Rapid Assessment of Glutenin and Gliadin in Wheat by UV Spectrophotometer

Abstract

Traditional breeding of common wheat (Triticum aestivum L.) concentrates largely on the improvement of protein quality because of the importance of protein in end‐product functionality, nutritional value, and economic impact. New, rapid, and inexpensive protein quality tests are required to identify premium quality families from large and diverse early‐generation breeding populations. In this study, a simple method was designed using organic solvents to divide wheat proteins into monomeric‐rich (single‐chain, mostly gliadin), polymeric‐rich (multichain, mostly low‐ and high‐molecular weight glutenin), and total soluble protein (monomeric and polymeric protein). Monomeric‐rich and total soluble protein fractions were quantified at 280 nm with an ultraviolet (UV) spectrophotometer. Protein fractions were expressed in terms of absolute concentration and as a proportion of total soluble protein. A strong linear relationship between the protein concentration in the fractions and the absorbance reading indicated that the method could accommodate a large range of protein fraction concentrations. The specific relationships between quantity and proportion of monomeric/polymeric protein fractions and dough quality tests allowed for the design of an algorithm eliminating poor quality lines from further breeding assessment. Simplicity, reliability, low cost, and a potential for automation could make this UV‐spectrophotometric method suitable for routine use in wheat breeding programs.

Гурил Гурилан Бүтээгдэхүүний Спектроскопийн Судалгааны Зарим Үр Дүнгээс

“…Улаан буудайн гуриланд агуулагдах уургийн нэгдлийг АНУ-ийн Хүнс хөдөө аж ахуйн салбарын эрдэмтэд хэт ягаан-үзэгдэх гэрлийн шингээлтийн спектрийн аргаар судлаж 280 нм-т максимумтай зурвасыг бүртгэсэн байна [4].…”

Effect of Extraction Methods and Wheat Cultivars on Gluten Functionality

“…The L*, a* and b* color coordinates measure the degree of brightness/lightness (L*), redness (a*) and yellowness (b*) of a sample. The 50PI:50PS ratio was measured for wholemeal samples of AC Barrie, Glenlea, AC Corrine and CDC Rama and the soft wheat flour blended with gluten extracts to 14.5% protein content, following the method of Suchy et al [23].…”

“…The CWES wheats had significantly higher dough development time, stability and time to breakdown compared to CWRS wheats indicating stronger dough characteristics. Determinations of the relative amounts of 50% propanol-insoluble (50PI) to propanol-soluble (50PS) gluten components have been used to evaluate the potential of dough strength [23]. Cultivars that have relatively higher ratios of 50PI to 50PS generally have stronger dough mixing properties [23].…”

“…Determinations of the relative amounts of 50% propanol-insoluble (50PI) to propanol-soluble (50PS) gluten components have been used to evaluate the potential of dough strength [23]. Cultivars that have relatively higher ratios of 50PI to 50PS generally have stronger dough mixing properties [23]. The chemical extraction and measurement of the amount of 50PI and 50PS gluten is a rapid and efficient method of estimating dough mixing strength rather than performing the actual dough rheological evaluation.…”

“…The blended flours containing gluten extracted with ethanol had higher ratios of 50PI:50PS as compared to the flours containing gluten extracted with water ( Table 5). The 50PS fraction is rich in monomeric gluten components and contains both gliadins and soluble glutenins while the 50PI fraction is rich in high molecular weight glutenins [23,34]. It is likely that ethanol extraction resulted in increased leaching of monomeric proteins compared to water extraction [8], thus reducing their content in the 50PS fraction and in the ethanol-extracted gluten.…”