Pale yellow or white lyophilized powder, soluble in water and dilute buffer solution, insoluble in ethanol, pI4.77, optimal pH 4.0-5.0. Stability: optimal temperature 50-55℃, inactivated at temperatures higher than 85℃; slightly acid-resistant, inactivated at pH less than 1.7; turns blue when exposed to iodine. Inhibitors: heavy metal ions (Cu2+, Ag+, H2+), urea, cyclohexyl straight-chain starch, methyl α-glucoside, sulfhydryl reagents (4-chloromercuric acid benzoic acid, iodoacetammonium). absorbance coefficient of a 1% aqueous solution at 280 nm is 12.3. enzyme reaction: starch (soluble) + nH2O ═ n maltose + dextrin.
β -Amylase is used to hydrolyze α bonds of α-linked polysaccharides, such as starch and glycogen. β -Amylase, has been used in various plant studies, such as carbon starvation studies in Populus tremuloides 1 . β -Amylase, from barley, has been used to study how pressure and temperature affect catalytic activity.
In starch processing, brewing, distilling, baking, animal feed, sewage treatment.
β-Amylase is a gel filtration molecular weight marker that can be used in gel filtration chromatography and protein chromatography. β-Amylase can be purified by affinity precipitation with alginate.
β-Amylases belongs to the class of amylolytic enzymes.
Flammability and Explosibility
Not classified
β-Amylase hydrolyzes the α-(1,4) glucan linkages in polysaccharides of three or more α-(1,4) linked D-glucose units. Natural substrates such as starch and glycogen are broken down into glucose and maltose. Pure, crystalline β-amylase preparation consists of four isoenzymes with different isoelectric points. The enzyme polymerizes very rapidly through the sulfhydryl groups in the absence of reducing agents. p-Chloromercuribenzoate inhibits the polymerization and the enzymatic activity. The reducing agents mercaptoethanol or dithiothreitol can completely restore the activity.
