author(s)
Nisha Kumari, Sushil, Babita Rani, Kamla Malik and Ram Avtar

abstract
Amylase is an extracellular enzyme, which is involved in the starch processing industries where it breaks starch into simple sugar constituents. Two major classes of amylases namely α-amylase and glucoamylase have been identified in microorganisms. In addition, β-amylase which is of plant origin has also been reported from few microbial strains. These amylases are usually extracellular and are widely distributed in bacteria, actinomycetes and fungi. Amylases are of ubiquitous occurrence and holding maximum market share of enzyme sales. Compared to plant and animal origins, microbial α-amylase is the most popular source of industrial α-amylase. Microbial sources of α-amylases are cost effective and appropriate for industrial demands. These microbial amylases are now available commercially and they have almost completely replaced acid hydrolysis of starch in starch processing industry because of number of advantages such as specificity of the reaction, stability of the generated products, lower energy requirements and elimination of neutralization steps. Amylase has wide application in starch processing, baking, brewing, sugar production, textile industries and in detergent manufacturing processes. Interestingly, the first enzyme produced industrially was an amylase. This review focuses on the production, purification, characterization and immobilization of microbial amylase.