A delve into the exploration of potential bacterial extremophiles used for metal recovery

Deshpande, A.S.; Kumari, R.; Prem Rajan, A.

doi:10.22034/GJESM.2018.03.010

Document Type : REVIEW PAPER

Authors

¹ Department of Biotechnology, School of Biosciences and Technology, VIT, Vellore-632014, Tamil Nadu, India

² Department of Biomedical Sciences, School of Biosciences and Technology, VIT, Vellore-632014, Tamil Nadu, India

³ Department of Biomedical Sciences, School of Biosciences and Technology, CO2 and Green Technology Centre, VIT, Vellore-632014, Tamil Nadu, India

https://doi.org/10.22034/GJESM.2018.03.010

Abstract

A multitude of microbes are involved in the solubilisation of minerals and metals as this approach offers numerous advantages over traditional methods. This strategy is preferred as it is eco-friendly and economical, thus overcoming the drawbacks of the traditional approach of pyrometallurgy. Many different types of bacteria are employed in the process of Bioleaching, which are collectively grouped under chemolithotrophs, as they derive their energy from inorganic compounds. Bioleaching is the mobilization of metal cations from insoluble ores by microorganisms. All chemolithotropic bacteria are extremophiles since they have the ability to survive in extreme conditions. They carry out the process of Bioleaching through three mechanisms: Indirect, contact/ direct and cooperative bioleaching. This review gives a sneak peek into the different strains of chemolithotrophs which are used in bioleaching, and some recent work in the field. It also gives an insight into the general process and mechanism of Bioleaching, the study of which will pave way for developing better and efficient industrial bioleaching operations.

Graphical Abstract

Highlights

Elucidation of chemolithotrophs and Bioleaching revealed that many different chemolithotrophs play an active role in the process of bioleaching of various metals
Recent breakthroughs on various extremophiles used for bioleaching prove its enormous potential for future research in this field
The most common and widely used organisms for bioleaching belong to Acidithiobacillusand Leptospirillum genus and they are explored in this review
Three different mechanisms of bioleaching exist currently- direct, indirect and cooperative bioleaching; studying the mechanisms is required to develop better commercial bioleaching processes.

Keywords

Main Subjects

Environmental microbiology

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Letters to Editor

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