Classification and Function of Amylase

Amylase (AMS), also known as 1,4-α-D-glucanohydrolase, is a general term for enzymes that hydrolyze starch and glycogen. The main function of amylase is to break down starch to produce simple sugars such as fructose, maltose, glucose and dextrin. Amylases are also used in food and beverage processing and other industries.

Classification of amylases
1. Alpha-amylase
Alpha-amylase is mainly distributed in animals (saliva, pancreas, etc.), plants (malt, arugula) and microorganisms. This enzyme takes Ca2+ as an essential factor, and also uses it as a stabilizing factor and an activating factor, and some amylases are non-Ca2+ dependent. Amylase acts on both amylose and amylopectin, and randomly cuts off the α-1,4-chain inside the sugar chain without distinction.

2. Beta-amylase
It differs from α-amylase in that the α-1,4-glucan chain is successively cleaved in units of maltose from the non-reducing end. Beta-amylase is mainly found in higher plants (barley, wheat, sweet potato, soybean, etc.), but it has also been reported to exist in bacteria, milk, and molds. For unbranched substrates like amylose, maltose and a small amount of glucose can be completely decomposed.

3. γ-Amylase
γ-amylase (γ-amylase) is an exonuclease that cleaves α(1→4) and α(1→6) glycosidic bonds from the non-reducing end of starch molecules, and cleaves glucose residues one by one. Similar to β-amylase, the free hemiacetal hydroxyl group produced by hydrolysis undergoes translocation to release β-glucose.

Amylase is produced by the endocrine glands of humans and animals and is necessary because starch molecules are often too large to be used in their intact form. The human body obtains energy from simple sugars produced by amylase. Without amylase to break down starch in this way, most foods would be inedible to humans.

Amylases are thought to be involved in evolution. Some scientists believe that amylase levels in the body rise over time in response to the need to adjust dietary intake for survival. This concept has been supported by genetic studies. Amylase allows people to eat other foods in addition to protein and fruit, and more food choices could theoretically reduce the risk of death.

In the oral cavity, the function of amylase is to act as a catalyst for digestion. The tongue can detect sugar produced by amylase, which is why starch tastes slightly sweet when people chew it. The pancreas also produces amylase, which travels through the pancreatic and common bile ducts into the duodenum. There, the main function of amylase is to break down complex carbohydrates. In addition, a small amount of amylase is also present in the fallopian tubes.

Amylase can be measured in body fluids, such as urine and blood, and can provide clues to certain medical conditions. For example, the pancreas produces amylase, so abnormal amylase may be a sign of pancreatic inflammation.

In food preparation, amylase functions the same as in the body. The breakdown of starch allows the production of items such as glucose syrup, which is used as an additive in various products such as ketchup. Brewers and chefs use amylase to produce products such as beer, bread and cakes.

Another area of amylase use is cleaning. Amylase's ability to break down starch makes it useful for removing starch-based spots from clothing or other items. In aquaculture, amylase is added to animal feed to help animals get more sugar for energy from starch-based feeds, helping farmers reduce costs.