Achroic point

The ratio of dextrinogenic to saccharogenic activities for pancreatic amylase, measured with Lintner s soluble potato starch under comparable conditions at 40°, is approximately 2 to 45,57 The achroic point is reached in the hydrolysis of potato starch by highly purified pancreatic amylase when approximately 20% of the glucose linkages of the starch have been broken.41... 

The amylase of Aspergillus oryzae causes a very rapid decrease in the viscosity of its substrates and a very rapid disappearance from its reaction mixtures of products which give color with iodine. When examined under favorable conditions71 at 40° with Lintner s soluble potato starch, the achroic point was reached with highly purified maltase-free amylase when approximately 12% of the glucose linkages of the substrate had been ruptured. 

Quantitative studies have been used to confirm that the attack on amylose is not completely random. A comparison of the action patterns of alpha-amylases from higher plants and mammals shows that they are very different. At the achroic point of hydrolysis of amylose by plant enzymes, about 60% of the saccharides were larger than the... 

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