Metal biorecovery and bioremediation: Whether or not thermophilic are better than mesophilic microorganisms

• Published in: Bioresource technology Vol. 279; pp. 317 - 326
• Main Authors: Castro, C., Urbieta, M.S., Plaza Cazón, J., Donati, E.R.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.05.2019
• Subjects: Archaea; Biodegradation, Environmental; Biorecovery; Bioremediation; Biotechnology - methods; Metals; Metals - metabolism; Thermophiles; Tolerance; Tolerance; Bioremediation; Biorecovery; Metals; Thermophiles
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2019.02.028

•Thermophiles and mesophiles share similar metal-resistance strategies.•Mesophiles seem to be more tolerant to metals than thermophiles.•Thermophiles are successfully used in metal biorecovery and/or bioremediation processes.•High temperature helps to attack recalcitrant compounds in bioprocesses.•Ubiquitous presence of thermophiles favors their use in in-situ bioremediation processes. Metal mobilization and immobilization catalyzed by microbial action are key processes in environmental biotechnology. Metal mobilization from ores, mining wastes, or solid residues can be used for recovering metals and/or remediating polluted environments; furthermore, immobilization reduces the migration of metals; cleans up effluents plus ground- and surface water; and, moreover, can help to concentrate and recover metals. Usually these processes provide certain advantages over traditional technologies such as more efficient economical and environmentally sustainable results. Since elevated temperatures typically increase chemical kinetics, it could be expected that bioprocesses should also be enhanced by replacing mesophiles with thermophiles or hyperthermophiles. Nevertheless, other issues like process stability, flexibility, and thermophile-versus-mesophile resistance to acidity and/or metal toxicity should be carefully considered. This review critically analyzes and compares thermophilic and mesophilic microbial performances in recent and selected representative examples of metal bioremediation and biorecovery.