Chain Length Distribution of Amylopectins of Several Single Mutants and the Normal Counterpart, and Sugary‐1 Phytoglycogen in Maize (Zea mays L.)

Abstract

Abstractβ‐Limit dextrins of starches of normal (nonmutant), amylose‐extender (ae), dull (du), sugary‐2 (su2) and waxy (wx) maize, and phytoglycogen of sugar‐1 (su1) maize were prepared. The β‐limit dextrins were successively debranched by isoamylase and pullulanase, and followed by quantitative gel‐filtration.The ratio of A to B chains for the ae starch appeared to be high and that for su1 phytoglycogen was low. The ratio of short B to long B chains for the du starch was high and that for the ae starch appeared to be low. The phytoglycogen did not contain long B chains. The unit chain‐length distribution of amylopectins of the normal, wx, and su2 starches were similar. Fine structures of maize amylopectins and su1 phytoglycogen were modeled and described.