The Amylase System of Rice Grain during Ripening and Germination

Abstract

THE formation and properties of - and -amylases in germinating grains have been frequently studied by many investigators. Some workers¹ believe that dormant grains contain only -amylase which increases during germination, while -amylase appears only during sprouting. Others² consider that the increase in amylolytic activity during germination is not a fresh enzyme formation, but is due to an activation by an activator of organic nature, amylokinase, which arises during the process of germination, or to an increase in the soluble part of the amylase, especially in the case of the -component, which increase is based on proteolytic decomposition. Our researches on the amylolytic changes during ripening and germination of rice grains have thrown fresh light on this important question. The results thus far obtained may be briefly summarized as follows.