Enzymes which cleave glucosidic linkages in e.g. STARCH or GLYCOGEN . α- Amylases ((1 → 4)-α- D -glucan 4-glucanhydrolases, EC 3.2.1.1) are endoenzymes which have little action on terminal (1 → 4)-α-bonds or on bonds adjacent to (1 → 6)-α branch points. They act on amylopectin and glycogen to form glucose, maltose and branched α-limit DEXTRINS , and on amylose to form first maltose and maltotriose, then slowly on maltotriose to form maltose and glucose. α-Amylases are common among microorganisms. They are obtained commercially mainly from Bacillus spp (see also IMMOBILIZATION (sense 1)) and are used e.g. for processing starch to form glucose syrups: insoluble starch granules are dispersed in water by heating, and the starch is partially hydrolysed with thermostable α-amylases from B. amyloliquefaciens and/or B. licheniformis . Further hydrolysis is achieved using e.g. γ-amylases (see below). β- Amylases ((1 → 4)-α- D -glucan maltohydrolases, EC 3.2.1.2) are exoenzymes which cleave…