α~Amylase lba3000l was purified from Bacillus subtilis by deep culture and extraction. This product is a liquid enzyme preparation. It is a kind of endoamylase, which can hydrolyze starch, glycogen and their degradation products randomly α～ 1.4 glycosidic bond makes the viscosity of colloidal starch solution decrease rapidly, resulting in soluble dextrin and maltose. Excessive hydrolysis can produce a small amount of glucose and maltose. This product is also widely used in starch, sugar, alcohol, Baijiu, beer, MSG, soy sauce, pharmaceutical, textile, printing and dyeing desizing.