Amylase is a general term for enzymes that hydrolyze starch and glycogen, usually through amylase catalyzed hydrolysis of starch slurry on fabrics. Due to the high efficiency and specificity of amylase, the enzyme desizing has a high desizing rate, fast desizing, less contamination, and the product is softer than the acid method and the alkaline method, and it does not damage the fibers. There are many kinds of amylase, according to the different fabrics, different equipment combinations, different processes, the desizing methods used at present are impregnation method, stacking method, roll dyeing method, continuous washing, etc. Due to the small mechanical effect of amylase desizing, the amount of water is small, and the desizing effect can be achieved at low temperature, with distinctive characteristics of environmental protection. Amylase,Isoamylase,Main uses,Clinical significance,Increase,Decrease,Elevation of serum amylase,Amylase isoenzymes,Related information, Introduction Amylase amylase,Amy,AMS is generally used to hydrolyze the alpha-1,4-glucan in soluble starch, straight-chain amylopectin, glycogen, etc. The enzyme has been shown to hydrolyze alpha-1,4-glucoside bonds in a wide range of amyloidogenic environments. -1,4-glycosidic bond enzymes. According to the enzyme hydrolysis product isomerization type can be divided into α-amylase (EC3.2.1.1.) and β-amylase (EC3.2.1.2.). α-Amylases are widely distributed in animals (saliva, pancreas, etc.), plants (malt, sorrel) and microorganisms. Microbial enzymes are almost always secreted. The enzyme is Ca2+ essential and acts as a stabilizing and activating factor, while some amylases are non-Ca2+ dependent. Amylases act on both straight-chain and branched-chain starches, indiscriminately and randomly severing the α-1,4-chain within the sugar chain. Therefore, its characteristic is to cause a sharp drop in the viscosity of the substrate solution and the disappearance of the iodine reaction, the end product in the decomposition of straight-chain starch is mainly glucose, in addition, there are a small amount of maltotriose and maltose, in which the end product of the hydrolysis of starch by the fungal a-amylase is mainly maltose-based and does not contain large molecules of the limit of the dextrin, in the bakery and the maltose manufacturing industry has a wide range of applications. On the other hand, in the decomposition of branched-chain starch, in addition to maltose, glucose and maltotriose, α-limit dextrin (also known as α-dextrin) with α-1,6-bonds is also generated in the branch part. The general breakdown limit is 35-50% in terms of glucose, but in bacterial amylases, up to 70% breakdown limit is observed (eventually freeing glucose); β-amylase is widely distributed Differs from α-amylase in that it cuts off the α-1,4-glucan chain from the non-reducing end, one by one, using maltose as a unit. Mainly found in higher plants (barley, wheat, sweet potatoes, soybeans, etc.), but also reported in bacteria, cow's milk, and molds. Completely breaks down unbranched substrates like straight-chain starches to give maltose and small amounts of glucose. When acting on branched-chain starches or glucans, the reaction in front of the cut to the α-1,6-bond stops, so that the ultimate dextrin with a relatively high molecular weight is produced. From the above mentioned modes of action of α-amylase and β-amylase, α-1,4-glucan 4-glucanohydrolase (α-1,4-glucan 4-glucanohydrolase) and α-1,4- glucan-maltose hydrolase (α-1,4-glucan maltohydrolase) are used, among other names. γ-amylase Glucoamylase, glycolytic enzyme, No. E.C.3.2.1.3 γ-amylase (γ-amylase) is an exonuclease that cuts the α(1→4) linkage glycosidic bond and the α(1→6) linkage glycosidic bond sequentially from the non-reducing end of the starch molecule, cutting down the glucose residues one at a time, and in a similar fashion to β-amylase, the hydrolysis produces free hemiacetal hydroxyls which undergo transversion, releasing β-glucose The free hemiacetal hydroxyl group produced by hydrolysis is translocated to release β-glucose. Whether it acts on straight-chain starch or branched-chain starch, the end product is glucose. Isoamylases Starch-1,6-glucosidase, No. E.C.3.2.1.33 Animals, plants, and microorganisms all produce isoamylases. The sources are different and have different names, e.g., debranching enzyme, Q enzyme, R enzyme, purulanase, thioglycosidase, etc. Hydrolyzes the alpha-1,6-glycosidic bond of branched-chain starch or glycogen to produce straight-chain starch (dextrin) of varying lengths. Mainly produced by microbial fermentation, strains of yeast, bacteria, actinomycetes. Main uses Used as starch decomposition and improve filtration speed in fruit juice processing, as well as vegetable processing, syrup manufacturing, glucose and other processing and manufacturing. Clinical significance Increased in pancreatic duct obstruction caused by pancreatic tumors, pancreatic abscess, pancreatic injury, intestinal obstruction, gastric ulcer perforation, mumps, peritonitis, biliary tract disease, acute appendicitis, cholecystitis, peptic ulcer perforation, renal failure or renal insufficiency, tubulitis, traumatic shock, major postoperative period, pneumonia, lung cancer, acute alcoholism, morphine injection, and oral contraceptives , sulfonamides, thiazide diuretics, opiates (codeine, morphine). Narcotic painkillers, etc. Decreased See cirrhosis, hepatitis, hepatocellular carcinoma, acute or chronic cholecystitis, etc. Pancreatic amylase is excreted from the pancreas into the digestive tract in an active state, and is the most important enzyme that hydrolyzes carbohydrates. It belongs to the alpha-amylase enzyme as does amylase secreted by the salivary glands, acts on the alpha-1,4 glycosidic bond, and has no effect on the alpha-1,6 glycosidic bond on the branches, and is therefore also known as amyloid endonuclease. The optimal pH for its action is 6.9, and it can pass through the glomerular filtration, and it is the only plasma enzyme that can be found in the urine at normal times. It is the only plasma enzyme that appears in urine at normal times. Amylase activity is found in extracts of other human tissues such as ovaries, fallopian tubes, lungs, testes, ***, mammary glands, etc.; amylase is also found in blood, urine, and emulsions. Blood amylase in the main from the pancreas, salivary glands, urine amylase from the blood. When serum amylase isoenzymes were measured, two major isozyme bands and several minor bands were found. One of the two major bands was electrophoresed in the same position as the purified material or secretion from the pancreas, hence the name P-isozyme; the other was electrophoresed in the same position as the purified material or saliva from the salivary gland, hence the name S-isozyme. Determination of amylase isoenzymes helps in the differential diagnosis of pancreatic diseases. Reference values: Limiting substrate method: Serum amylase 220U/L(37℃) Urine amylase 1200U/L(37℃) P-isoenzyme Serum 115U/L Urine 800U/L Serum amylase of newborns is about 18% of that of adults, mainly S-type, and reaches the level of human at the age of 5 years old; within one year of age, no measurement of serum P-type amylase, and then slowly rise, and reach the level of human at the age of 10 to 15 years old. The serum P-type amylase is not detected in the first year of life, and then rises slowly to reach the human level at the age of 10-15 years. Serum amylase and urine amylase are the most commonly used laboratory diagnostic methods for pancreatic diseases. When pancreatic diseases or pancreatic exocrine dysfunction are present, their activity can be elevated or lowered, which can help in the diagnosis of pancreatic diseases. Urine amylase levels fluctuate greatly, so serum amylase is preferred, or both. Changes in amylase activity can also be seen in some non-pancreatic disorders, so the measurement of amylase isoenzymes is of differential diagnostic significance when necessary. Elevated serum amylase is most commonly seen in acute pancreatitis and is one of the most important diagnostic indicators of acute pancreatitis. The activity starts to increase 6-12h after the onset of the disease, peaks at 24h, decreases at 48h, and returns to normal after 3-5 days. Although the degree of elevated amylase activity is not necessarily related to the degree of pancreatic injury, the greater the degree of elevation, the greater the likelihood of acute pancreatitis, therefore, although amylase is still used as the first choice of diagnostic indicators of acute pancreatitis, its specificity and sensitivity are not high enough. When acute pancreatitis is suspected, the patient's serum and urinary amylase activity should be observed continuously and dynamically, and can be combined with the clinical situation and other tests, such as pancreatic lipase, pancreatic protease and other measurements***similar analysis to make a diagnosis. Amylase assay is also valuable in monitoring the complications of acute pancreatitis, such as pancreatic pseudocysts and pancreatic abscesses, in which blood amylase activity is continuously elevated. Severe acute pancreatitis can cause pleural effusion or/and abdominal effusion, and the amylase activity in the effusion can be even more than 100 times higher than the serum amylase activity. The diagnosis of acute pancreatitis is difficult because other acute abdominal conditions can also cause elevated amylase activity. Therefore, when acute pancreatitis is suspected, in addition to continuous monitoring of amylase, it should be combined with the clinical situation and other tests, such as pancreatic lipase, pancreatic protease and other measurements **** with the analysis, to make a diagnosis. Chronic pancreatitis amylase activity can be mildly increased or decreased, but without great diagnostic significance. Early pancreatic cancer amylase activity is seen to be elevated. Moderate or mild elevation of amylase activity can also be seen in some non-pancreatic diseases, such as mumps, acute abdominal diseases (peptic ulcer perforation, after upper abdominal surgery, mechanical intestinal obstruction, mesenteric vascular lesions, biliary obstruction and acute cholecystitis, etc.), the use of analgesic agents, alcoholism, renal dysfunction and mega-amylasemia, etc., which should be noted. Blood amylase is filtered by the glomeruli, so any elevation of serum amylase from any cause will result in increased urinary amylase excretion, especially in acute pancreatitis. Amylase isoenzymes Serum amylase originates from the salivary glands and many other tissues in addition to the pancreas, so the measurement of isoenzymes can help in the differential diagnosis of the disease when amylase activity is elevated. elevated or lowered P-isoenzymes indicate that pancreatic disorders may be present; S-isoenzymes changes may originate in the salivary glands or other tissues. When serum amylase activity is elevated and the diagnosis is not clear, further isoenzymes should be measured to aid in the differential diagnosis. There are a number of methods to measure isoenzymes, agarose and vinyl fiber membrane electrophoresis being among the more commonly used. The results of amylase are greatly affected by the method, and the reference value of different methods is also different, and the methods used in the clinic are also more, so it is necessary to understand the measurement method used and its reference value, in order to make a correct diagnosis. Related information Some people in order to moisturize the lips, like to use the tongue to lick, in fact, this is a bad habit, because licking the lips can only bring a short period of wet, when these lips when the water evaporation will take away more water inside the lips, so that your lips into the "dry - lick - more dry! -Licking again" in the vicious circle, the result is the more you lick the more pain, the more you lick the more cracked. At the same time saliva contains amylase and other substances, the wind blew, water evaporation, take away the heat, so that the lip temperature is lower, amylase on the lips, will cause the deep connective tissue contraction, the lip mucous membrane wrinkled, and thus dry more. In severe cases, it can also become infected and swollen, causing pain. Amylase causes dry lips