Search Results (75)

The technological properties of durum wheat grain are determined by prolamins (gliadins and glutenins). Information on the allelic composition of key loci remains incomplete despite existing global studies examining prolamin variability. This highlighted the need to study these traits in durum wheat in Kazakhstan. The effects of specific gliadin components with high- and low-molecular-weight glutenin fractions on gluten quality are also not fully clarified. This study aimed to characterise allelic diversity at prolamin-coding loci and evaluate associated grain quality traits. Using native and denaturing SDS-electrophoresis, 181 tetraploid wheat accessions from Kazakhstan, an International germplasm collection, and 26 breeding lines were analysed for allelic variation and associations with protein content, gluten content, gluten index, and SDS-sedimentation. The γ45 gliadin component and Glu-A3a allele were positively associated with SDS-sedimentation and gluten index, while Glu-B3b had a negative effect. Distinct prolamin profiles were observed among accessions from different ecological and geographical locations. These results support the selection of superior durum wheat genotypes and enable the identification of favourable allele combinations at the Gli-1, Gli-2, Glu-1, and Glu-3 loci in cultivars from Kazakhstan. Comparison with global tetraploid wheat germplasm collections demonstrates unique genetic diversity in genotypes, providing a valuable basis for breeding programs aimed at improving grain and gluten quality in durum wheat in Kazakhstan and Central Asian countries. Full article

To address the limitations of traditional wheat quality breeding, this study developed a Wheat Quality Molecular Marker Selection System (QMMS) by integrating key genetic loci controlling core quality traits: grain protein content (GPC), grain hardness (GH), and high-molecular-weight glutenin subunits (HMW-GS). The QMMS comprises three KASP markers (Kgpc-2B, Kgpc-2D, Kgpc-4A) and two duplex KASP (dKASP) markers (Pin-ab, Glu-AD), enabling cost-effective (≈5 CNY per sample) and high-throughput genotyping. Systematic validation was conducted using four panels of materials: representative varieties, breeding nursery materials, regional trial materials from the Middle and Lower Reaches of the Yangtze River, and advanced lines from four cooperative institutions. Results showed that (1) the QMMS accurately distinguished quality types of representative varieties: strong-gluten varieties carried five or more strong-gluten–favorable alleles, while weak-gluten varieties harbored five or more weak-gluten favorable alleles; (2) in breeding nursery materials, quality traits increased significantly with the number of aggregated strong-gluten favorable alleles, and 48.15% of strong-gluten candidates met strong- and medium-strong-gluten standards; (3) in regional trial materials, 15.25% (36/236) and 1.69% (4/236) of lines carried ≥5 strong-gluten and weak-gluten favorable alleles, with low utilization of Kgpc-2D and Pina/Pinb favorable alleles (<30%); and (4) the QMMS screened 273 strong-gluten and 27 weak-gluten candidates for cooperative institutions, matching their breeding focuses. In conclusion, the QMMS provides reliable technical support for precise and efficient wheat quality breeding. Full article

The detection of allergens is essential for ensuring food safety, protecting public health, and providing accurate information to consumers. Wheat (Triticum aestivum L.) and maize (Zea mays L.) are recognized as important food allergens. In this study, novel PCR methods were developed for the reliable detection of wheat and maize allergens, including wheat high-molecular-weight glutenin subunit (HMW-GS) and low-molecular-weight glutenin subunit (LMW-GS), as well as three maize allergens, namely, Zea m 14, Zea m 8, and zein. Wheat and maize genomic DNA, as well as allergen genes, were examined during 60 min of baking at 180 °C and 220 °C. Agarose gel electrophoresis revealed degradation of genomic DNA and amplified PCR fragments in correlation with increasing baking temperature and time. For each target gene, the best primers were identified that could detect HMW-GS and LMW-GS genes in wheat samples and Zea m 14, Zea m 8, and zein genes in maize samples after baking at 220 °C for 60 min and 40 min, respectively. The results indicate that these PCR methods can be used for the reliable and sensitive detection of wheat and maize allergens in processed foods. Full article

Wheat is a crucial crop for human nutrition, and the demand for high-quality indicators within the “from farm to fork” concept is increasing. Based on this premise, this study examined how, at the farm level, the fertilization system can influence key quality indicators relevant to wheat production and final products. This research was conducted under specific conditions of the Western Plain of Romania at the Agricultural Research and Development Station (ARDS), Lovrin, during 2015–2017. Fertilization involved the autumn application of phosphorus (concentrated superphosphate; 0, 40, 80, 120, 160 kg ha⁻¹ active substance, a.s.) and potassium (potassium chloride; 0, 40, 80, 120 kg ha⁻¹ a.s.). Nitrogen (ammonium nitrate; 0, 30, 60, 90, 120 kg ha⁻¹ active substance) was applied in spring in two stages. The combination of these three fertilizers resulted in 18 fertilized variants (T2 to T19), tested alongside an unfertilized control (T1). The experimental variants were arranged in four randomized replications. Grain quality was assessed based on protein content (PRO, %), gluten (GLT, g 100 g⁻¹), gliadins (Gliad, %), glutenins (Glut, g 100 g⁻¹), high-molecular-weight glutenins (HMW, g 100 g⁻¹), low-molecular-weight glutenins (LMW, g 100 g⁻¹), and the gliadin/glutenin ratio (Gliad/Glut). Compared to the average values for each indicator across the experiment, certain variants produced values above the mean, with statistical significance. Variant T16 stood out by producing values above the mean for all indicators, with statistical confidence. Multivariate analysis showed that five indicators with very strong (PRO, GLT) and strong (HMW, Glut, LMW) influence grouped in PC1, while two indicators (Gliad, Gliad/Glut) with very strong and strong influence grouped in PC2. The analysis revealed varying levels of correlation between the applied fertilizers, with nitrogen (N) showing very strong and strong correlations with most indicators, while phosphorus and potassium showed moderate-to-weak correlations. Regression analysis generated mathematical models that statistically described how each indicator varied in relation to the fertilizers applied. Full article

The broader application of gluten in both the food and non-food industries is limited by its lack of functional properties, such as solubility, foaming ability, and rheological characteristics. This study aimed to evaluate the physicochemical properties of proteins in various gluten products and to investigate the effects of enzymatic hydrolysis and ultrasound (US) treatment on wheat flour gluten yield, gliadin–glutenin complex structure, and gelation properties. The gelation properties of wheat gluten (GL)/pea protein (PP) treated with US and transglutaminase (TG) were studied. The results demonstrated that the ratio of low- to high-molecular-weight components in gliadins and glutenins significantly influenced the quality of commercial gluten products. A 90 min treatment of wheat flour with 24 TGU/100 g increased the yield of high-quality gluten by 32% while reducing the gliadin content by up to 6-fold. Additionally, a 30 min US treatment of 18–20% pure gluten suspensions yielded a sufficiently strong gel. The addition of PP isolate (80% protein) improved the texture of gluten gels, with the best results observed at a GL:PP ratio of 1:2. The application of TG increased the hardness, consistency, and viscosity of GL-PP gels by an average of 5.7 times while reducing stickiness. The combined TG and US treatments, along with the addition of PP, notably increased the levels of lysine, isoleucine, and tryptophan, thereby enhancing both the nutritional quality and amino acid balance of the final product. Full article

Global climate change poses a significant threat to wheat (Triticum aestivum L.) production due to rising temperatures. This study aimed to investigate the impact of high temperatures on wheat yield, thousand kernel weight (TKW), colour, and protein composition to inform breeding strategies for heat tolerance. Two field experiments were conducted: one at three locations in Australia (Horsham, (Vic) Narrabri, (NSW) and Merredin, (W.A.)) in 2019, involving two wheat varieties (Berkut (high-heat-tolerant) and Sokoll (medium-heat-tolerant)) sown at normal (TOS1) and late (TOS2) sowing times; and a second experiment at Narrabri in 2019 and 2020, involving three wheat varieties (Cobra (heat-sensitive), Flanker (high-heat-tolerant) and Suntop (medium-heat-tolerant)) sown at normal (TOS1) and late (TOS2) sowing times. There were reductions in yield and TKW under high temperatures (p < 0.05), particularly in late sowing conditions. The glutenin/gliadin ratio decreased, affecting dough strength and elasticity, especially at Merredin. Heat-tolerant varieties like Flanker and Suntop maintained protein quality, with an increase in the glutenin/gliadin ratio, under high temperature. These findings highlight the necessity for breeding heat-tolerant wheat varieties that can sustain both yield and quality. Future research should focus on genetic traits for heat tolerance, advanced molecular techniques, and interdisciplinary approaches to ensure sustainable wheat production in a changing climate. Full article

Background: The low molecular weight glutenin subunits (LMW-GS) of wheat have great effects on food processing quality, but the resolution of LMW-GS and the scoring of their alleles by direct analysis of proteins are difficult due to the larger number of expressed subunits and high similarity of DNA sequences. It is important to identify and classify the LMW-GS genes in order to recognize the LMW-GS alleles clearly and develop the functional markers. Methods: The LMW-GS genes registered in GenBank were searched at NCBI, and 593 Glu-3 genes with complete coding sequences were obtained, including 146 Glu-A3, 136 Glu-B3, and 311 Glu-D3. Sequence analysis and characterization of DNA and deduced amino acids were performed using the software DNAman. Results: The alignment and classification showed that there were at least 9 genes with 69 allelic variants at the Glu-A3 locus, 11 genes with 64 allelic variants at the Glu-B3 locus, and 10 genes with 96 variants at the Glu-D3 locus, respectively. Furthermore, the specificity of some Glu-3 genes and their variations was analyzed. Conclusions: The results were beneficial to understanding the LMW-GS genes fully and to developing the functional markers and will provide a theoretical reference for the quality improvement of wheat variety. Full article

Non-satisfactory bread-making quality in wheat, a Tajik staple, hampers food security in Tajikistan and calls for plant breeding efforts. Here, methods were searched for to study grain protein composition, which is of use for Tajik plant breeding to improve bread-making quality. Size-exclusion high-performance liquid chromatography (SE-HPLC) was used to determine protein composition in 22 wheat varieties and breeding lines grown in two locations, which were then compared with the specific protein composition evaluated using electrophoresis and previous results from Tajik breeding and farmer-grown wheat. As Tajik wheat generally showed a large variation in high-molecular-weight glutenin subunit (HMW-GS) composition, with several allelic variants in the same line, single-seed selection was required when using this methodology in breeding for improved bread-making quality, and such an evaluation willalso result in more homogenous lines for protein composition. SE-HPLC was found to be a suitable tool to evaluate protein composition in the current Tajik wheat material with a heterogeneous protein composition, which might be advantageous for adaptation to the local and future climate. However, more easy-to-handle and high-throughput methods, e.g., marker-assisted selection, could be preferable alternatives for studying protein composition in wheat and for use in breeding for increased bread-making quality to increase food security in Tajikistan. Full article

Polyploid wheats include a group of tetraploids known as Timopheevii (A^uA^uGG), which are represented by two subspecies: Triticum timopheevii ssp. timopheevii (cultivated) and Triticum timopheevii ssp. araraticum (wild). The combined use of electrophoretic (SDS-PAGE) and chromatographic (RP-HPLC) techniques carried out on high-molecular-weight glutenin subunits (HMW-GSs) permitted the association of different x- and y-type subunits to the A and G genomes and the assessment of allelic variation present at corresponding loci. The results also revealed that in both subspecies, accessions are present that possess expressed y-type subunits at the Glu-A1 locus. Genes corresponding to these subunits were amplified and amplicons corresponding to x- and y-type genes associated with the A genome were detected in all accessions, including those without expressed x- and y-type subunits. The comparison with genes of polyploid wheats confirmed the structural characteristics of typical y-type genes, with the presence of seven cysteine residues and with hexapeptide and nonapeptide repeat motifs. The identification of wild and cultivated T. timopheevii with both x- and y-type glutenin subunits at the Glu-A1 and Glu-G1 loci represents a useful source for the modification of the allelic composition of HMW-GSs in cultivated wheats with the ultimate objective of improving technological properties. Full article

High-molecular-weight glutenin subunits (HMW-GS) are an important component of total cereal proteins in wheat. It is closely related to the processing quality of flour. Here, we analyzed allelic variations at the Glu-1 locus in 163 wheat accessions from Hubei Province, China with SDS-PAGE. Among the 15 alleles detected, alleles 1, 7+8, and 2+12 were the major alleles, and 7, 6+8, and 2+10 were rare alleles. The breeding lines had higher genetic diversity than the commercial varieties. Alleles 7 and 6+8 significantly reduced the grain protein content and wet gluten content of wheat. The “1, 7+9, 5+10” and “1, 14+15, and 2+12” allelic combinations significantly increased the grain protein content, hardness index, test weight, and wet gluten content of wheat. Alleles 7+9, 14+15, and 5+10 were identified as alleles related to high wheat quality. The “1, 7, 5+10”, “1, 6+8, 5+10”, “null, 7+9, 2+12”, “1, 14+15, 2+12”, and “1, 7+9, 5+10” allelic combinations had greater effects on wheat grain quality traits. These results demonstrate the effects of HMW-GS on wheat grain quality traits and provide a reference for the genetic improvement of wheat quality. Full article

Wheat allergy dependent on augmentation factors (WALDA) is the most common gluten allergy in adults. IgE-mediated sensitizations are directed towards ω5-gliadin but also to other wheat allergens. The value of the different in vitro cellular tests, namely the basophil activation test (BAT) and the active (aBHRA) and passive basophil histamine-release assays (pBHRA), in the detection of sensitization profiles beyond ω5-gliadin has not been compared. Therefore, 13 patients with challenge-confirmed, ω5-gliadin-positive WALDA and 11 healthy controls were enrolled. Specific IgE (sIgE), skin prick tests, BATs, aBHRA, and pBHRA were performed with allergen test solutions derived from wheat and other cereals, and results were analyzed and compared. This study reveals a distinct and highly individual reactivity of ω5-gliadin-positive WALDA patients to a range of wheat allergens beyond ω5-gliadin in cellular in vitro tests and SPT. In the BAT, for all tested allergens (gluten, high-molecular-weight glutenin subunits, α-amylase/trypsin inhibitors (ATIs), alcohol-free wheat beer, hydrolyzed wheat proteins (HWPs), rye gluten and secalins), basophil activation in patients was significantly higher than in controls (p = 0.004–p < 0.001). Similarly, significant histamine release was detected in the aBHRA for all test substances, exceeding the cut-off of 10 ng/mL in all tested allergens in 50% of patients. The dependency of tests on sIgE levels against ω5-gliadin differed; in the pBHRA, histamine release to any test substances could only be detected in patients with sIgE against ω5-gliadin ≥ 7.7 kU/L, whereas aBHRA also showed high reactivity in less sensitized patients. In most patients, reactivity to HWPs, ATIs, and rye allergens was observed. Additionally, alcohol-free wheat beer was first described as a promising test substance in ω5-gliadin-positive WALDA. Thus, BAT and aBHRA are valuable tools for the identification of sensitization profiles in WALDA. Full article

Genetic variation in high molecular weight glutenin (HMW-GS) genes is tightly linked with the breadmaking quality of wheat. Hundreds of different alleles have been identified in HMW-GS genes worldwide. Such huge variability makes it difficult to distinguish them using conventional genotyping methods (for example, SDS-PAGE, SNP detection, etc.). Here, we exploited the nanopore amplicon sequencing technique (Amplicon-Seq) to uncover genetic variants distributed along the full-length sequence of six HMW-GSs, including the promoter and protein-coding regions. We analyzed 23 wheat accessions for allelic variants of HMW-GSs using the Amplicon-Seq and SDS-PAGE methods. We obtained sufficient (>50×) target gene coverage by ONT reads in just one hour. Using the obtained data, we identified numerous single nucleotide polymorphisms and InDels in the protein coding and promoter regions. Moreover, Amplicon-Seq allowed for the identification of new alleles (Glu-A1x1-T) of the Glu-1Ax gene that could not be recognized by SDS-PAGE. Collectively, our results showed that Amplicon-Seq is a rapid, multiplexed, and efficient method for high-throughput genotyping of full-length genes in large and complex genomes. This opens new avenues for the assessment of target gene variation to select novel alleles and create unique combinations of desirable traits in plant breeding programs. Full article

Immunogenic peptides from wheat gluten can be produced during digestion, which are difficult to digest by gastrointestinal proteases and negatively affect immune responses in humans. Gluten intolerance is a problem in countries where wheat is a staple food, and a gluten-free diet is commonly recommended for its treatment and prevention. Enzyme approaches for degradation of the peptides can be considered as a strategy for its prevention. Here, we isolated a gluten-degrading bacterium, Bacillus amyloliquefaciens subsp. plantarum, from wheat grains. The culture conditions for enzyme production or microbial use were considered based on gluten decomposition patterns. Additionally, the pH range for the activity of the crude enzyme was investigated. The bacterium production of gluten-degrading enzymes was temperature-dependent within 25 °C to 45 °C, and the production time decreased with increasing culture temperature. However, it was markedly decreased with increasing biofilm formation. The bacterium decomposed high-molecular-weight glutenin proteins first, followed by gliadin proteins, regardless of the culture temperature. Western blotting with an anti-gliadin antibody revealed that the bacterium decomposed immunogenic proteins related to α/β-gliadins. The crude enzyme was active in the pH ranges of 5 to 8, and enzyme production was increased by adding gliadin into the culture medium. In this study, the potential of the B. amyloliquefaciens subsp. plantarum for gluten-degrading enzyme production was demonstrated. If further studies for purification of the enzyme specific to the immunogenic peptides and its characteristics are conducted, it may contribute as a strategy for prevention of gluten intolerance. Full article

To develop teff-based food products with acceptable quality, the composition, structure, and properties of teff protein fractions should be better understood. In this study, teff proteins were extracted, and their protein composition, structure, and properties were calculated, analyzed, and compared with those of wheat gliadin and glutenin. Results showed that teff flour contained 9.07% protein, with prolamin as its main protein fraction. The isoelectric points of albumin, globulin, prolamin, and glutelin were at pH 3.6, 3.0, 4.4, and 3.4, respectively. Teff prolamin and glutelin showed a significant difference in amino acids and free energy of hydration compared to wheat gliadins and glutenins. The protein chain length of teff prolamins was smaller than that of wheat gliadins, and teff glutelins lacked high molecular weight glutelin subunits. Teff prolamin had the highest α-helices content (27.08%), whereas no random coils were determined, which is different from wheat gliadin. Teff glutelin had a lower content of β-turn than wheat glutenin, and no α-helices were determined in it. Teff prolamin and glutelin had lower disulfide bond content and surface hydrophobicity. Teff prolamin had significantly higher thermal stability than wheat gliadin, whereas the thermal stability of teff glutelin was significantly lower than that of wheat glutenin. Full article

Many varieties of soft wheat in China cannot fully satisfy the requirements of making high-quality cakes due to their undesirable protein properties, which leads to shortages of high-quality soft wheat flour. Therefore, a modification of soft wheat protein is essential for improving the quality of soft wheat and thus improving cake quality. In order to modify the protein properties of soft wheat used for cake production, superheated steam (SS) was used to treat soft wheat grains at 165 °C and 190 °C for 1, 2, 3, 4, and 5 min, respectively, followed by the milling of wheat grains to obtain refined wheat flour. The properties of proteins and cakes were analyzed using refined wheat flour as materials. First, changes in the structures of wheat proteins were analyzed by determining the solubility, molecular weight distribution and secondary structure of proteins in wheat flour. Secondly, changes in the functional properties of proteins were analyzed by determining the foaming properties and emulsifying properties of proteins in wheat flour. Finally, the specific volume and texture of cakes with wheat flour milled from SS-treated wheat were analyzed. At the initial stage of SS treatment, some of the gliadin and glutenin aggregated, and the gluten macro-polymer (GMP) contents increased. This allowed a more stable gluten network to form during dough kneading, leading to an improvement in dough elasticity. In addition, a short time period (1–3 min) of SS treatment improved the emulsifying properties and foaming ability of wheat protein, which helped to improve the specific volume and texture of cakes. Increasing the SS temperature from 165 °C to 190 °C reduced the optimal treatment time needed to improve cake quality from 3 min to 1 min. SS treatment for longer time (>3 min) periods led to severe protein aggregation and a decrease in the foaming ability and emulsifying properties of protein, which led to a deterioration in the cake quality. Thus, SS treatment at 165 °C for 1–3 min and 190 °C for 1 min could be a suitable method of improving the physicochemical properties of soft wheat used to make cakes with high specific volumes and good texture. Full article