Amylase during the growth and ripening of grains

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Abstract
In wheats, oats and barley, as in rye, whole amylase is found with its 3 functions intact (liquefying, dextrinizing and saccharifying) from the moment the grain is formed immediately after blossoming. As the grain ripens, the liquefying and dextrinizing functions gradually disappear and the saccharifying function undergoes partial decrease. This disappearance of the liquefying and dextrinizing functions is above all of an adsorptive nature and can be counteracted by eleuto-substances (peptone or NaCl). The latter give better results with wheat at conens. of 0.5-1%. The disappearance of dextrinizing and liquefying functions could not be counteracted by the action of papain. The activities of the various functions of amylase and the speed of their diminution and disappearance, as also their liberation by the action of eleuto-substances, are an individual trait of cereal species. With barley, which possesses the highest quantity of sisto-substances, the diminution of the various functions of amylase commences earliest, i.e., during the early stages of ripening. The views that [alpha]-amylase is formed only during the germination of grains, and that the gradual total loss of dextrinizing power of amylase is due to oxidation of ascorbic acid, were not confirmed by the authors'' previous expts. on rye or by the present ones on the development of amylase in ripening barley, wheat and oats.