title: Rapid high throughput amylose determination in freeze dried potato tuber samples.
abstract: This protocol describes a high through put colorimetric method that relies on the formation of a complex between iodine and chains of glucose molecules in starch. Iodine forms complexes with both amylose and long chains within amylopectin. After the addition of iodine to a starch sample, the maximum absorption of amylose and amylopectin occurs at 620 and 550 nm, respectively. The amylose/amylopectin ratio can be estimated from the ratio of the 620 and 550 nm absorbance values and comparing them to a standard curve in which specific known concentrations are plotted against absorption values. This high throughput, inexpensive method is reliable and reproducible, allowing the evaluation of large populations of potato clones.
authors.affiliation: USDA-ARS and Department of Horticulture, University of Wisconsin - Madison.
authors.forename: Diego
authors.initials: D
authors.lastname: Fajardo
authors.forename: Sastry S
authors.initials: SS
authors.lastname: Jayanty
authors.forename: Shelley H
authors.initials: SH
authors.lastname: Jansky
mesh_terms: D000688:Amylose / Q000032:analysis* / Q000737:chemistry; D005612:Freeze Drying / Q000379:methods*; D057166:High-Throughput Screening Assays / Q000379:methods*; D035281:Plant Tubers / Q000201:enzymology*; D011198:Solanum tuberosum / Q000201:enzymology*
chemical_list: D000688:Amylose