Exploiting Microalgae for efficient removal of heavy metals: An in-silico approach

Document Type : Review Paper

Authors

1 Department of Biotechnology, Sri Padmavati Mahila Visvavidyalayam (Women’s University), Tirupati, Andhra Pradesh, India

2 School of Engineering and Technology, Sri Padmavati Mahila Visvavidyalayam (Women’s University), Tirupati, Andhra Pradesh, India

3 Muga Eri Silkworm Seed Organization Central Silk Board, Guwahati, Assam 781022, India

4 School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, India

Abstract

In recent years, bioremediation has attracted a great deal of attention because of environmental pollutants and their implications for public health and environmental sustainability. In bioremediation, microalgae play a major role in environmental and wastewater treatment techniques. Among environmental contaminants, heavy metals (HMs) are significant pollutants due to their persistence in the environment and their potential to harm ecosystems and human health. Several conventional techniques are available for removing heavy metals, but they are expensive. Microalgae afford an environmentally friendly approach for heavy metal remediation. This review examines the major sources and health effects of heavy metals, including chromium (Cr), arsenic (As), zinc (Zn), cadmium (Cd), Iron (Fe), mercury (Hg), lead (Pb), and Copper (Cu), emphasizing microalgae as a potent tool for heavy metal decontamination. The primary analyses observed microalgal metallothioneins (MTs) and their potential to improve metal sequestration, supported by computational investigations of metal-MT interactions. The study revealed that metal ions with MT proteins binding energies of MT ranged between -16.67 to –3.24 kcal/mol for P. tenue and –5.90 to –3.21 kcal/mol for C. sorokiniana, –2.86 to –1.41 kcal/mol for S. platensis, indicating variable but significant affinity for different metal ions. These results suggest that microalgal MTs play an important role in heavy metal uptake and can be further enhanced using computational and biotechnological techniques. Based on the evidence reviewed, microalgae-based bioremediation systems with MT-enhanced strains are recommended as a potential and long-term solution for heavy-metal removal.

Graphical Abstract

Exploiting Microalgae for efficient removal of heavy metals: An in-silico approach

Keywords

Main Subjects


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