Isolation and characterisation of wheat flour proteins. I.—separation of salt‐ and acetic acid‐dispersible proteins by gel filtration, polyacrylamide gel electrophoresis, and sucrose gradient ultracentrifugation

Abstract

Proteins extracted from wheat flour with 0.01 M-sodium pyrophosphate buffer, pH 7.0, and with 0.05 M-acetic acid were centrifuged, dialysed against 0.005 hr-sodium acetate buffer pH 4.1, concentrated by ultrafiltration at 4', and lyophylised. The proteins were dispersed in 0.005 M-sodium acetate buffer pH 4.1 and fractionated on Sephadex G-IOO and Sephadex G-zoo columns. Based on separation according to average mol. wt. on Sephadex G-100, the pyrophosphate-dispersible proteins contained eight, and the following acetic acid-dispersible proteins six fractions. Proteins extracted directly with 0.05 M-acetic acid were separated into seven fractions. The distribution of protein moieties of different average molecular-size ranges is detailed and shown to be different in the different extracts. Aggregation and disaggregation phenomena were observed during repeated re-chromatography of high-and intermediate-molecular weight proteins. Ultra-centrifugation in a stepwise sucrose gradient at 45,000 g. at 4' and fractionation by polyacrylamide-gel electrophoresis separated the protein into slow-moving, intermediate-and high-molecular weight moieties. The relative distribution of these moieties was correlated with the mol. wt. of the fractions eluted from Sephadex columns.

Comparing Functional Properties of Gluten From Einkorn and Common Wheat

“…Określano skład frakcyjny układu białkowego mąki z samopszy i pszenicy zwyczajnej, posługując się metodą ekstrakcji trójstopniowej wg Coatesa i Simmondsa [9] w modyfikacji Jankiewicza [14], wyodrębniając ekstrakt albumin i globulin w 0,01 M buforze pirofosforanowym o pH 7,0, ekstrakt prolamin w 0,05 M kwasie octowym oraz ekstrakt glutelin w 0,1 M NaOH.…”