Comparison of intestinal absorption of soybean protein isolate-, glutenin- and peanut protein isolate-bound Nε-(carboxymethyl) lysine after in vitro gastrointestinal digestion.

Advanced glycation end products (AGEs), a heterogeneous compound existed in processed foods, are related to chronic diseases when they are accumulated excessively in human organs. Protein-bound Nε-(carboxymethyl) lysine (CML) as a typical AGE, is widely determined to evaluate AGEs level in foods and in vivo. This study investigated the intestinal absorption of three protein-bound CML originated from main food raw materials (soybean, wheat and peanut). After in vitro gastrointestinal digestion, the three protein-bound CML digests were ultrafiltered and divided into four fractions: less than 1 kDa, between 1 and 3 kDa, between 3 and 5 kDa, greater than 5 kDa. Caco-2 cell monolayer model was further used to evaluate the intestinal absorption of these components. Results showed that the absorption rates of soybean protein isolate (SPI)-, glutenin (Glu)-, peanut protein isolate (PPI)-bound CML were 30.18%, 31.57% and 29.5%, respectively. The absorption rates of components with MW less than 5 kDa accounted for 19.91% (SPI-bound CML), 22.59% (Glu-bound CML), 23.64% (PPI-bound CML), respectively, and these samples were absorbed by paracellular route, transcytosis route and active route via PepT-1. Taken together, these findings demonstrated that all three protein-bound CML digests with different MW can be absorbed in diverse absorption pathways by Caco-2 cell monolayer model. This research provided a theoretical basis for scientific evaluation of digestion and absorption of AGEs in food.

Urinary excretion of gluten immunoreactive peptides as an indicator of gastrointestinal function after fasting and dietary provocation in healthy volunteers.

Introduction: Understanding intestinal permeability is paramount for elucidating gastrointestinal health and pathology. The size and nature of the molecule traversing the intestinal barrier offer crucial insights into various acute and chronic diseases, as well as the evolution of some conditions. This study aims to assess the urinary excretion kinetics of gluten immunogenic peptides (u-GIP), a unique class of dietary peptides detectable in urine, in volunteers under controlled dietary conditions. This evaluation should be compared to established probes like lactulose, a non-digestible disaccharide indicative of paracellular permeability, and mannitol, reflecting transcellular permeability. Methods: Fifteen participants underwent simultaneous ingestion of standardized doses of gluten (10 g), lactulose (10 g), and mannitol (1 g) under fasting conditions for at least 8 hours pre-ingestion and during 6 hours post-ingestion period. Urine samples were collected over specified time intervals. Excretion patterns were analyzed, and correlations between the lactulose-to-mannitol ratio (LMR) and u-GIP parameters were assessed. Results: The majority of u-GIP were detected within the first 12 hours post-ingestion. Analysis of the variability in cumulative excretion across two sample collection ranges demonstrated that lactulose and u-GIP exhibited similar onset and excretion dynamics, although GIP reached its maximum peak earlier than either lactulose or mannitol. Additionally, a moderate correlation was observed between the LMR and u-GIP parameters within the longest urine collection interval, indicating potential shared characteristics among permeability pathways. These findings suggest that extending urine collection beyond 6 hours may enhance data reliability. Discussion: This study sheds light on the temporal dynamics of u-GIP in comparison to lactulose and mannitol, established probes for assessing intestinal permeability. The resemblance between u-GIP and lactulose excretion patterns aligns with the anticipated paracellular permeability pathway. The capacity to detect antigenic food protein fragments in urine opens novel avenues for studying protein metabolism and monitoring pathologies related to the digestive and intestinal systems.

The Effects of Gluten on Weight Gain, Hematological, Biochemical, and Various Endocrinological Parameters.

BACKGROUND/AIMS:  This study is aimed to compare the effects of nutrition which has been enriched with different amounts of gluten to gluten-free diets on weight gain, diabetogenic state, hematological, and biochemical parameters. MATERIALS AND METHODS:  A total of 40 newly weaned male Wistar albino rats used in the study were randomized into 4 different groups based on the gluten rations they were given. Following 12 weeks of diet they were killed and intracardiac blood samples were collected. Groups were identified as group 1 (n = 10): control group; normal rat ration containing wheat, group 2 (n = 10): gluten-free diet, group 3 (n = 10): ration containing medium level of gluten (normal rat diet+6% vital gluten) and group 4 (n = 10): ration containing high level of gluten (normal rat diet+12% vital gluten). RESULTS:  In groups 3 and 4, high-density lipoprotein was found to be higher than the other 2groups. However, when group 2 results were compared to the other groups; the highest T3, T4, creatinine and B12 levels and the lowest gluten-specific IgE level were observed. alanine aminotransferase and aspartate aminotransferase levels were found to be higher in group 1 compared to the other 3 groups. No statistically significant difference was detected between the groups in terms of other parameters. CONCLUSION:  This study provides evidence that a gluten-containing diet does not cause weight gain, has no diabetogenic effect, and also does not adversely affect general health in relation to hematological, biochemical, and various endocrinological parameters.

Evaluation of Sourdough Bread and Its Potential Use in Support of the Treatment of Chronic Non-Communicable Diseases.

Gastrointestinal disorders dysregulate the biochemical environment of the gastrointestinal tract by altering pH conditions during the gastric phase of digestion or by reducing the secretion of pancreatin during the intestinal part of the process. Ingested functional food could therefore lose some of its health-promoting potential apart from its nutritional value. In this work, we aimed to manufacture bread marked by decreased gluten content, using a commercial or laboratory sourdough, that could be appropriate for patients afflicted with wheat allergy, hypertension and pancreatic malfunctions. A reference sample (no sourdough) was prepared alongside wheat and wheat-rye bread samples-produced with either commercial or laboratory sourdough (L. plantarum BS, L. brevis 1269, L. sanfranciscensis 20663). We measured the QQQPP allergen content (ELISA) in bread extracts digested in vitro and determined how these extracted components affect the level of active angiotensin and alpha amylase (spectrophotometry). We then elucidated how these properties changed when physiological digestion conditions (pH and pancreatin activity) were disturbed to mimic gastric hyperacidity, hypochlorhydria or exocrine pancreatic insufficiency. The key finding was that every tested type of bread produced with laboratory sourdough exhibited pronounced angiotensin-converting enzyme inhibition. The effect was preserved even in dysregulated digestive conditions. The use of laboratory sourdough prevented an increase in allergenicity when pancreatin was restricted as opposed to the commercial sourdough, which surpassed the reference sample reading at 50% pancreatin. No statistically consistent link was reported when the inhibition of alpha amylase was assayed. In conclusion, functional bread manufactured with sourdough composed of L. plantarum BS, L. brevis 1269, and L. sanfranciscensis 20663 was shown to be potentially capable of contributing to the treatment against hypertension as evidenced by in vitro research. It was also moderately safer with regard to its allergenicity.

Digesting gluten with oral endopeptidases to improve the management of celiac disease.

In our editorial, we want to comment on the article by Stefanolo et al titled "Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet". Celiac disease is an immune-mediated disorder triggered by dietary gluten in genetically predisposed individuals. Although avoiding gluten can permit patients to live symptom-free, ongoing voluntary or involuntary exposure to gluten is common and associated with persistent villous atrophy in small bowel mucosa. As villous atrophy predisposes patients to life threatening complications, such as osteoporotic fractures or malignancies, therapeutic adjuncts to gluten-free diet become important to improve patients' quality of life and, if these adjuncts can be shown to improve villous atrophy, avoid complications. Oral administration of enzyme preparations, such as endopeptidases that digest gluten and mitigate its antigenicity to trigger inflammation, is one clinical strategy under investigation. The article is about the utility of one endopeptidase isolated from Aspergillus niger. We critique findings of this clinical trial and also summarize endopeptidase-based as well as other strategies and how they can complement gluten-free diet in the management of celiac disease.

Foetal gluten immunogenic peptides during pregnancy: a new determinant on the coeliac exposome.

BACKGROUND: The increasing incidence of coeliac disease is leading to a growing interest in active search for associated factors, even the intrauterine and early life. The exposome approach to disease encompasses a life course perspective from conception onwards has recently been highlighted. Knowledge of early exposure to gluten immunogenic peptides (GIP) in utero could challenge the chronology of early prenatal tolerance or inflammation, rather than after the infant's solid diet after birth. METHODS: We developed an accurate and specific immunoassay to detect GIP in amniotic fluid (AF) and studied their accumulates, excretion dynamics and foetal exposure resulting from AF swallowing. One hundred twenty-five pregnant women with different gluten diets and gestational ages were recruited. RESULTS: GIP were detectable in AF from at least the 16th gestational week in gluten-consuming women. Although no significant differences in GIP levels were observed during gestation, amniotic GIP late pregnancy was not altered by maternal fasting, suggesting closed-loop entailing foetal swallowing of GIP-containing AF and subsequent excretion via the foetal kidneys. CONCLUSIONS: The study shows evidence, for the first time, of the foetal exposure to gluten immunogenic peptides and establishes a positive correlation with maternal gluten intake. The results obtained point to a novel physiological concept as they describe a plausible closed-loop circuit entailing foetal swallowing of GIP contained in AF and its subsequent excretion through the foetal kidneys. The study adds important new information to understanding the coeliac exposome.

Aspergillus niger prolyl endopeptidase in celiac disease.

We comment here on the article by Stefanolo et al entitled "Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet", published in the World Journal of Gastroenterology. Celiac disease is a well-recognized systemic autoimmune disorder. In genetically susceptible people, the most evident damage is located in the small intestine, and is caused and worsened by the ingestion of gluten. For that reason, celiac patients adopt a gluten-free diet (GFD), but it has some limitations, and it does not prevent re-exposure to gluten. Research aims to develop adjuvant therapies, and one of the most studied alternatives is supplementation with Aspergillus niger prolyl endopeptidase protease (AN-PEP), which is able to degrade gluten in the stomach, reducing its concentration in the small intestine. The study found a high adherence to the GFD, but did not address AN-PEP as a gluten immunogenic peptide reducer, as it was only tested in patients following a GFD and not in gluten-exposing conditions. This study opens up new research perspectives in this area and shows that further study is needed to clarify the points that are still in doubt.

Glutenin from the Ancient Wheat Progenitor Is Intrinsically Allergenic as It Can Clinically Sensitize Mice for Systemic Anaphylaxis by Activating Th2 Immune Pathway.

Wheat allergy is a major type of food allergy with the potential for life-threatening anaphylactic reactions. Common wheat, Triticum aestivum (hexaploid, AABBDD genome), was developed using tetraploid wheat (AABB genome) and the ancient diploid wheat progenitor (DD genome)-Aegilops tauschii. The potential allergenicity of gluten from ancient diploid wheat is unknown. In this study, using a novel adjuvant-free gluten allergy mouse model, we tested the hypothesis that the glutenin extract from this ancient wheat progenitor will be intrinsically allergenic in this model. The ancient wheat was grown, and wheat berries were used to extract the glutenin for testing. A plant protein-free colony of Balb/c mice was established and used in this study. The intrinsic allergic sensitization potential of the glutenin was determined by measuring IgE response upon transdermal exposure without the use of an adjuvant. Clinical sensitization for eliciting systemic anaphylaxis (SA) was determined by quantifying the hypothermic shock response (HSR) and the mucosal mast cell response (MMCR) upon intraperitoneal injection. Glutenin extract elicited a robust and specific IgE response. Life-threatening SA associated and a significant MMCR were induced by the glutenin challenge. Furthermore, proteomic analysis of the spleen tissue revealed evidence of in vivo Th2 pathway activation. In addition, using a recently published fold-change analysis method, several immune markers positively and negatively associated with SA were identified. These results demonstrate for the first time that the glutenin from the ancient wheat progenitor is intrinsically allergenic, as it has the capacity to elicit clinical sensitization for anaphylaxis via activation of the Th2 pathway in vivo in mice.

Gluten Ataxia and mGluR1 Autoimmune Encephalitis Presenting as Acute Cerebellar Ataxia: A Case Report.

A Caucasian male in his 60s presented with acute onset of dizziness, dysarthria, and gait ataxia. Upon extensive workup, positive findings were cerebrospinal fluid (CSF) showing lymphocytic pleocytosis with oligoclonal bands, positive celiac disease autoantibodies in blood, a duodenal biopsy indicating lymphocytic infiltration, and positive anti-mGluR1 antibody titers in CSF. The patient was started on a strict gluten-free diet and intravenous immunoglobulin therapy for 5 days and showed mild consecutive improvements each day of treatment. He was discharged after 22 days, and was encouraged to continue gluten adherence, physical and speech therapy, and follow up with neuroimmunology. This report demonstrates that autoimmune encephalitis due to anti-mGluR1antibodies and gluten ataxia are both immune-mediated disorders that should be considered in acute cerebellar ataxia cases. By broadening the differential diagnosis and a comprehensive CSF analysis, identification of gluten ataxia and autoimmune encephalitis were beneficial in the management of this particular patient.

Development of pea protein nanoparticle/hydrolyzed rice glutelin fibril emulsion gels for encapsulation of curcumin.

The potential of using emulsion gels stabilized by binary plant protein nanoparticle mixtures for the encapsulation and delivery of lipophilic nutraceuticals was evaluated. The particle characteristics, physical stability, water diffusivity, microrheology, large amplitude oscillating shear (LAOS) properties, and in vitro digestion of emulsion gels prepared by different ratios of hydrolyzed rice glutelin fibrils (HRGFs) and pea protein nanoparticle (PNP) were characterized. The emulsion gel with P/H = 2:1 (0.84 µm) exhibited the best storage stability and freeze-thaw stability, as seen by the smaller oil droplet size (1.02 and 1.42 µm, respectively). Low-field pulsed NMR indicated that the majority of water in samples was highly mobile. All the samples were predominantly elastic-like materials. The P/H 2:1 emulsion gel had the lowest FI value (6.21 × 10-4 Hz), the highest MVI value (5.57 s/nm2), G'/ G″ values and enclosed area, showing that it had denser 3D network structures, higher stiffness values, and a high sensitivity to changes in strain. Additionally, P/H 2:1 emulsion gel had a relatively high lipid digestibility (96.1 %), curcumin bioaccessibility (58.9 %), and curcumin stability (94.2 %). This study showed that emulsion gels stabilized by binary protein nanoparticle mixtures (PNP/HRGF) have potential as edible delivery systems for lipophilic nutraceuticals.

Effects of konjac glucomannan with different degrees of deacetylation on the properties and structure of wheat gluten protein.

The properties and structure of gluten protein with different deacetylation degrees of konjac glucomannan (KGM) were investigated, in an attempt to improve the quality of gluten protein in flour products. Results showed that deacetylated KGM (DKGM) could improve the textural properties and enhance the thermal stability of gluten protein. DKGM increased the water holding capacity and shortened the T2 relaxation time of gluten after removing some acetyl groups. As the deacetylation degree increased, the hardness and adhesiveness of gluten gels gradually increased, while the springiness decreased. In addition, the presence of DKGM promoted the conversion from free sulfhydryl to disulfide bonds and increased the ß-sheet content in gluten protein. The low-deacetylation KGM decreased the surface hydrophobicity and fluorescence intensity of gluten protein, and the microstructures of gluten gels became more compact. Compared with gluten protein-KGM complex gel, the degradation temperature of gluten protein-DKGM complex gels was observed to increase by >3 °C. Overall, the low-deacetylation KGM was beneficial for improving the physicochemical properties and maintaining the network structure of gluten protein. This study provides valuable references and practical insights to improve gluten quality in the flour industry.

High freeze-thaw stability of Pickering emulsion stabilized by SPI-maltose particles and its effect on frozen dough.

Pickering emulsions with good freeze-thaw stability are essential in frozen food applications. This study developed a high freeze-thaw stabilized soy protein isolate (SPI)-maltose (M) Pickering emulsion and applied it to frozen doughs to investigate and reveal its impacts on the processing properties of the frozen dough. The results showed that after the freeze-thaw cycle, with a volume ratio of 1:2 of SPI to M, the appropriate amount of M changed the structure of SPI. This resulted in the Pickering emulsion prepared by the SPI exhibiting the least droplet coalescence and the best freeze-thaw stability. The results of dough rheological properties, textural properties, and binding capacity with water demonstrated that Pickering emulsions effectively inhibited the loss of gluten protein network structure in the dough after freeze treatment and increased the binding capacity of gluten proteins with starch and water in the dough. The best results were obtained with the incorporation of 3 % SPI-M high freeze-thaw stability, where the amount of bound water following three freeze-thaw cycles was 4.27 times higher than in doughs without Pickering emulsion. Overall, this study is significant for enhancing the freeze-thaw stability of Pickering emulsions stabilized by proteins and providing a new application route for Pickering emulsions.

γδ+ T-Cells Is a Useful Biomarker for the Differential Diagnosis between Celiac Disease and Non-Celiac Gluten Sensitivity in Patients under Gluten Free Diet.

BACKGROUND: The differential diagnosis between patients with celiac disease (CD) and non-celiac gluten sensitivity (NCGS) is difficult when a gluten-free diet (GFD) has been initiated before the diagnostic work-up. Isolated increases in TCRγδ+ and celiac lymphogram (increased TCRγδ+ plus decreased CD3-) may enable differential diagnosis in this challenging clinical setting. This study evaluated: (1) the accuracy of %TCRγδ+ and celiac lymphogram for diagnosing CD before and after GFD and for differentiation with NCGS; (2) TCRγδ+ kinetics at baseline and after starting GFD in both CD and NCGS. METHODS: The inclusion criteria were patients with CD (n = 104), NCGS (n = 37), and healthy volunteers (n = 18). An intestinal biopsy for intraepithelial lymphogram by flow cytometry was performed at baseline and after GFD. The optimal cutoff for CD diagnostic accuracy was established by maximizing the Youden index and via logistic regression. RESULTS: %TCRγδ+ showed better diagnostic accuracy than celiac lymphogram for identifying CD before and after GFD initiation. With a cutoff > 13.31, the accuracy for diagnosing CD in patients under GFD was 0.88 [0.80-0.93], whereas the accuracy for diagnosing NCGS (%TCRγδ+ ≤ 13.31) was 0.84 [0.76-0.89]. The percentage of TCRγδ+ cells showed differential kinetics between CD (baseline 22.7% [IQR, 16.4-33.6] vs. after GFD 26.4% [IQR, 17.8-36.8]; p = 0.026) and NCGS (baseline 9.4% [IQR, 4.1-14.6] vs. after GFD 6.4% [IQR, 3.2-11]; p = 0.022). CONCLUSION: TCRγδ+ T cell assessment accurately diagnoses CD before and after a GFD. Increased TCRγδ+ was maintained in the long term after GFD in CD but not in NCGS. Altogether, this suggests the potential usefulness of this marker for the differential diagnosis of these two entities in patients on a GFD.

Structural and mechanistic analysis of Ca2+-dependent regulation of transglutaminase 2 activity using a Ca2+-bound intermediate state.

Mammalian transglutaminases, a family of Ca2+-dependent proteins, are implicated in a variety of diseases. For example, celiac disease (CeD) is an autoimmune disorder whose pathogenesis requires transglutaminase 2 (TG2) to deamidate select glutamine residues in diet-derived gluten peptides. Deamidation involves the formation of transient γ-glutamyl thioester intermediates. Recent studies have revealed that in addition to the deamidated gluten peptides themselves, their corresponding thioester intermediates are also pathogenically relevant. A mechanistic understanding of this relevance is hindered by the absence of any structure of Ca2+-bound TG2. We report the X-ray crystallographic structure of human TG2 bound to an inhibitory gluten peptidomimetic and two Ca2+ ions in sites previously designated as S1 and S3. Together with additional structure-guided experiments, this structure provides a mechanistic explanation for how S1 regulates formation of an inhibitory disulfide bond in TG2, while also establishing that S3 is essential for γ-glutamyl thioester formation. Furthermore, our crystallographic findings and associated analyses have revealed that i) two interacting residues, H305 and E363, play a critical role in resolving the thioester intermediate into an isopeptide bond (transamidation) but not in thioester hydrolysis (deamidation); and ii) residues N333 and K176 stabilize preferred TG2 substrates and inhibitors via hydrogen bonding to nonreactive backbone atoms. Overall, the intermediate-state conformer of TG2 reported here represents a superior model to previously characterized conformers for both transition states of the TG2-catalyzed reaction.

Transfer of celiac disease-associated immunogenic gluten peptides in breast milk: variability in kinetics of secretion.

Background: Exposure to antigens is crucial for child immune system development, aiding disease prevention and promoting infant health. Some common food antigen proteins are found in human breast milk. However, it is unclear whether gluten antigens linked to celiac disease (CD) are transmitted through breast milk, potentially impacting the development of the infant's immune system. Objective: This study aimed to analyze the passage of gluten immunogenic peptides (GIP) into human breast milk. We evaluated the dynamics of GIP secretion after lactating mothers adopted a controlled gluten-rich diet. Methods: We prospectively enrolled 96 non-CD and 23 CD lactating mothers, assessing total proteins and casein in breast milk, and GIP levels in breast milk and urine. Subsequently, a longitudinal study was conducted in a subgroup of 12 non-CD lactating mothers who adopted a controlled gluten-rich diet. GIP levels in breast milk and urine samples were assayed by multiple sample collections over 96 hours. Results: Analysis of a single sample revealed that 24% of non-CD lactating mothers on a regular unrestricted diet tested positive for GIP in breast milk, and 90% tested positive in urine, with significantly lower concentrations in breast milk. Nevertheless, on a controlled gluten-rich diet and the collection of multiple samples, GIP were detected in 75% and 100% of non-CD participants in breast milk and urine, respectively. The transfer dynamics in breast milk samples were long-enduring and GIP secretion persisted from 0 to 72 h. In contrast, GIP secretion in urine samples was limited to the first 24 h, with inter-individual variations. In the cohort of CD mothers, 82.6% and 87% tested negative for GIP in breast milk and urine, respectively. Conclusions: This study definitively established the presence of GIP in breast milk, with substantial inter-individual variations in secretion dynamics. Our findings provide insights into distinct GIP kinetics observed in sequentially collected breast milk and urine samples, suggesting differential gluten metabolism patterns depending on the organ or system involved. Future research is essential to understand whether GIP functions as sensitizing or tolerogenic agents in the immune system of breastfed infants.

A human autoimmune organoid model reveals IL-7 function in coeliac disease.

In vitro models of autoimmunity are constrained by an inability to culture affected epithelium alongside the complex tissue-resident immune microenvironment. Coeliac disease (CeD) is an autoimmune disease in which dietary gluten-derived peptides bind to the major histocompatibility complex (MHC) class II human leukocyte antigen molecules (HLA)-DQ2 or HLA-DQ8 to initiate immune-mediated duodenal mucosal injury1-4. Here, we generated air-liquid interface (ALI) duodenal organoids from intact fragments of endoscopic biopsies that preserve epithelium alongside native mesenchyme and tissue-resident immune cells as a unit without requiring reconstitution. The immune diversity of ALI organoids spanned T cells, B and plasma cells, natural killer (NK) cells and myeloid cells, with extensive T-cell and B-cell receptor repertoires. HLA-DQ2.5-restricted gluten peptides selectively instigated epithelial destruction in HLA-DQ2.5-expressing organoids derived from CeD patients, and this was antagonized by blocking MHC-II or NKG2C/D. Gluten epitopes stimulated a CeD organoid immune network response in lymphoid and myeloid subsets alongside anti-transglutaminase 2 (TG2) autoantibody production. Functional studies in CeD organoids revealed that interleukin-7 (IL-7) is a gluten-inducible pathogenic modulator that regulates CD8+ T-cell NKG2C/D expression and is necessary and sufficient for epithelial destruction. Furthermore, endogenous IL-7 was markedly upregulated in patient biopsies from active CeD compared with remission disease from gluten-free diets, predominantly in lamina propria mesenchyme. By preserving the epithelium alongside diverse immune populations, this human in vitro CeD model recapitulates gluten-dependent pathology, enables mechanistic investigation and establishes a proof of principle for the organoid modelling of autoimmunity.

Characterization of a near isogenic barley line with high grain ß-amylase activity reveals a separation in the tight co-regulation of B-hordeins (Hor2) with endosperm-specific ß-amylase (Bmy1).

GSHO 2096 is a near isogenic barley line with extremely high grain ß-amylase activity, a desirable trait in the malting and brewing industry. High levels of grain ß-amylase activity are caused by a surge in endosperm-specific ß-amylase (Bmy1) gene expression during the early stages of grain development with high expression levels persisting throughout development. Origins of the high ß-amylase activity trait are perplexing considering GSHO 2096 is not supposed to have grain ß-amylase activity. GSHO 2096 is reported to be derived from a Bowman x Risø 1508 cross followed by recurrent backcrossing to Bowman (BC5). Risø 1508 carries a mutated form of the barley prolamin binding factor, which is responsible for Bmy1 expression during grain development. Thus, the pedigree of GSHO 2096 was explored to determine the potential origins of the high grain ß-amylase trait. Genotyping using the barley 50k iSelect SNP array revealed Bowman and GSHO 2096 were very similar (95.4 %) and provided evidence that both Risø 56 and 1508 are in the pedigree. Risø mutants 56 and 1508 both have perturbed hordein gene expression leading to a discernable pattern using SDS-PAGE. GSHO 2096 and Risø 56 have the same hordein pattern whereas Bowman and Risø 1508 have unique patterns. RNAseq revealed that Hor2 (B-hordein) gene expression was completely downregulated making it unique as the only known line with Bmy1 expression without Hor2 co-expression. Regardless of pedigree, GSHO 2096 remains an extremely valuable high ß-amylase activity line with potential utilization in breeding for malt quality.

Insight into the mechanism of the aggregation behavior of wheat protein modulated by l-lysine under microwave irradiation.

This study explored the mechanism of l-lysine intervention in wheat gluten protein (WG) gel formation under a microwave (MW) field. The results showed that the MW treatment had higher ζ-potential values at the same heating rate. After adding l-lysine, the solution conductivity and dielectric loss were significantly increased. Moreover, the WG gel strength enhanced 4.40% under the MW treatment. The Fourier spectra showed that the α-helix content was decreased 13.78% with the addition of lysine. The ultraviolet absorption spectra and fluorescence spectra indicated that MW irradiation impacted the interactions between WG molecules more effectively than the water bath heating, promoting the denaturation and unfolding of the protein structure. In addition, scanning electron microscopy analysis showed that the incorporation of lysine promoted an ordered network structure formation of the protein, which enhanced the gel properties. This indicated that the zwitterion of l-lysine played a regulatory role in the aggregation of proteins in the MW field.

Exploring community succession and metabolic changes in corn gluten meal-bran mixed wastes during fermentation.

Addressing the challenge of sustainable agricultural processing waste management is crucial. Protein sources are essential for livestock farming, and one viable solution is the microbial fermentation of agricultural by-products. In this study, the microorganisms utilized for fermentation were Pichia fermentans PFZS and Limmosilactobacillus fermentum LFZS. The results demonstrated that the fermented corn gluten meal-bran mixture (FCBM) effectively degraded high molecular weight proteins, resulting in increases of approximately 23.3%, 367.6%, and 159.3% in crude protein (CP), trichloroacetic acid-soluble protein (TCA-SP), and free amino acid (FAA), respectively. Additionally, there was a significant enhancement in the content of beneficial metabolites, including total phenols, carotenoids, and microorganisms. FCBM also effectively reduced anti-nutritional factors while boosting antioxidant and anti-inflammatory substances, such as dipeptides and tripeptides. The fermentation process was marked by an increase in beneficial endophytes, which was closely correlated with the enhancement of beneficial metabolites. Overall, FCBM provides a theoretical basis for substituting traditional protein resources in animal husbandry.

Molecular changes and interactions of wheat flour biopolymers during bread-making: Implications to upcycle bread waste into bioplastics.

This study aims to understand the molecular and supramolecular transformations of wheat endosperm biopolymers during bread-making, and their implications to fabricate self-standing films from stale white bread. A reduction in the Mw of amylopectin (51.8 × 106 vs 425.1 × 106 g/mol) and water extractable arabinoxylans WEAX (1.79 × 105 vs 7.63 × 105 g/mol), and a decrease in amylose length (245 vs 748 glucose units) was observed after bread-baking. The chain length distribution of amylopectin and the arabinose-to-xylose (A/X) ratio of WEAX remained unaffected during bread-making, suggesting that heat- or/and shear-induced chain scission is the mechanism responsible for molecular fragmentation. Bread-making also resulted in more insoluble cell wall residue, featured by water unextractable arabinoxylan of lower A/X and Mw, along with the formation of a gluten network. Flexible and transparent films with good light-blocking performance (<30 % transmittance) and DPPH-radical scavenging capacity (~8.5 %) were successfully developed from bread and flour. Bread films exhibited lower hygroscopicity, tensile strength (2.7 vs 8.5 MPa) and elastic modulus (67 vs 501 MPa) than flour films, while having a 6-fold higher elongation at break (10.0 vs 61.2 %). This study provides insights into the changes in wheat biopolymers during bread-making and sets a precedent for using stale bread as composite polymeric materials.