refers to an enzyme capable of hydrolyzing starch, glycogen and O-glucose linkages in related polysaccharides. Generally, it acts on α-1,4-glucan such as soluble starch, amylose, and glycoside, and an enzyme that hydrolyzes α-1,4-glycosidic bond. Amylase is a general term for enzymes that hydrolyze starch and glycogen. Catalytic hydrolysis of starch slurry on fabrics is usually carried out by amylase.
Due to the high efficiency and specificity of amylase, the desizing rate of enzyme desizing is high, and desizing is fast with less pollution, the product is softer than products produced by acid and alkali method without fiber being damaged. There are many kinds of amylases. Depending on the different fabric, different equipment combination and different process flow, the desizing methods used at present include dipping method, stacking method, volume dyeing method, continuous washing, etc., due to the smallmachinery effect of amylase desizin, and the amount of water used is small, the desizing effect can be achieved under low temperature conditions with distinctive environmental protection feature.
, also known as alpha glucoamylase
, is a customary name known as alpha-1,4-Glucan glucohydrolace. This product is used in alcohol, starch sugar, monosodium glutamate, antibiotics, citric acid, beer and other industries as well as white wine, yellow wine, Qu wine and other brewing industries, the quality of this product is stable, it is easy to use, and conducive to continuous saccharification, improve product quality and reduce costs. Glycosylase generally has no toxic side effects.
Amylase generally acts on α-1,4-glucan such as soluble starch, amylose, and glycoside, and an enzyme that hydrolyzes α-1,4-glycosidic bond. According to the mode of action, it can be divided into α-amylase (EC 220.127.116.11.) and β-amylase (EC 18.104.22.168.).
(1) Alpha-amylase is widely distributed in animals (saliva, pancreas, etc.), plants (malt, hawthorn), and microorganisms. Microbial enzymes are almost all secreted. This enzyme uses Ca2+ as an essential factor and acts as a stabilizing factor, acting on both amylose and amylopectin, and cleavage of the α-1,4-chain without distinction. Therefore, it is characterized by a sharp drop in the viscosity of the substrate solution and the disappearance of the iodine reaction, and the final product is mainly maltose in the decomposition of amylose, in addition to maltotriose and a small amount of glucose. On the other hand, in the decomposition of amylopectin, in addition to maltose and glucose, an α-limit dextrin having a branching moiety having an α-1,6-bond is formed. The general decomposition limit is 35-50% based on glucose, but in the bacterial amylase, there are also up to 70% decomposition limit (final release of glucose);
(2) The difference of β-amylase and α-amylase(Alpha Amylase
) is that the α-1,4-glucan chain is cleaved in units of maltose from the non-reducing end, which is mainly found in higher plants (barley, wheat, sweet potatoes, soybeans, etc.), but also reported in bacteria, milk, mold. Substrates that are not branched like amylose can be completely decomposed to give maltose and a small amount of glucose. When it acts on amylopectin or dextran, the reaction before the cleavage to the α-1,6-bond is stopped, so that a limit dextrin having a relatively large molecular weight is formed. From the above-mentioned modes of action of α-amylase and β-amylase, the names of α-1,4-glucan 4-glucanohydrolase and α-1, 4-glucan-maltose hydrolase (α-1,4-glucan maltohydrolase) etc. were proposed respectively and used.