Identification of oat (<Emphasis Type="Italic">Avena sativa</Emphasis>) and buckwheat (<Emphasis Type="Italic">Fagopyrum esculentum</Emphasis>) proteins and their prolamin fractions using two-dimensional polyacrylamide gel electrophoresis

Total (non-fractionated) kernel proteins and the prolamin fraction (soluble in 75% ethanol) were extracted from oat (Avena sativa) var. Flämingstern kernel and from buckwheat (Fagopyrum esculentum) var. Kora kernel. As for buckwheat, extraction was effective only after kernel dehulling which allowed the removal of tannins and phenolic compounds that form complexes with proteins during extraction. The extracted proteins were analyzed using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Gels of the prolamin fractions of oat and buckwheat were used as reference gels in order to detect prolamins on gels of total kernel proteins. The occurrence of 26 and 29 spots corresponding to prolamins was found on gels of total oat proteins and on gels of total buckwheat proteins, respectively. The electrophoretic images of oat and buckwheat prolamins revealed organized subregions containing spots with similar isoelectric points (pI) and various molecular weights (MW), mostly on oat prolamin gels and spots of similar molecular weights with various isoelectric points, mostly on buckwheat prolamin gels. Such organized subregions can be used as identifiers for the occurrence of prolamin fractions in total proteins (particularly as regards buckwheat proteins).