Cereal Chem 53:355 - 364. | VIEW
Starches of Endosperms Possessing Different Alleles at the Amylose-Extender Locus in Zea mays.
L. D. L. Garwood, J. C. Shannon, and R. G. Creech. Copyright 1976 by the American Association of Cereal Chemists, Inc.
Starches from seven independently occurring amylose-extender (ae) maize (Zea mays L.) alleles, named B2, B3, il, i2, M1, M2, and Ref, were compared. Apparent amylose content of il and i2 starch granules averaged 56.6% and differed from that of the other five alleles which averaged 64.5%. Starch granules were subjected to aqueous leaching in boiling water, and the 40% of the total starch solubilized was separated into butanol complexing and noncomplexing fractions. Amylose was preferentially leached from the granules but not all was solubilized. The butanol complexing fraction from all ae alleles had similar physiocochemical properties which were typical of amylose. Properties of the butanol noncomplexing fraction were consistent with the theory that this material was a mixture of short-chain amylose and typical amylopectin. The i1 and i2 noncomplexing fractions had a lower percentage conversion to maltose by beta- amylase, a lower apparent amylose content, a lower polysaccharide-iodine absorbance maximum, and a higher ratio of total to reducing glucose units than the other five ae alleles. The il and i2 starches appeared to have the same components as the other ae alleles but with lesser amounts of short-chain amylose. Polysaccharide composition of the starch for all ae alleles examined was similar to that produced by the allele currently used in amylomaize production. Starches of the B2, B3, M1, M2, and Ref alleles would be suitable for current industrial utilization, and the il and i2 alleles might also be useful.