Amyloglucosidase (EC 3.2.1.3) is an important industrial enzyme that is used by the manufacturers of high fructose corn syrup (HFCS). More than half of all commercial baked goods and practically all soft drink bottlers use this syrup instead of sugar because HFCS is both sweeter and cheaper. Amyloglucosidase catalyzes the breakdown of malto-oligosaccharides to glucose.
Amylase is a digestive enzyme classified as a saccharidase (an enzyme that cleaves polysaccharides). It is mainly a constituent of pancreatic juice and saliva, needed for the breakdown of long-chain carbohydrates (such as starch) into smaller units.
Amylase is a digestive enzyme made primarily by the pancreas and salivary glands. Enzymes are substances made and used by the body to trigger specific chemical reactions. The primary function of the enzyme amylase is to break down starches in food so that they can be used by the body. Amylase is also synthesised in the fruit of plants during ripening, causing them to become sweeter.
Amylases are enzymes that catalyze the hydrolysis of alpha-1, 4-glycosidic linkages of polysaccharides to yield dextrins, oligosaccharides, maltose and D-glucose. Amylases are derived from animal, fungal and plant sources. Pancreatin and pancrelipase contain amylase derived from the pancreas of animals, usually porcine pancreas.
Amylase is also derived from barley malt and the fungus Aspergillus oryzae. There are a few different amylases. These enzymes are classified according to the manner in which the glysosidic bond is attacked. Alpha-amylases hydrolyze alpha-1, 4-glycosidic linkages, randomly yielding dextrins, oligosaccharides and monosaccharides. Alpha-amylases are endo- amylases. Exoamylases hydrolyze the alpha-1, 4-glycosidic linkage only from the non-reducing outer polysaccharide chain ends. Exoamylases include beta-amylases and amyloglucosidases (gamma-amylases, amyloglucosidases). Beta-amylases yield beta-limit dextrins and maltose. Gamma-amylases yield glucose. Amylases are used as digestants.
Amylase is a calcium dependent enzyme which hydrolyzes complex carbohydrates at alpha 1,4-linkages to form maltose and glucose. Amylase is filtered by renal tubules and resorbed (inactivated) by tubular epithelium. Active enzyme does not appear in urine. Small amounts of amylase are taken up by Kupffer cells in the liver. In healthy dogs, 14% of amylase is bound to globulins. Because of this polymerization, canine amylase has variable (high) molecular weights and is not normally filtered by the kidney. In dogs with renal disease, this polymerized (macroamylase) amylase is found in higher concentration (from 5-62% of total amylase activity) and contributes to the hyperamylasemia seen in these disorders. There are 4 different isoenzymes of amylase in the dog: isoenzyme 3 is found in the pancreas (>50%), whereas isoenzyme 4 is found in all tissues. a-Amylase catalyzes the hydrolysis of internal (endoglycosidase) a-1,4-glucan links in polysaccharides containing 3 or more a-1,4-linked D-glucose units (amylose and amylopectin) yielding a mixture of maltose and glucose. Both of these monosaccharides can then be converted to about 30 ATP units of energy by encountering the glycolysis mechanism and the citric acid cycle. Both amylose and amylopectin are examples of polysaccharides, that is, polymers made of many sugar units. Both are composed entirely of glucose monomers. Amylose is a straight chain polymer of glucose units bonded by a-1,4 glycosidic linkages.
This means that neighboring glucose units are joined from the C1 carbon of one to the C4 carbon of the other, the bond having an orientation referred to as alpha. Amylopectin is a branched chain molecule. The glucose units in amylopectin are bonded in the same manner as in amylose, except for the branch points where the chains are joined by a-1,6 glycosidic linkages. Amylose composes from 20 to 30% of starch. Amylopectin comprises the remaining 70 to 80%, and because of its branching, is less soluble and more viscous than amylose.
Alpha-Amylase (1,4-a-D-glucan glucanohydrolase) in animals are monomeric, calcium-binding proteins that are present in both salivary and pancreatic secretions. In the gastrointestinal tract, it is a digestive enzyme that is secreted into the Duodenum where it starts to degrade (hydrolyze) the a-1,4 glucosidic linkages of starch to maltose and maltotriose. a-Amylases are used to hydrolyze glycogen, the reserve carbohydrates in animals, when the blood glucose levels are low. Salivary amylase, a major component of human salivary secretions, possesses multiple functions in the oral cavity. It is the only enzyme in the saliva capable of degrading oligosaccharides, which are used by the oral microflora for nutritional purposes. The structural neighbor, b-amylase, breaks down starch during the germination of seeds (rich in starch) into sugars. These sugars constitute the chief energy source in the early development of the plant. b-Amylase is able to break down the a-1,4 linkages of starch polymers in plants and seeds.
DESCRIPTION
Amyloglucosidase is an enzyme preparation which decomposes starch into glucose by tearing-off glucose units from the non-reduced end of the polysaccharide chain.It is derived by submerged fermentation of a specially selected producer strain of Asp.
PHYSICAL PROPERTIES
External appearance - Powder and liquid
Colour - Brown
Dry substance - Over 35%
Solubility - Water-soluble enzyme component
Enzyme Properties:
Optimum of pH of action - 4.50
Optimum temperature of action - 55-60˚ C
pH stability - 100% of the activity is preserved at pH 0 between 3.5 and 5.5, at temperature of 30 C, during 30 and 60 minutes
Temperature stability - more than 100% of activity is 0 preserved at temperature of 50 C during 60 minutes.
Application:
For saccharification of liquid starch in the preparation of amylaceous hydrolysates and of crystal glucose, in the brewing of beer with low dextrine content, in the production of bread and juices. |
