A Rapid Spectrophotometric Assay for Measuring Functional Protein in Wheat

摘要

The development of premium wheat cultivars requires screening of large and diverse sets of early generation wheat breeding material for the desired quality traits. The objective of this study was to develop a rapid and an inexpensive protein quality test. The procedure was developed to extract and measure the concentration of monomeric-rich, glutenm-rich and total soluble protein using a UV-spectrophotometer at 280 nm. Each protein fraction was quantified using a UV-spectrophotometer as well as by RP-HPLC with a UV detector at 280 nm. Positive high correlations (r=0.94) were obtained between the concentration of glutenin-rich protein fraction measured by RP-HPLC and by UV-spectrophotometer. Wheats with a high concentration of glutenin correlated highly to farinograph and mixograph dough strength parameters. This simple and rapid spectrophotometric assay was used to screen a large population of early generation wheat (F_4) and compare the results to traditional quality jests typically carried out atthis stage of screening. Wheats with overall weak dough-strength were eliminated using an algorithm that took into account the concentration and proportion of gliadin and glutenin protein in flour or whole meal. The results compared well to lines eliminated based on dough quality parameters. The UV-spectrophotometric procedure is simple, inexpensive and has the potential for automation.