Significant down-regulation of γ-gliadins has minor effect on gluten and starch properties of bread wheat

Tańska

Cereal Research Communications

2015

Many wheat species and cultivars, independent of genetic markers of hardness, can produce grain with a vitreous, mealy or mixed appearance. This study analyzed selected chemical and physical differences between kernels with a vitreous and mealy appearance, hand-picked from grain of four winter wheat cultivars cultivated in Poland. Separated fractions were examined for protein content and composition, friabilin presence, carotenoids and total phenolic compounds content, specific kernel density, hardness, as well as kernel surface color. It was found that the ratio of vitreous kernels in the cultivars ranged from 39.18% to 76.28%. Vitreous kernels were darker, slightly heavier and harder than mealy kernels. Additionally, these kernels were more abundant in proteins (an average increase of 2.13%, with variation among cultivars from 0.71% to 2.89%). This type of kernels was also richer in phenolic compounds (on average by 4.02%) and less abundant in carotenoids (on average by 4.53%). Mealy (softer) kernels fractured to a finer flour.Keywords: endosperm vitreousness, mealiness, gluten proteins, kernel density, hardness IntroductionWheat cultivars produce grain in which fully vitreous and mealy, or kernels with mixed endosperm structure exist (Horrobin et al. 2003). So-called "piebald" or "yellow berry" kernels can occur in both durum and hexaploid wheat, with mealy and vitreous zones in a sharply-defined area (Dexter et al. 1989). Evers and Bechtel (1988) explained mealy (starchy, chalky, opaque, soft) endosperm as a result of light scattering at the air-starch and air-protein interfaces. Later studies showed that vitreousness is related to the endosperm microstructure (Greffeuille et al. 2006) as well as to kernel color and its mechanical properties (Peterson et al. 2001;Konopka et al. 2005). Soft endosperm is usually linked with a chalky-opaque appearance, and hard endosperm is linked with a glassy-vitreous appearance. Although the vitreousness of endosperm tissue is more typical of hard wheat, 0133-3720/$20.00 © 2015 Akadémiai Kiadó, Budapest * Corresponding author; E-mail: m.tanska@uwm.edu.pl Cereal Research Communications 43(3), pp. 470-480 (2015) DOI: 10.1556/CRC.2014.0048 First published online 21 April 2015 soft wheat cultivars may also produce cohesive hard sections. Morris et al. (2008) found large variations in endosperm microstructure from kernel-to-kernel within pure cultivars of soft, hard and durum wheats. Such variability can also be affected by the vegetation conditions, especially by fertilization (Samson et al. 2005) and climate (Evers and Bechtel 1988). For example, when a soft cultivar of wheat is grown under optimum conditions, it produces vitreous kernels and, in contrast, many hard types of wheat produce opaque/mealy kernels (Pasha et al. 2010). Kernel vitreousness has been found to generally increase with nitrogen fertilization supply (Farm Facts 1997) and can be declined by damp conditions before grain harvest (Sandhu et al. 2009).It was initially thought that starchy and vitreous zone...

Section: Discussionsupporting

confidence: 88%

Differences of some chemicals and physical properties of winter wheat grain of mealy and vitreous appearance

Tańska

Cereal Research Communications

2015

“…Different factors affect wheat end-use quality; most researchers claim that gluten proteins, gliadins and glutenins, are the key elements regarding viscoelastic properties of dough and baking quality (Panozzo et al 2001). Therefore, numerous studies have been carried out to examine the influence of gliadins (Payne et al 1984;Van Lonkhuijsen et al 1992;Huebner et al 1997;Gil-Humanes et al 2012) and glutenins (Payne et al 1984;Branlard and Dardevet 1985;Ng and Bushuk 1988;MacRitchie et al 1991;Blumenthal et al 1995;Huebner et al 1999;Pirozi et al 2008) on the technological quality of wheat. Since Payne et al (1984) determined positive correlation between high-molecular-weight glutenin subunit (HMW-GS) composition and the technological quality of wheat, the studies of end-use wheat quality have been mainly focused on determining the presence or absence of certain glutenin subunits.…”

mentioning

confidence: 99%

Effect of Climate Change on Wheat Quality and HMW Glutenin Subunit Composition in the Pannonian Plain

et al. 2016

Cereal Chem. 93(1):90-99The primary goal of this study is to improve our understanding of the extent of influence of climatic factors in Serbia and high-molecular-weight glutenin subunit (HMW-GS) composition upon wheat end-use quality. In-depth analyses were performed on four bread wheat cultivars that are the most common in agricultural practice in Serbia. Total glutenin content showed significant difference between the production years, in opposition to gliadins. Cluster analysis of different percentages of glutenin and gliadin subunit molecular weight ranges (<40,000, 40,000-80,000, 81,000-120,000, and >120,000) indicated that the year of production and the cultivar did not have a significant effect on the percentage ranges for glutenins. However, they had a considerable impact on the percentage ranges for gliadins. Production year and the interaction of year and cultivar had the strongest influences on the percentage of SDSunextractable polymeric proteins. A synergistic effect of the HMW-GS composition and climatic conditions revealed that all eight samples with HMW-GS composition 2*, 5 + 10, 7 + 9 along with the highest Glu 1 score of 9 (out of a maximum of 10) produced in the year 2011 belonged to two clusters with the best wheat end-use quality. Furthermore, the climate conditions in 2011 made it possible for the wheat cultivars with HMW-GS composition -, 2 + 12, 7 + 9 to possess similar qualities as cultivars with HMW-GS composition 2*, 5 + 10, 7 + 9 produced in 2012. † Corresponding

Comp Rev Food Sci Food Safe

“…hpRNAi ω-1,2-gliadins 6.9 and 45.7 (Altenbach et al, 2019) α/β-, γ -, and ω-gliadins Bread wheat cv "Bobwhite BW2003," "Bobwhite BW208" hpRNAi α/β-, γ -, and ω-gliadins and LMW-GS 60 to 88 (Gil-Humanes et al, 2010;Gil-Humanes et al, 2011;Gil-Humanes, Piston, Barro, & Rosell, 2014;Gil-Humanes, Piston, Gimenez, Martin, & Barro, 2012;Gil-Humanes, Piston, Rosell, & Barro, 2012 (Osorio et al, 2019) (Sánchez-León et al, 2018) leading to 85% reduction in immunoreactivity of mutant lines. This study showed that CRISPR/Cas9 technology can be used to precisely and efficiently reduce the amounts of coeliac-causing epitopes.…”

Section: C-hordeinsmentioning

confidence: 99%

Wheat Seed Proteins: Factors Influencing Their Content, Composition, and Technological Properties, and Strategies to Reduce Adverse Reactions

Rustgi

Shewry

Brouns

et al. 2019

Wheat is the primary source of nutrition for many, especially those living in developing countries, and wheat proteins are among the most widely consumed dietary proteins in the world. However, concerns about disorders related to the consumption of wheat and/or wheat gluten proteins have increased sharply in the last 20 years. This review focuses on wheat gluten proteins and amylase trypsin inhibitors, which are considered to be responsible for eliciting most of the intestinal and extraintestinal symptoms experienced by susceptible individuals. Although several approaches have been proposed to reduce the exposure to gluten or immunogenic peptides resulting from its digestion, none have proven sufficiently effective for general use in coeliac‐safe diets. Potential approaches to manipulate the content, composition, and technological properties of wheat proteins are therefore discussed, as well as the effects of using gluten isolates in various food systems. Finally, some aspects of the use of gluten‐free commodities are discussed.