Zeins from Zea mays L cv. Maya and coixins from Coix lacryma-jobi L. cv. Adlay were fractionated to obtain a-, ß-, and ?-zein and a-, ß-, and ?-coixin. The a-coixins were composed of 4 polypeptide classes of 27 kDa (C1), 25 kDa (C2), 17 kDa (C4) and 15 kDa (C5) with solubility properties very similar to those of the 22 kDa and 19 kDa a-zeins. Like the a-zeins, the C1 and C2 a-coixins corresponded to 80% of total Coix prolamins. The fraction corresponding to ?-coixin contained only one protein band of 22 kDa (C3). This coixin fraction has solubility properties similar to those of ?-zein and represents 15% of the total coixin. The ß-zein fraction was composed of a major 17 kDa protein band, while the ß-coixin fraction consisted of a mixture of a- and ?-coixins.