Halophiles and Halotolerants: From Industry to Astrobiology.

Halophilic and halotolerant microorganisms, as members of the extremophile group, hold significant potential for both industrial applications and astrobiological research. Conventional microorganisms used in wastewater treatment and bioremediation often cannot withstand the high salinity present in industrial effluents and certain contaminated environments. Similarly, planetary environments such as those on Mars, Europa, and Enceladus are often considered inhospitable due to extreme salinity, temperatures, and radiation levels. However, halophiles possess adaptive mechanisms that allow them to thrive under such harsh conditions, including high salt concentrations, extreme pH, temperature, and ultraviolet radiation. This review explores the primary industrial applications of halophilic and halotolerant microorganisms-particularly their roles and the use of their enzymes in saline wastewater treatment and bioremediation. It also examines the habitability of other planetary bodies and highlights how the unique adaptations of halophiles make them valuable model organisms for astrobiological studies. A deeper understanding of these mechanisms is essential not only for expanding their industrial use but also for shedding light on their evolutionary trajectories on Earth and their potential to survive and evolve beyond our planet. Importantly, this review emphasizes the need for an integrated approach that avoids dissociating biotechnology and astrobiology, recognizing the mutual benefits that arise from collaboration between these fields.