Extremophiles are organisms that can survive in harsh environmental
conditions such as varying ranges of temperature, pH, high levels of salinity, extreme
pressure and high doses of radiation. They are distributed throughout the Earth’s
surface and water bodies. They are classified on the basis of their habitats and extreme
conditions they inhabit, like oligotrophs, thermophiles, psychrophiles, halophiles,
acidophiles, alkaliphiles, piezophiles and radiophiles. Extremophiles have a huge
impact on human life. Enzymes obtained from them are nowadays used in industrial
microbiology, agriculture, pharmaceuticals and medical diagnostics, bioremediation,
and in many more fields. With enormous commercial benefits and advanced scientific
techniques, researchers are investigating extremophiles for a better understanding of
their metabolism, and survival strategies for newer applications. This chapter focuses
on applications of different types of extremophiles in industry, scientific research,
medical science, and other fields.
Keywords: Acidophiles, Alkaliphiles, Bacteriorhodopsin, Cold-active enzymes, Compatible solutes, Extremophiles, Extremozymes, Halophiles, Heavy-metal resistance, Industrial applications, Mycosporine-like amino acids, Oligotrophs, PGPR, Piezophiles, Polyextermophile, Poly-β hydroxyl alkanoates, Psychrophiles, Radiophiles, Thermophiles.