Cereal Chem 59:272 - 276.  |  VIEW ARTICLE
Chromatography of Zein on Phosphocellulose and Sulfopropyl Sephadex.

A. Esen. Copyright 1982 by the American Association of Cereal Chemists, Inc. 

Whole zein (60% isopropanol-soluble) and alpha-zein (90% isopropanol-soluble) from corn endosperm were fractionated by ion-exchange chromatography on phosphocellulose and sulfopropyl Sephadex, respectively. Whole zein was dissolved in a lactate-ethylene glycol-isopropanol buffer (pH 3.8) containing mercaptoethanol, loaded on phosphocellulose columns, and eluted by a gradient of NaCl in the same buffer. The elution profile had 12 overlapping peaks. After alpha-zein was reduced and alkylated, it was loaded onto sulfopropyl Sephadex columns in a lactate-isopropanol buffer (pH 3.5) and eluted by a gradient of NaCl in the same buffer. The elution profile included 10 broad peaks, most of which overlapped. The early- eluting peaks of whole zein and alpha-zein contained exclusively the smaller (mol wt 22,000) of the two major size components of zein, as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, whereas the late-eluting peaks contained both components. Isoelectric focusing analysis indicated that all peaks but one were heterogeneous and contained three to 12 charge species; however, one to three charge components predominated in each fraction.