Amylase
Amylase is an important enzyme produced mainly from microbial sources and is used in many industries. They are broadly classified into α, β, and γ subtypes. α- Amylase and β- Amylase are widely studied out of which α Amylase is fast acting. Substrates for this enzyme are available from cheap plant substrates hence the enzyme is cost effective and efficient. However, amylases produced by microbes are most preferred due to the high yield and availability and since they can be easily manipulated. Amylases are one of the most important industrial enzymes that have a wide variety of applications ranging from conversion of starch to sugar syrups, to the production of cyclodextrins for the pharmaceutical industry. These enzymes account for about 30 % of the world’s enzyme production. The α Amylase family can be roughly divided into two groups: the starch hydrolysing enzymes and the starch modifying or the transglycosylating enzymes. The enzymatic hydrolysis is preferred to acid hydrolysis in starch processing industry due to a number of advantages such as specificity of the reaction, stability of the generated products, lower energy requirements and elimination of neutralizing steps.
Commercial Applications:
It used in foods, detergents, pharmaceuticals, and the paper and textile industries
Food industry: It is used in the production of corn syrups, maltose syrups, glucose syrups, juices and alcohol fermentation, baking and food additive.
Brewery: it is used in beer and liquor brewing from sugars (based on starch). Here, yeast is used to ingest sugars, and alcohol is produced. Fermentation is suitable for microbial amylase production under moisture and proper growth conditions. Two kinds of fermentation processes have been followed: submerged fermentation and solid-state fermentation. The former is the one traditionally used and the latter has been more recently developed. In traditional beer brewing, malted barley is mashed and its starch is hydrolyzed into sugars by amylase at an appropriate temperature. By varying the temperatures and conditions for α- or β-amylase activities, the unfermentable and fermentable sugars are determined. With these changes, the alcohol content and flavor and mouthfeel of the end product can be varied.
Pharmaceuticals: For this industry, the crude version is not used, rather purified enzyme is required. This can be accomplished by ion-exchange chromatography, hydrophobic interaction chromatography, gel filtration, immunoprecipitation, polyethylene glycol/Sepharose gel separation, and aqueous two-phase and gradient systems where the size and charge of the amylase determine the method chosen.
Future Perspectives:
Among the different enzymes, amylase possesses the highest potential for use in different industrial and medicinal purposes. The involvement of modern technologies, such as white biotechnology, pinch technology, and green technology, will hasten its industrial production on a large scale. This will be further facilitated by the implementation of established fermentation technologies with appropriate microbial species (bacteria or fungi) and complementation of other biotechnological aspects. The technologies of high-throughput screening and processing with efficient microbial species, along with the ultimate coupling of genetic engineering of amylase-producing strains, will all help in enhancing amylase production for industrial and medicinal applications.