Time–Dependent Hydrolysis of Starch by Mutant B. subtilis EBUE 5–3 α–Amylase, Investigation of Its Effect on Starch Granules by SEM Microscopy

In this study, the hydrolysis products of soluble potato starch by α–amylase from mutant B. subtilis EBUE 5–3 were determined in time. The enzyme was observed as hydrolysis products from starch within the first 5 minutes as G2, G3 and G5 and a small amount of G4. G4 was detected between 15-45 minutes, while G5 was observed in small amounts in 15 minutes. G4 and G5 were not observed at other times. The amounts of G1, G2 and G3 increased with the increase of time. A small amount of G1 and a large amount of G2 and G3 were obtained as the final main products. The degradation capabilities of the enzyme on raw wheat, corn, rice and potato starch granules were investigated by scanning electron microscope. While deep holes were observed in wheat, corn and rice granules, a spongy structure was formed in rice and corn granules. It was observed that the surfaces of both were completely degraded. Only superficial disintegration was determined in potato granules. It was determined that the enzyme preferred rice, corn and wheat as the best starches in terms of substrate specificity, respectively.