Halophiles as a source of polyextremophilic α-amylase for industrial applications

Halophiles are perceived as an excellent source of novel enzymes possessing inherent ability to function under saline and hypersaline environment conditions. The article covers and puts in perspective the structural and biocatalytic features of α-amylases from halophilic sources. The choice of α-amylase as the target enzyme is based on the fact that this is among the largest selling enzymes. Oligosaccharide synthesis is favored in presence of organic solvents and at high temperature. For this reason, the demand for α-amylases that are functional at high temperature and salt as well as stable towards organic solvents, is on the rise in recent years. Halophilic α-amylases are deemed to possess all the above characteristics. They are generally salt stable. In terms of water activity, saline environments are similar to non-aqueous systems. Therefore halophilic α-amylases also exhibit stability in organic solvents. In this context, the review encompasses α-amylase producing predominant halophilic microorganisms from saline habitats; strategies adopted for purification of halophilic α-amylase; their salient structural features and unique functional characteristics. Halophilic α-amylase applications and future aspects in research are also analyzed.