Reduction of Heavy Metal Pollution Using Brown Algae: A Review

Industrial heavy metal pollution and other effluents from chemical industries are of great concern for the ecosystem. Due to this, toxic waste water is released into the environment causing severe heavy metal pollution and also affects our health. The physicochemical methods are expensive and these results in the incomplete removal of metal ions. As a result, other alternative methods such as algae bioremediation are taken into account which have the ability to absorb metal ions and this very idea can be used in the treatment of wastewater. They absorb metal ions on the cell surface and in the intracellular ligands. Before releasing algae into waste water, they are treated with pretreatment. Various pretreatment improves the enhancement of metal sorption in algae. The most suitable and economic method for cultivating algae biomass is the calcium chloride pretreatment. When considering algae, there are various strains and hence, selection of strain is highly important. This happens by the understanding of bio sorption mechanisms, increasing the number of surface groups with genetic manipulation of algae and creating them for economic feasibility. In brown algae, the order Laminariales and Fucale species are considered as efficient groups of algae while bio-sorption is considered, because their cell wall is very rich in extracellular polymers and polysaccharides. Considering these parameters in the significant development of low-cost algae cultivation and an eco-friendly solution for the pollution caused by chemical industries, this work concentrates on the bioremediation process for the reduction of heavy metal pollution.