavy metals pose a serious threat to the environment and living forms. A number of conventional methods have been developed for the recovery of toxic heavy metals. On account of some disadvantages associated with these methods, biosorption onto microbial biomass has become an attractive alternative. Among microorganisms, yeasts have received considerable attention on account of yeast biomass being easily obtainable from inexpensive media. This is also abundantly generated as a by-product from the fermentation industry. Based on the published literature, the principles, methodologies and techniques involved in the management of heavy metals by yeast systems are summarized in this chapter. Adsorption capacities of different yeasts for a variety of heavy metals have been compared. Dependence of yeast biomass metal-binding capacities on parameters such as pH, temperature, contact time, competitive metal ions, agitation, initial metal ions and biomass concentrations have been explained. Isotherms, equilibrium models and kinetics have also been extensively discussed. Mechanisms involved in the biosorption by yeasts and the future prospects of this biotechnologically relevant topic have been highlighted.