Isolation of Amylase Inhibitor-producing Microorganism

An amylase inhibitor-producing microorganism was identified as a subspecies of Strepto- myces diastaticus from morphological and physiological studies and was named Streptomyces diastaticus subsp. amylostaticus No. 2476.

When this strain was aerobically cultured in a shaking flask containing 100 ml of medium consisting of 4% corn starch, 2% soy bean flake extract, 0.3 % NaCl, 0.1 % K₂HPO₄, 0.05% MgSO₄·7H₂O, 0.001% FeS0₄ · 7H₂O, 0.0001% CuSO₄-5H₂O, 0.0001% ZnSO₄·7H₂O, and 0.0001% MnS0₄ nH₂O (pH 7.0) at 30°C, the highest inhibitory activity was obtained after 70 ~ 80 hr of cultivation.

This amylase inhibitor (S-AI) had inhibitory activity on α-amylases and glucoamylase, but not on β-amylases and pullulanase.