Abstract
Action of bacterial β-amylase of three strains isolated from soils on raw starches were studied in comparison with β-amylase of soy-bean. Three bacterial β-amylases have been strongly adsorbed on raw starch granules and digest it. On the other hand, soy-bean β-amylase is adsorbed on raw starch imperceptibly, but digests it a little.
The β-amylase of a strain Bacillus sp. No. 2718 has a strong activity to digest raw starch.
The effects of temperature on raw starches digestion of corn, wheat by No. 2718 β-amylase and soy-bean enzyme were as follows; 1) The bacterial β-amylase easily digested every raw starch below its gelatinization temperature but soy-bean β-amylase digested it a little. 2) Raw starch digestion by No. 2718 β-amylase is accelerated by heating.
Starch granules digested by No. 2718 β-amylase and soy-bean enzyme were observed by scanning electron microscopy.
