Chemical composition and health effects of Tartary buckwheat

Differential volatile compounds between rice and tartary buckwheat by solid-state fermentation with Monascus purpureus

The fermentation substrate influenced the quality and flavor of solid-state fermented products. Monascus purpureus solid-state fermentation was carried out with rice, tartary buckwheat (TB), and a combination of both (RTB) as fermentation substrates to explore the enrichment of functional components, the changes in the odor and volatile flavor components in Monascus fermented products. The fermentation process led to a decrease in starch content while increasing protein content and enriching the functional components in the final products. Additionally, Monascus pigments and monacolin K were produced during Monascus solid-state fermented rice (MSFR), TB (MSFTB) and RTB (MSFRTB). The fermentation of different raw materials resulted in variations in the composition of volatile flavor compounds (VFCs) in the fermented products. Compared to MSFR or MSFTB alone, MSFRTB could significantly increase the content of five VFCs, including nitrogen oxide, broad methane, sulfur organic, broad alcohol, and sulfur-chlor. The content of most VFCs in MSFRTB significantly increased compared to MSFR and MSFTB samples. Notably, VFCs such as 1-propanol, 2-methylpropanal, acetone, and ethanol were identified as the main flavor substances in MSFRTB. M. purpureus solid-state fermentation could enhance the nutritional composition, functional properties, and flavor quality of fermented products when compared to raw materials. The selection of fermentation raw materials significantly impacted the overall characteristics of the fermented products.

Advancements in multi-omics for nutraceutical enhancement and traits improvement in buckwheat

Buckwheat (Fagopyrum spp.) is a typical pseudocereal, valued for its extensive nutraceutical potential as well as its centuries-old cultivation. Tartary buckwheat and common buckwheat have been used globally and become well-known nutritious foods due to their high quantities of: proteins, flavonoids, and minerals. Moreover, its increasing demand makes it critical to improve nutraceutical, traits and yield. In this review, bioactive compounds accumulated in buckwheat were comprehensively evaluated according to their chemical structure, properties, and physiological function. Biosynthetic pathways of flavonoids, phenolic acids, and fagopyrin were methodically summarized, with the regulation of flavonoid biosynthesis. Although there are classic synthesis pathways presented in the previous research, the metabolic flow of how these certain compounds are being synthesized in buckwheat still remains uncovered. The functional genes involved in the biosynthesis of flavonols, stress response, and plant development were identified based on multi-omics research. Furthermore, it delves into the applications of multi-omics in improving buckwheat's agronomic traits, including: yield, nutritional content, stress resilience, and bioactive compounds biosynthesis. While pangenomics combined with other omics to mine elite genes, the regulatory network and mechanism of specific agronomic traits and biosynthetic of bioactive components, and developing a more efficient genetic transformation system for genetic engineering require further investigation for the execution of breeding designs aimed at enhancing desirable traits in buckwheat. This critical review will provide a comprehensive understanding of multi-omics for nutraceutical enhancement and traits improvement in buckwheat.

Genome-wide association study reveals of a FtS1Fa1 gene regulating rutin biosynthesis in Tartary buckwheat

Tartary buckwheat (Fagopyrum tataricum Gaertn, TB) is an annual multigrain crop belonging to the genus Fagopyrum within the Polygonaceae family. TB is valued for its balanced nutrient composition and high flavonoid content, particularly rutin, which possesses various health and medicinal benefits. Therefore, rutin has become a critical trait in determining the quality of TB. The rutin content (RC) of 101 natural TB materials measured in this study ranged from 14.08 to 24.50 mg/g, with an average value of 19.46 mg/g. This result revealed substantial natural variation in RC within the TB population. Furthermore, 314,166 high-quality single nucleotide polymorphisms (SNPs) were identified through whole-genome resequencing. Population structure analysis demonstrated that genetic information was consistent among the samples, while significant structural differences were observed among the groups. A genome-wide association study (GWAS) employing a mixed linear model (MLM) identified the SNP site Ft4:1777524 as significantly associated with rutin levels. Within the 400 kb candidate region, 27 key genes were identified. Further joint analysis of previous transcriptome data revealed that FtS1Fa1 is closely linked to RC. Molecular biological characterization revealed that this gene belongs to the S1Fa-like family, is localized in chloroplasts, but lacks transcriptional activation capabilities. Functional studies indicated that FtS1Fa1 can promote rutin accumulation in TB by upregulating the expression of the rutin biosynthesis gene. In conclusion, this study enhances the understanding of the regulatory mechanisms governing rutin biosynthesis in TB and provides important germplasm resources for the molecular breeding of high-rutin TB varieties.

Serendipita indica-dominated synthetic microbial consortia enhanced tartary buckwheat growth and improved its tolerance to drought stress

The cultivation of tartary buckwheat serves dual roles, offering health benefits and nutritional advantages. Nonetheless, its cultivation is challenged by issues such as soil degradation and climatic drought. Plant growth-promoting (PGP) microorganisms hold promise for addressing these challenges. In this study, we investigated the effects of Serendipita indica inoculation on the root-associated microbial communities of tartary buckwheat. Additionally, we used S. indica to construct synthetic microbial consortia, and their role in promoting the growth and enhancing the drought resistance of tartary buckwheat was evaluated. This study found that the colonization of S. indica in tartary buckwheat promoted the enrichment of beneficial microorganisms such as Actinobacteriota, Sphingomonas, and Mortierella, while reducing the relative abundance of pathogenic genera including Cladosporium, Alternaria, and Acremonium. In addition, the inoculation of the microbial consortia significantly promoted the photosynthesis and biomass accumulation of tartary buckwheat, while also improving soil structure and fertility. Under drought conditions, introducing microbial groups markedly boosted root development, lowered the density of stomata and rate of transpiration in tartary buckwheat leaves, and decreased H2O2 and Malondialdehyde (MDA) levels, thus greatly enhancing tartary buckwheat's resistance to drought. In conclusion, our findings demonstrated that the microbial consortia constructed with S. indica can significantly promote the growth of tartary buckwheat and enhance its drought resistance. However, the specific molecular mechanisms underlying these effects require further investigation in future studies. These findings will provide important theoretical support for the development of novel microbial fertilizers.

Formation mechanism of polyphenol-Tartary buckwheat starch complexes and their Pickering emulsifying capacity

The complexes of gallic acid (GA), epigallocatechin-3-gallate (EGCG) and tannic acid (TA) with Tartary buckwheat starch (TBS) were prepared using the autoclaving method, and the effects of polyphenol structure on the bound polyphenol amount and the Pickering emulsifying ability of the complexes were evaluated. The molecular structure and size of polyphenols determine their different binding modes and binding amounts with TBS. The semi embedded (partially exposed) binding modes of EGCG have a positive impact on the binding amount and emulsifying capacity. The complexation altered the morphology and crystalline structure of TBS. Molecular docking analysis confirmed that the binding mode of polyphenols to starch significantly influenced the emulsifying capacity of the complexes. EGCG-TBS complexes with contact angle of 90.88° demonstrated optimal efficacy in reducing oil-water interfacial tension. It could stabilize Pickering emulsions with the oil phase volume fractions (φ) of 50 % and 60 % when the concentration (c) was 3.0 %. GA-TBS was difficult to construct stable Pickering emulsions, due to the fully embedded binding mode that is unable to alter the surface hydrophobicity of TBS. While TA-TBS could only stabilize the Pickering emulsions with φ = 50 % and 60 % at c = 4.0 %, due to the lowest binding amount and the inferior emulsifying capacity to TBS. Therefore, the difference in complex structure and binding mode affects the emulsifying performance of Pickering emulsions, which contribute to improve the emulsification theory of polyphenols and proteins.

Enhancing physio biochemical traits and yield of common buckwheat Fagopyrum esculentum with rice husk biochar and nano iron oxide under water stress

Climate change is making droughts more frequent, which is a major problem for crop yield, especially for crops that are vulnerable to drought, such as common buckwheat (Fagopyrum esculentum). Drought stress affects negatively on physiological and biochemical processes of plants, leading to reduced yields. This study addresses the knowledge gap regarding effective strategies to mitigate drought-induced damage and enhance productivity in buckwheat. We hypothesized that iron oxide nanoparticles (Fe3O4 NPs) and rice husk biochar could improve drought tolerance in buckwheat by modulating its physiological and biochemical responses. To test this, buckwheat plants were grown under well-watered (80% of field capacity, FC) and drought (40% of FC) conditions following a completely randomized design (CRD) with three replications. Results showed that the application of 50 g/kg rice husk biochar and 400 ppm Fe3O4 NPs, either separately or in combination, significantly enhanced the yield and improved key physiological and biochemical traits, including relative water content, photosynthetic rate, stomatal conductance, chlorophyll content, and antioxidant activity. The combination of Fe3O4 NPs and rice husk biochar led to improvements the plants' relative water content, photosynthetic rate, chlorophyll levels, membrane stability index, proline, antioxidant activity (DPPH), and seed yield by 22.37, 17.11, 43.05, 16.07, 43.75, 8.59, and 50.87%, respectively compared to untreated drought plants. Moreover, this treatment reduced oxidative stress indicators such as hydrogen peroxide and malondialdehyde by 31.09 and 38.19%, respectively. These results show that Fe3O4 NPs, when combined with rice husk biochar, significantly improve drought tolerance in common buckwheat, providing a viable strategy to increase crop yields in water-limited environments. In view of climate change, this study emphasises the potential of combining biochar with nanomaterials for sustainable agricultural practices.

High moisture extrusion induced interaction of Tartary buckwheat protein and starch mitigating the in vitro starch digestion

This study investigated the effects of adding 4-20 % Tartary buckwheat protein (TBP, with a purity of 93.35 %) on the structural, thermal, and digestive properties of Tartary buckwheat starch (TBS) by high moisture (60 %) extrusion. The added TBP embedded and enwrapped the starch matrix, which formed protein-starch complexes. After adding 4 %-20 % TBP, the shear degradation of AP decreased. Conversely, the shear degradation of AM chains increased. The addition of TBP promoted the retrogradation of starch in extrudates, enhancing their short- and long-range ordered structures. Compared with extruded TBS, extrudates contained TBP showed a reduction of gelatinization enthalpy, a high content of resistant starch, and a lower starch digestibility. These findings provided an insight into the protein-starch interactions under high moisture extrusion, which would promote the advancement of starch-based foods with high TBP content.

Effects of different adzuki bean flour additions on structural and functional characteristics of extruded buckwheat noodles

BACKGROUND

Understanding the effects of different additions of adzuki bean flour (ABF) on structural and functional characteristics of extruded buckwheat noodles is important in developing high-quality starchy foods with desirable glycemic indexes. This study explored how varying amounts of ABF in extruded buckwheat noodles influenced their structural and functional characteristics.

RESULTS

The findings indicated that adding ABF substantially boosted the levels of protein and flavonoids, while decreasing the content of fat and starch. Adding ABF to the noodles extended the optimum cooking time and led to a reduction in both the stickiness of the cooked noodles and the pore size of the starch gel structure, compared with pure buckwheat noodles. Fourier transform infrared spectroscopy indicated that R1047/1022 increased with the content of ABF increased, while R1022/995 decreased. X-ray diffraction showed that the relative crystallinity of buckwheat noodles was enhanced with increasing ABF amount. Adding ABF notably significantly decreased the estimated glycemic index. The buckwheat noodles extruded with 20% ABF addition demonstrated notably stronger α-glucosidase inhibitory effects than those extruded with no ABF addition.

CONCLUSION

The present study demonstrates that the additions of ABF improved the structure and hypoglycemic activity of extruded buckwheat noodles while decreasing starch digestibility, and the optimal value was reached at an ABF addition of 20%. The study might fill gaps in starch noodle research and provide a new strategy for the development of functional food in the food industry. © 2024 Society of Chemical Industry.

Removal of proteins and lipids affects structure, in vitro digestion and physicochemical properties of rice flour modified by heat-moisture treatment

BACKGROUND

The objective of this experiment was to investigate the role of endogenous proteins and lipids in the structural and physicochemical properties of starch in heat-moisture treatment (HMT) rice flour and to reveal their effect on starch digestibility under heat.

RESULTS

The findings indicate that, in the absence of endogenous proteins and lipids acting as a physical barrier, especially proteins, the interaction between rice flour and endogenous proteins and lipids diminished. This reduction led to fewer starch-protein inclusion complexes and starch-lipid complexes, altering the granule aggregation structure of rice flour. It resulted in a decrease in particle size, an increase in agglomeration between starch granules, and more surface cracking on rice granules. Under HMT conditions with a moisture content of 30%, slight gelatinization of the starch granules occurred, contributing to an increased starch hydrolysis rate. In addition, the elevated thermal energy effect of HMT enhanced interactions between starch molecular chains. These resulted in a decrease in crystallinity, short-range ordering, and the content of double-helix structure within starch granules. These structural transformations led to higher pasting temperatures, improved hot and cold paste stability, and a decrease in peak viscosity, breakdown, setback, and enthalpy of pasting of the starch granules.

CONCLUSION

The combined analysis of microstructure, physicochemical properties, and in vitro digestion characteristics has enabled us to further enhance our understanding of the interaction mechanisms between endogenous proteins, lipids, and starches during HMT. © 2024 Society of Chemical Industry.

Identification of the Granule-Bound Starch Synthase (GBSS) Genes Involved in Amylose Biosynthesis in Tartary Buckwheat (Fagopyrum tataricum (L.) Gaertn.)

Tartary buckwheat is a nutrient-rich pseudo-cereal whose starch contents, including amylose and amylopectin contents, and their properties hold significant importance for enhancing yield and quality. The granule-bound starch synthase (GBSS) is a key enzyme responsible for the synthesis of amylose, directly determining the amylose content and amylose-to-amylopectin ratio in crops. Although one has already been cloned, the GBSS genes at the genome-wide level have not yet been fully assessed and thoroughly analyzed in Tartary buckwheat. This study comprehensively analyzed the FtGBSSs in Tartary buckwheat. Based on the genome data of Tartary buckwheat, five FtGBSS genes, namely FtGBSS-1 to FtGBSS-5, were identified on three chromosomes, exhibiting about 1800 bp lengths in their CDSs and numerous exons and introns in gene structures. Amino acid analyses revealed high homology in ten GBSS proteins from Tartary buckwheat, rice, maize, and Arabidopsis thaliana, with a specific starch synthase catalytic domain and ten conserved motifs. The Tartary buckwheat GBSS proteins had a closer relationship with GBSS proteins from monocot based on evolutionary relationship analysis. Expression analyses suggested that the FtGBSS genes showed distinct tissue-specific expression patterns in Tartary buckwheat and rice-Tartary buckwheat. Among them, FtGBSS-1, FtGBSS-2, and FtGBSS-4 were higher expressed in the root, stem, or flower, suggesting that they have a role in the amylose synthesis of these tissues. Notably, FtGBSS-3 and FtGBSS-5 were more highly expressed in seeds than in other tissues, suggesting that they have a pivotal role in amylose synthesis of the seeds of Tartary buckwheat. Furthermore, the cis acting elements in the promoters of FtGBSSs and their binding transcription factors (TFs) were investigated. A protein-protein interaction network was constructed and co-expression was analyzed based on the gene expression patterns of the FtGBSSs, and the identified TFs, belonging to bZIP, ERF, bHLH, and MADS-box TF families, were identified within this network, and their expression patterns were significantly correlated to the expression patterns of two seed-specific FtGBSS genes (FtGBSS-3 and FtGBSS-5). Finally, FtGBSS1-5 was successfully transformed into rice through transgenic manipulation, and the FtGBSS1-5 overexpression lines showed an increase in amylose content accompanied by a reduction in amylopectin and total starch contents compared with WT. Overall, this research not only deepens our understanding of the molecular mechanisms of amylose synthesis in Tartary buckwheat, but also provides scientific insights for enhancing crop amylose content and quality through molecular breeding.

Analysis of the MYB gene family in tartary buckwheat and functional investigation of FtPinG0005108900.01 in response to drought

Tartary buckwheat (Fagopyrum tataricum) is an important crop used for edible food and medicinal usage. Drought annually brings reduction in crop yield and quality, causing enormous economic losses. Transcription factors are often involved in the regulation of plant responses to environmental stresses. In this study, we identified 233 MYB transcription factors in tartary buckwheat and classified them into 13 groups, including 1R, R2R3, 3R, 4R types. Gene structure and conserved motifs of these 233 FtMYBs suggested the relative conservation of these FtMYBs within each group. There is strong collinearity within the genomes of F. tataricum, with identifying syntenic gene pairs of FtMYB. Further, the expansion of FtMYB genes was attributed to whole genome duplication. The enrichment analysis of cis-acting elements in the FtMYB genes indicated that FtMYBs may participate in abiotic stress responses. The transcriptional changes of FtMYB genes in tartary buckwheat were then investigated using public data and qPCR. A number of FtMYB genes exhibited apparent transcript levels in the detected tissues and most of them disturbed their expression after the treatment of PEG6000 or natural treatment of tartary buckwheat seedlings. Some of the FtMYB genes showed a similar expression trend with qPCR validation. FtMYB gene FtPinG0005108900.01 were shown to activated by PEG6000 and natural drought treatment, and its encoded protein localizes to nucleus, revealing it as a typical transcription factor. Overexpression of FtPinG0005108900.01 increase the drought tolerance, and transcriptome analysis indicated that lignin synthesis other than flavonoid biosynthesis pathway was activated in the overexpressing plants following drought treatment. Our results provided detailed evolution and comparative genomic information of FtMYBs in tartary buckwheat and dissected the function of a FtMYB gene FtPinG0005108900.01 in response to drought.

Mechanism of hydrocolloids effect on buckwheat starch gels from interaction and structural perspectives: A comparative study

Controlling the digestibility and gel properties of Tartary buckwheat starch (TBS) has become a central issue for functional foods. The effects of hydroxypropyl methylcellulose (HPMC), guar gum (GG) and Konjac glucomannan (KGM) on TBS from the interaction and structural perspectives were studied. Three hydrocolloids increased the peak, trough and final viscosity of TBS in a concentration-dependent manner. Dynamic frequency sweeps and flow state tests indicated that the TBS-hydrocolloid systems exhibited gel-like behaviour, and TBS-HPMC was more thixotropic than the other systems. The addition of hydrocolloids significantly enhanced the hardness and chewiness of the TBS gels. The structural analyses revealed that hydrocolloids did not affect the functional groups or crystalline structure of TBS, but did improve the orderliness of the systems. The interaction mechanism confirmed that hydrogen bonds and electrostatic forces are the main forces in the formation of HPMC and TBS-KGM gels; while hydrogen bonds are dominant in TBS-GG gels. Moreover, HPMC, GG and KGM can each delay starch hydrolysis to some extent, with a hydrolysis rate varying from 78.66 % ± 2.81 % to 44.8 % ± 0.35 % at three addition levels. The results can provide both theoretical and practical insights into the glycaemic control of starch and TBS-based jelly foods production.

Identification of Fungus GZ in Buckwheat Rhizosphere and Its Promoting Effect in Buckwheat Seed Germination

To obtain fungal strains that enhance plant growth in the rhizosphere soil of buckwheat, we utilized morphological and molecular biological methods to identify 10 fungal strains from the rhizosphere soil and subsequently evaluated their effects on seed germination. The results demonstrated that all 10 fungal strains were classified as Isaria cateniannulata. The spores of these strains significantly enhanced the germination of buckwheat seeds, with germination rates improving by 3.46% to 700.75% compared to the control group. This study fills the gap in understanding I. cateniannulata as soil rhizosphere fungi, providing a foundation and materials for the seed coating technology of buckwheat seeds.

Chemical constituents and biological activities of endophytic fungi from Fagopyrum dibotrys

Background

Fagopyrum dibotrys is an important wild food and feed germplasm resource. It has high nutritional and medicinal value and is rich in natural products, including flavonoids, phenolic acids, coumarins, and alkaloids. Endophytic fungi in F. dibotrys have emerged as valuable sources of natural products. However, studies on the biological activity and chemical composition of these endophytic fungi remain limited.

Methods

In this paper, a new method to obtain natural active ingredients by fermentation of endophytic fungi from medicinal plants was proposed. Then the antioxidant and pathogenic activities of the endophytic fungi extracts were determined in vitro. In addition, secondary metabolites produced by endophytic fungi with medicinal activity were analyzed by high performance liquid chromatography-tandem mass spectrometry (LC-MS).

Results

Among the 95 endophytic fungal strains in F. dibotrys, four strains with high phenol yields were selected by reaction: Alternaria alstroemeriae (J2), Fusarium oxysporum (J15), Colletotrichum karsti (J74), and Colletotrichum boninense (J61). Compared with those of various extracts, the ethyl acetate fractions of A. alstroemeriae (J2), F. oxysporum (J15), and C. boninense (J61) exhibited superior antioxidant and antibacterial properties. The results indicated that the fungal extract was an excellent natural antioxidant and might be a potential antibacterial agent. The DPPH free radical clearance of A. alstroemeriae was 94.96 ± 0.004%. These findings indicated that A. alstroemeriae had strong antioxidant activity. In addition, the extract of A. alstroemeriae had good antibacterial activity against Escherichia coli and Staphylococcus aureus, with MICs of 0.5 and 0.05 mg/mL, respectively. The chemical constituents of the ethyl acetate extract from A. alstroemeriae were further analyzed by liquid chromatography-mass spectrometry (LC-MS). We noted that A. alstroemeriae can create a variety of medicinal substances that have high value in medicine, such as caffeic acid (884.75 ng/mL), 3-phenyllactic acid (240.72 ng/mL) and norlichexanthone (74.36 ng/mL).

Discussion

In summary, many valuable active substances and medicinal substances can be obtained through the study of endophytic fungi of F. dibotrys.

Preparation and Pharmacokinetics of Brain-Targeted Nanoliposome Loaded with Rutin

Rutin is a flavonoid compound with potential for treating Alzheimer's disease, preventing brain damage, mitigating cerebral ischemia-reperfusion injury, and exhibiting anti-glioblastoma activity. However, its efficacy is limited by its low solubility, poor bioavailability, and limited permeability across the blood-brain barrier (BBB). To enhance the bioavailability and brain-targeting ability of Rutin, transferrin-modified Rutin liposome (Tf-Rutin-Lip) was developed using liposomes as a delivery system. Rutin liposomes were prepared using the thin-film dispersion method, and the preparation conditions were optimized using the response surface methodology. Then, transferrin (Tf) was incorporated into the liposomes through covalent modification, yielding Tf-Rutin liposomes. The toxicity of these liposomes on bEnd.3 cells, as well as their impact on the tight junctions of these cells, was rigorously evaluated. Additionally, in vitro and in vivo experiments were conducted to validate the brain-targeting efficacy of the Tf-Rutin liposomes. A susceptible detection method was developed to characterize the pharmacokinetics of Tf-Rutin-Lip further. The optimized conditions for the preparation of Tf-Rutin-Lip were determined as follows: a lipid-to-cholesterol ratio of 4.63:1, a drug-to-lipid ratio of 1:45.84, a preparation temperature of 42.7 °C, a hydration volume of 20 mL, a sonication time of 10 min, a surfactant concentration of 80 mg/mL, a DSPE-MPEG-2000 concentration of 5%, and a DSPE-PEG2000-COOH to DSPE-MPEG-2000 molar ratio of 10%. The liposomes did not affect the cell activity of bEnd.3 cells at 24 h and did not disrupt the tight junction of the blood-brain barrier. Tf-modified liposomes were taken up by bEnd.3 cells, which, in turn, passed through the BBB, thus improving liposomal brain targeting. Furthermore, the results of pharmacokinetic experiments showed that the Cmax, AUC0-∞, AUC0-t, MRT0-∞, and t1/2 of Tf-Rutin-Lip increased 1.99-fold, 2.77-fold, 2.58-fold, 1.26-fold, and 1.19-fold compared to those of free Rutin solution, respectively. These findings suggest that Tf-Rutin-Lip is brain-targeted and may enhance the efficacy of Rutin in the treatment of brain disorders.

Plant anthraquinones: Classification, distribution, biosynthesis, and regulation

Anthraquinones are polycyclic compounds with an unsaturated diketone structure (quinoid moiety). As important secondary metabolites of plants, anthraquinones play an important role in the response of many biological processes and environmental factors. Anthraquinones are common in the human diet and have a variety of biological activities including anticancer, antibacterial, and antioxidant activities that reduce disease risk. The biological activity of anthraquinones depends on the substitution pattern of their hydroxyl groups on the anthraquinone ring structure. However, there is still a lack of systematic summary on the distribution, classification, and biosynthesis of plant anthraquinones. Therefore, this paper systematically reviews the research progress of the distribution, classification, biosynthesis, and regulation of plant anthraquinones. Additionally, we discuss future opportunities in anthraquinone research, including biotechnology, therapeutic products, and dietary anthraquinones.

The effect of exogenous gibberellin and its synthesis inhibitor treatments for morphological and physiological characteristics of Tartary buckwheat

Gibberellin (GA3) is an important plant hormone involved in many physiological and developmental processes in plants. However, the physiological mechanism of GA3 on the regulation yield and grain shell thickness of Tartary buckwheat is still unclear. In this study, the thick-shelled cultivar "Jinqiao 2" and thin-shelled cultivar "Miku 18" were used to study the effects of different concentrations (0, 50, and 100 mg L-1) of exogenous GA3 and chlorocholine chloride (CCC, GA3 synthesis inhibitor) on the cellulose content, amylase, and sucrose synthase (SS) activity in grain shell and the yield of Tartary buckwheat. The application of exogenous GA3 can improve the cellulose content and the activity of amylase and SS in the grain shell of the two Tartary buckwheat varieties. It can also increase the main stem node number, main stem branch number, grains per plant, and yield. Compared with the control treatment (CK, 0 mg L-1), the 100 mg/L exogenous GA3 treatment increased the number of grains per plant, grain weight per plant, 1000-grain weight, and yield of Jinqiao 2 by 20.1%, 41.9%, 13%, and 34.7%, respectively. These items of Miku 18 were increased by 26%, 15.2%, 10.2%, and 23.8%. The application of CCC reduced the activity of amylase and SS and cellulose content in grain shell. In addition, it decreased the main stem node number, main stem branch number, grains per plant, and yield of Tartary buckwheat. In summary, exogenous GA3 treatment not only improved the yield of Tartary buckwheat but also increased the thickness of grain shell by enhancing the activity of amylase and SS and promoting the synthesis and accumulation of cellulose. The results can provide theoretical references for clarifying the physiological mechanism of the difference in shell thickness between Tartary buckwheat varieties.

QTL Mapping and Candidate Gene Analysis for Starch-Related Traits in Tartary Buckwheat (Fagopyrum tataricum (L.) Gaertn)

Starch is the main component that determines the yield and quality of Tartary buckwheat. As a quantitative trait, using quantitative trait locus (QTL) mapping to excavate genes associated with starch-related traits is crucial for understanding the genetic mechanisms involved in starch synthesis and molecular breeding of Tartary buckwheat varieties with high-quality starch. Employing a recombinant inbred line population as research material, this study used QTL mapping to investigate the amylose, amylopectin, and total starch contents across four distinct environments. The results identified a total of 20 QTLs spanning six chromosomes, which explained 4.07% to 14.41% of the phenotypic variation. One major QTL cluster containing three stable QTLs governing both amylose and amylopectin content, qClu-4-1, was identified and located in the physical interval of 39.85-43.34 Mbp on chromosome Ft4. Within this cluster, we predicted 239 candidate genes and analyzed their SNP/InDel mutations, expression patterns, and enriched KEGG pathways. Ultimately, five key candidate genes, namely FtPinG0004897100.01, FtPinG0002636200.01, FtPinG0009329200.01, FtPinG0007371600.01, and FtPinG0005109900.01, were highlighted, which are potentially involved in starch synthesis and regulation, paving the way for further investigative studies. This study, for the first time, utilized QTL mapping to detect major QTLs controlling amylose, amylopectin, and total starch contents in Tartary buckwheat. The QTLs and candidate genes would provide valuable insights into the genetic mechanisms underlying starch synthesis and improving starch-related traits of Tartary buckwheat.

LC-MS and MALDI-MSI-based metabolomic approaches provide insights into the spatial-temporal metabolite profiles of Tartary buckwheat achene development

Tartary buckwheat, celebrated as the "king of grains" for its flavonoid and phenolic acid richness, has health-promoting properties. Despite significant morphological and metabolic variations in mature achenes, research on their developmental process is limited. Utilizing Liquid chromatography-mass spectrometry and atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry imaging, we conducted spatial-temporal metabolomics on two cultivars during achene development. Metabolic profiles including 17 phenolic acids and 83 flavonoids are influenced by both varietal distinctions and developmental intricacies. Notably, flavonols, as major flavonoids, accumulated with achene ripening and showed a tissue-specific distribution. Specifically, flavonol glycosides and aglycones concentrated in the embryo, while methylated flavonols and procyanidins in the hull. Black achenes at the green achene stage have higher bioactive compounds and enhanced antioxidant capacity. These findings provide insights into spatial and temporal characteristics of metabolites in Tartary buckwheat achenes and serve as a theoretical guide for selecting optimal resources for food production.

Contemporary Speculations and Insightful Thoughts on Buckwheat-A Functional Pseudocereal as a Smart Biologically Active Supplement

Today, food scientists are interested in more rational use of crops that possess desirable nutritional properties, and buckwheat is one of the functional pseudocereals that represents a rich source of bioactive compounds (BACs) and nutrients, phytochemicals, antimicrobial (AM) agents and antioxidants (AOs), which can be effectively applied in the prevention of malnutrition and celiac disease and treatment of various important health problems. There is ample evidence of the high potential of buckwheat consumption in various forms (food, dietary supplements, home remedies or alone, or in synergy with pharmaceutical drugs) with concrete benefits for human health. Contamination as well as other side-effects of all the aforementioned forms for application in different ways in humans must be seriously considered. This review paper presents an overview of the most important recent research related to buckwheat bioactive compounds (BACs), highlighting their various functions and proven positive effects on human health.

Effects of Different Pretreatments on Hot Air Drying Characteristics, Nutrition, and Antioxidant Capacity of Tartary Buckwheat Sprouts

In order to enhance the quality of hot air drying for Tartary buckwheat sprouts and minimize the loss of active substances, this research explored the impact of Color Protection(CP), Osmosis(OM), Blanching (BC), β-cyclodextrin (β-CD), and Ultrasound (US) in conjunction with hot air drying on the color, nutritional value, antioxidant properties, and other attributes of Tartary buckwheat sprouts. The findings revealed that as the drying temperature increased from 50 °C to 70 °C, the drying duration for Tartary buckwheat sprouts decreased across all treatment groups, leading to a higher dehydration rate. Treatments involving CP, US, and BC effectively reduced the drying time of Tartary buckwheat sprouts. Sprouts subjected to CP, β-CD, and US treatments exhibited elevated L* values and decreased a* values and displayed a more vibrant green color. When exposed to a hot air setting of 60 °C, the total flavonoid content in the CP, OM, β-CD, and US groups increased by 8.76%, 6.76%, 12.34%, and 4.25%, respectively, compared to the Control Group (CK). The application of the CP, OM, β-CD, and US treatments enhanced the sprouts' ability to combat ABTS and DPPH free radicals. Notably, under hot air conditions of 60 °C, the β-CD treatment demonstrated the most effective quality preservation during the hot air drying process for sprouts. This study provides valuable insights into the drying behavior of Tartary buckwheat sprouts and offers guidance for optimizing the drying procedures in industrial settings. Tartary buckwheat sprouts contain a variety of polyphenols and have a high water content. The study of changes in active components such as polyphenols and their alteration mechanisms in Tartary buckwheat sprouts under different processing methods is particularly important for the development of sprout processing.

Buckwheat OMICS: present status and future prospects

Buckwheat (Fagopyrum spp.) is an underutilized resilient crop of North Western Himalayas belonging to the family Polygonaceae and is a source of essential nutrients and therapeutics. Common Buckwheat and Tatary Buckwheat are the two main cultivated species used as food. It is the only grain crop possessing rutin, an important metabolite with high nutraceutical potential. Due to its inherent tolerance to various biotic and abiotic stresses and a short life cycle, Buckwheat has been proposed as a model crop plant. Nutritional security is one of the major concerns, breeding for a nutrient-dense crop such as Buckwheat will provide a sustainable solution. Efforts toward improving Buckwheat for nutrition and yield are limited due to the lack of available: genetic resources, genomics, transcriptomics and metabolomics. In order to harness the agricultural importance of Buckwheat, an integrated breeding and OMICS platforms needs to be established that can pave the way for a better understanding of crop biology and developing commercial varieties. This, coupled with the availability of the genome sequences of both Buckwheat species in the public domain, should facilitate the identification of alleles/QTLs and candidate genes. There is a need to further our understanding of the molecular basis of the genetic regulation that controls various economically important traits. The present review focuses on: the food and nutritional importance of Buckwheat, its various omics resources, utilization of omics approaches in understanding Buckwheat biology and, finally, how an integrated platform of breeding and omics will help in developing commercially high yielding nutrient rich cultivars in Buckwheat.

From 'Farm to Fork': Exploring the Potential of Nutrient-Rich and Stress-Resilient Emergent Crops for Sustainable and Healthy Food in the Mediterranean Region in the Face of Climate Change Challenges

In the dynamic landscape of agriculture and food science, incorporating emergent crops appears as a pioneering solution for diversifying agriculture, unlocking possibilities for sustainable cultivation and nutritional bolstering food security, and creating economic prospects amid evolving environmental and market conditions with positive impacts on human health. This review explores the potential of utilizing emergent crops in Mediterranean environments under current climate scenarios, emphasizing the manifold benefits of agricultural and food system diversification and assessing the impact of environmental factors on their quality and consumer health. Through a deep exploration of the resilience, nutritional value, and health impacts of neglected and underutilized species (NUS) such as quinoa, amaranth, chia, moringa, buckwheat, millet, teff, hemp, or desert truffles, their capacity to thrive in the changing Mediterranean climate is highlighted, offering novel opportunities for agriculture and functional food development. By analysing how promoting agricultural diversification can enhance food system adaptability to evolving environmental conditions, fostering sustainability and resilience, we discuss recent findings that underscore the main benefits and limitations of these crops from agricultural, food science, and health perspectives, all crucial for responsible and sustainable adoption. Thus, by using a sustainable and holistic approach, this revision analyses how the integration of NUS crops into Mediterranean agrifood systems can enhance agriculture resilience and food quality addressing environmental, nutritional, biomedical, economic, and cultural dimensions, thereby mitigating the risks associated with monoculture practices and bolstering local economies and livelihoods under new climate scenarios.

Analysis of characteristic aromas of buckwheat with different germplasm using gas chromatography-mass spectrometry combined with chemometrics and multivariate statistical analysis

In this study, the volatile components in 40 samples of Tartary buckwheat and common buckwheat from 6 major producing areas in China were analyzed. A total of 77 volatile substances were identified, among which aldehydes and hydrocarbons were the main volatile components. Odor activity value analysis revealed 26 aromatic compounds, with aldehydes making a significant contribution to the aroma of buckwheat. Seven key compounds that could be used to distinguish Tartary buckwheat from common buckwheat were identified. The orthogonal partial least squares-discriminant analysis was effectively used to classify Tartary buckwheat and common buckwheat from different producing areas. This study provides valuable information for evaluating buckwheat quality, breeding high-quality varieties, and enhancing rational resource development.

Fagopyrins from Buckwheat Flowers: Structural and Stereochemical Characterization Through Combined NMR/CD Spectroscopy and Theoretical Calculations

Fagopyrins are phenantroperylenequinones present in the flowers of Fagopyrum esculentum (buckwheat) endowed with photodynamic activity. It has been reported that fagopyrin extracts actually contain a complex mixture of closely related compounds, differing only on the nature of the perylenequinone substituents. We report our systematic and detailed study on the chemical composition of fagopyrin extracts by a combination of preparative and analytical techniques. The combined use of 1H-NMR and CD spectroscopy was found to be particularly suited to fully characterize all stereochemical aspects of the extracted fagopyrins. For the first time nine isomers have been structurally characterized and their stereochemistry fully elucidated. The presence of two different heterocyclic ring substituents, two stereogenic centers and the inherent axial chirality of the aromatic system provides a complex stereochemical relationships among isomers, thus giving account of the high level of molecular multiplicity found in the extract.

Regulatory Module FtMYB5/6-FtGBF1-FtUFGT163 Promotes Rutin Biosynthesis in Tartary Buckwheat

Tartary buckwheat is highly valued for its abundant rutin (quercetin 3-O-rutinoside). As a flavonoid glycoside, rutin is synthesized with the crucial involvement of UDP-dependent glycosyltransferases (UGTs). However, the functions and transcriptional regulation of the UGT-encoded genes remain poorly understood. This study identified a key gene, FtUFGT163, potentially encoding flavonol 3-O-glucoside (1 → 6) rhamnosyltransferase in Tartary buckwheat through omics analysis and molecular docking methods. The recombinant FtUFGT163 expressed in Escherichia coli demonstrated the capacity to glycosylate isoquercetin into rutin. Overexpression of FtUFGT163 significantly enhanced the rutin content in Tartary buckwheat. Further investigation identified a novel bZIP transcription factor, FtGBF1, that enhances FtUFGT163 expression by binding to the G-box element within its promoter, thereby augmenting rutin biosynthesis. Additional molecular biology experiments indicated that the specific positive regulator of rutin, FtMYB5/6, could directly activate the FtGBF1 promoter. Collectively, this study elucidates a novel regulatory module, termed "FtMYB5/6-FtGBF1-FtUFGT163", which effectively coordinates the biosynthesis of rutin in Tartary buckwheat, offering insights into the genetic enhancement of nutraceutical components in crops.

Impacts of ultrasound-assisted Fenton degradation and alkaline de-esterification on structural properties and biological effects of pectic polysaccharides from Tartary buckwheat leaves

Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn) leaf has abundant rhamnogalacturonan-I enriched pectic polysaccharides, which exert various health-promoting effects. Nevertheless, the potential relationship between the chemical structure and the biological function of pectic polysaccharides from Tartary buckwheat leaves (TBP) remains unclear. Therefore, to bridge the gap between the chemical structure and the biological function of TBP, the impacts of ultrasound-assisted Fenton degradation (UFD) and mild alkaline de-esterification (MAD) on structural properties and biological effects of TBP were systematically studied. Compared with the native TBP (molecular mass, 9.537 × 104 Da), the molecular masses of degraded TBPs (TBP-MMW, 4.811 × 104 Da; TBP-LMW, 2.101 × 104 Da) were significantly reduced by the UFD modification, while their primary chemical structures were overall stable. Besides, compared with the native TBP (esterification degree, 22.73 %), the esterification degrees of de-esterified TBPs (TBP-MDE, 14.27 %; TBP-LDE, 6.59 %) were notably reduced by the MAD modification, while their primary chemical structures were also overall stable. Furthermore, the results revealed that both UFD and MAD modifications could significantly improve the antioxidant, antiglycation, and immunostimulatory effects of TBP. Indeed, TBP's biological effects were negatively correlated to its molecular mass and esterification degree, while positively linked to its free uronic acids. The findings demonstrate that both UFD and MAD modifications are promising techniques for the structural modification of TBP, which can remarkedly promote its biological effects. Besides, the present results are conducive to better understanding TBP's structure-bioactivity relationship.

Enhancing rutin accumulation in Tartary buckwheat through a novel flavonoid transporter protein FtABCC2

Tartary buckwheat (Fagopyrum tataricum) is an annual coarse cereal from the Polygonaceae family, known for its high content of flavonoid compounds, particularly rutin. But so far, the mechanisms of the flavonoid transport and storage in Tartary buckwheat (TB) remain largely unexplored. This study focuses on ATP-binding cassette transporters subfamily C (ABCC) members, which are crucial for the biosynthesis and transport of flavonoids in plants. The evolutionary and expression pattern analyses of the ABCC genes in TB identified an ABCC protein gene, FtABCC2, that is highly correlated with rutin synthesis. Subcellular localization analysis revealed that FtABCC2 protein is specifically localized to the vacuole membrane. Heterologous expression of FtABCC2 in Saccharomyces cerevisiae confirmed that its transport ability of flavonoid glycosides such as rutin and isoquercetin, but not the aglycones such as quercetin and dihydroquercetin. Overexpression of FtABCC2 in TB hairy root lines resulted in a significant increase in total flavonoid and rutin content (P < 0.01). Analysis of the FtABCC2 promoter revealed potential cis-acting elements responsive to hormones, cold stress, mechanical injury and light stress. Overall, this study demonstrates that FtABCC2 can efficiently facilitate the transport of rutin into vacuoles, thereby enhancing flavonoids accumulation. These findings suggest that FtABCC2 is a promising candidate for molecular-assisted breeding aimed at developing high-flavonoid TB varieties.

The Effect of Acid Hydrolysis on the Pickering Emulsifying Capacity of Tartary Buckwheat Flour

The effect of sulfuric acid hydrolysis on the Pickering emulsifying capacity of Tartary buckwheat flour (TBF) rich in starch was evaluated for the first time. The results indicate that the sulfuric acid concentration and hydrolysis time had a significant impact on the Pickering emulsifying capacity of acid-hydrolyzed Tartary buckwheat flour (HTBF). A low sulfuric acid concentration (1-2 mol/L) could reduce the particle size of HTBF, but it also decreased the Pickering emulsifying ability. At a sulfuric acid concentration of 3 mol/L, appropriate treatment time (2 and 3 days) led to particle aggregation but significantly improved wettability, thereby resulting in a rapid enhancement in emulsifying capacity. Under these conditions, the obtained HTBF (HTBF-D2-C3 and HTBF-D3-C3) could stabilize medium-chain triglyceride (MCT)-based Pickering high-internal-phase emulsions (HIPEs) with an oil-phase volume fraction of 80% at the addition amounts (c) of ≥1.0% and ≥1.5%, respectively. Its performance was significantly superior to that of TBF (c ≥ 2.0%). Furthermore, at the same addition amount, the droplet size of HIPEs constructed by HTBF-D3-C3 was smaller than that of HTBF-D2-C3, and its gel strength and microrheological performance were also superior to those of HTBF-D2-C3, which was attributed to the higher wettability of HTBF-D3-C3. The findings of this study can facilitate the in-depth application of Tartary buckwheat and provide references for the development of novel Pickering emulsifiers.

Strigolactones affect the yield of Tartary buckwheat by regulating endogenous hormone levels

BACKGROUND

As a newly class of endogenous phytohormones, strigolactones (SLs) regulate crop growth and yield formation by interacting with other hormones. However, the physiological mechanism of SLs affect the yield by regulating the balance of endogenous hormones of Tartary buckwheat is still unclear.

RESULTS

In this study, a 2-year field experiment was conducted on Tartary buckwheat (Jinqiao 2) to study the effects of different concentrations (0, 10, and 20 µmol/L) of artificial synthetic analogs of SLs (rac-GR24) and inhibitor of SL synthesis (Tis-108) on the growth, endogenous-hormone content, and yield of Tartary buckwheat. The main-stem branch number, grain number per plant, grain weight per plant, and yield of Tartary buckwheat continuously decreased with increased rac-GR24 concentration, whereas the main-stem diameter and plant height initially increased and then decreased. Rac-GR24 treatment significantly increased the content of SLs and abscisic acid (ABA) in grains, and it decreased the content of Zeatin (Z) + Zeatin nucleoside (ZR). Conversely, Tis-108 treatment decreased the content of SLs and ABA but increased the content of Z + ZR. Results of correlation analysis showed that the content of ABA and SLs, the ratio of SLs/(Z + ZR), SLs/ABA, and ABA/(Z + ZR) were significantly negatively correlated with the yield of Tartary buckwheat, and that Z + ZR content was significantly positively correlated with the yield. Regression analysis further showed that ABA/ (Z + ZR) can explain 58.4% of the variation in yield.

CONCLUSIONS

In summary, by adjusting the level of endogenous SLs in Tartary buckwheat, the balance of endogenous hormones in grains can be changed, thereby exerting the effect on yield. The results can provide a new agronomic method for the high-yield cultivation of Tartary buckwheat.

Platforms of graphene/MXene heterostructure for electrochemical monitoring of rutin in drug and Tartary buckwheat tea

The use of two-dimensional heterostructure composite as electrode modification material has become a new strategy to improve the electrocatalytic activity and electroactive sites of electrochemical sensor. Herein, a soluble heterostructure, namely rGO-PSS@MXene, was designed and synthesized by integrating poly (sodium p-styrenesulfonate)-functionalized reduced graphene oxide into MXene nanosheets via ultrasonic method. The interactive heterostructure can effectively alleviate the self-stacking of MXene and rGO, endowing them with superior electron transfer capacity and large specific surface area, thereby producing prominent synergistic electrocatalytic effect towards rutin. In addition, the excellent enrichment effect of rGO-PSS@MXene for rutin also plays an important role through the electrostatic and π-π stacking interactions. The electrochemical characteristics of rutin on the sensor were examined in detail and a sensitive sensing method was proposed. Under optimized conditions, the method showed satisfactory linear relationship for rutin in the concentration range of 0.005-10.0 μM, with limit of detection of 1.8 nM (S/N = 3). The quantitative validation results in herbal medicine and commercial Tartary buckwheat tea were highly consistent with the labeled quantity and the results of HPLC determination, respectively, suggesting the sensor possessed excellent selectivity and accuracy. This proposed strategy for rutin determination is expected to expand the application of MXene heterostructure in electrochemical sensors, and is envisioned as a promising candidate for quality monitoring of drugs and foods.

The diversity of endophytic fungi in Tartary buckwheat (Fagopyrum tataricum) and its correlation with flavonoids and phenotypic traits

Tartary buckwheat (Fagopyrum tataricum) is a significant medicinal crop, with flavonoids serving as a crucial measure of its quality. Presently, the artificial cultivation of Tartary buckwheat yields low results, and the quality varies across different origins. Therefore, it is imperative to identify an effective method to enhance the yield and quality of buckwheat. Endophytic fungi reside within plants and form a mutually beneficial symbiotic relationship, aiding plants in nutrient absorption, promoting host growth, and improving secondary metabolites akin to the host. In this study, high-throughput sequencing technology was employed to assess the diversity of endophytic fungi in Tartary buckwheat. Subsequently, a correlation analysis was performed between fungi and metabolites, revealing potential increases in flavonoid content due to endophytic fungi such as Bipolaris, Hymenula, and Colletotrichum. Additionally, a correlation analysis between fungi and phenotypic traits unveiled the potential influence of endophytic fungi such as Bipolaris, Buckleyzyma, and Trichosporon on the phenotypic traits of Tartary buckwheat. Notably, the endophytic fungi of the Bipolaris genus exhibited the potential to elevate the content of Tartary buckwheat metabolites and enhance crop growth. Consequently, this study successfully identified the resources of endophytic fungi in Tartary buckwheat, explored potential functional endophytic fungi, and laid a scientific foundation for future implementation of biological fertilizers in improving the quality and growth of Tartary buckwheat.

Effect of Pleurotus eryngii mycelial fermentation on the composition and antioxidant properties of tartary buckwheat

In this study, we investigated the effect of solid-state fermentation of Pleurotus eryngii on the composition and antioxidant activity of Tartary buckwheat (TB). Firstly, the solid-state fermentation of P. eryngii mycelium with buckwheat was carried out, and the fermentation process was explored. The results of the extraction process and method selection experiments showed that the percolation extraction method was superior to the other two methods. The results of extraction rate, active components and antioxidant activity measurements before and after fermentation of TB extract showed that the extraction rate increased about 1.7 times after fermentation. Total flavonoids, rutin and triterpene contents were increased after fermentation compared to control. Meanwhile, LC-MS results showed an increase in the content of the most important substances in the fermented TB extract and the incorporation of new components, such as oleanolic acid, ursolic acid, amino acids, and D-chiral inositol. The fermented TB extract showed stronger antioxidant activity, while the protein and amino acid contents increased by 1.93-fold and 1.94-fold, respectively. This research was the first to use P. eryngii to ferment TB and prepared a lyophilized powder that could be used directly using vacuum freeze-drying technology. Not only the use of solid-state fermentation technology advantages of edible fungi to achieve value-added buckwheat, but also to broaden the scope of TB applications. This study will provide ideas and directions for the development and application of edible mushroom fermentation technology and TB.

Genomic insight into the origin, domestication, dispersal, diversification and human selection of Tartary buckwheat

BACKGROUND

Tartary buckwheat, Fagopyrum tataricum, is a pseudocereal crop with worldwide distribution and high nutritional value. However, the origin and domestication history of this crop remain to be elucidated.

RESULTS

Here, by analyzing the population genomics of 567 accessions collected worldwide and reviewing historical documents, we find that Tartary buckwheat originated in the Himalayan region and then spread southwest possibly along with the migration of the Yi people, a minority in Southwestern China that has a long history of planting Tartary buckwheat. Along with the expansion of the Mongol Empire, Tartary buckwheat dispersed to Europe and ultimately to the rest of the world. The different natural growth environments resulted in adaptation, especially significant differences in salt tolerance between northern and southern Chinese Tartary buckwheat populations. By scanning for selective sweeps and using a genome-wide association study, we identify genes responsible for Tartary buckwheat domestication and differentiation, which we then experimentally validate. Comparative genomics and QTL analysis further shed light on the genetic foundation of the easily dehulled trait in a particular variety that was artificially selected by the Wa people, a minority group in Southwestern China known for cultivating Tartary buckwheat specifically for steaming as a staple food to prevent lysine deficiency.

CONCLUSIONS

This study provides both comprehensive insights into the origin and domestication of, and a foundation for molecular breeding for, Tartary buckwheat.

Tartary buckwheat protein-phenol conjugate prepared by alkaline-based environment: Identification of covalent binding sites of phenols and alterations in protein structural and functional characteristics

Tartary buckwheat protein-rutin/quercetin covalent complex was synthesized in alkaline oxygen-containing environment, and its binding sites, conformational changes and functional properties were evaluated by multispectral technique and proteomics. The determination of total sulfhydryl and free amino groups showed that rutin/quercetin can form a covalent complex with BPI and could significantly reduce the group content. Ultraviolet-visible spectrum analysis showed that protein could form new characteristic peaks after binding with rutin/quercetin. Circular dichroism spectrum analysis showed that rutin and quercetin caused similar changes in the secondary structure of proteins, both promoting β-sheet to α-helix, β-ture and random coil transformation. The fluorescence spectrometry results showed that the combination of phenols can cause the fluorescence quenching, and the combination of rutin was stronger than the quercetin. Proteomics showed that there were multiple covalent binding sites between phenols and protein. Rutin had a high affinity for arginine, and quercetin and cysteine had high affinity. Meanwhile, the combination of rutin/quercetin and protein had reduced the surface hydrophobic ability of the protein, and improved the foaming, stability and antioxidant properties of the protein. This study expounded the mechanism of the combination of BPI and rutin/quercetin, and analysed the differences of the combination of protein and phenols in different structures. The findings can provide a theoretical basis for the development of complexes in the area of food.

Fagopyrum tataricum (L.) Gaertn interacts with Gsk-3β/Nrf-2 signalling to protect neurotoxicity in a zebrafish model

ETHNOPHARMACOLOGICAL RELEVANCE

Fagopyrum tataricum (L.) Gaertn is used as a folk medicine in many Asian countries due to its anti-inflammatory, antioxidant, and several other health-promoting properties. It is also prescribed to improve neurocognitive functions and alleviate inflammatory conditions.

AIM OF THE STUDY

Oxidative stress and neuroinflammation plays a crucial role in neurodegenerative conditions. Hence, based on the ethnomedical claims and available literature, the present study investigated neuroprotective efficacy of a seed extract (ft-ext) of Fagopyrum tataricum against acrylamide (ACR)-induced neurotoxicity.

MATERIALS AND METHODS

The phytochemical characterization of ft-ext was performed by a high-performance liquid chromatography method. Molecular interactions of the identified compounds of ft-ext were studied using an in-silico docking tool. An in-vitro protein denaturation assay was done to check anti-inflammatory activity. The 5 days' post-fertilized zebrafish larvae were exposed to 1 mM and 2.5 mM ACR with or without ft-ext for 72 h to study its neuroprotective efficacy. Real-time polymerase chain reaction and western blotting studies were performed to analyse the oxidative stress-related gene and protein expressions respectively.

RESULTS

The extract showed the presence of chlorogenic acid, rutin, caffeic acid, vitexin, syringic acid, quercetin, p-coumaric acid, kaempferol, and ferulic acid. In-vitro protein denaturation assay of ft-ext showed a potent anti-inflammatory effect. The ft-ext improved ACR-mediated locomotor deficit and reduced overall mortality in the larvae. The brain lipid peroxidation and protein carbonylation results revealed an elevated level of oxidative stress in the ACR-treated group, which was reduced in ft-ext-treated larvae. The extract treatment increased the expression of nrf2, gpx, and hmox1a, while simultaneously downregulated trxr2 levels in the brain of larvae exposed to ACR. The treatment also showed inactivation of Gsk-3β, thus maintaining a normal pool of Nrf2 and β-catenin. Molecular docking of identified compounds of ft-ext showed possible hydrogen and hydrophobic interactions with Gsk-3β.

CONCLUSION

The ft-ext prevents ACR-mediated neurotoxicity by suppressing Gsk-3β mediated oxidative stress.

Germplasm Resources and Metabolite Marker Screening of High-Flavonoid Tartary Buckwheat (Fagopyrum tataricum)

Tartary buckwheat is an annual minor cereal crop with a variety of secondary metabolites, endowing it with a high nutritional and medicinal value. Flavonoids constitute the primary compounds of Tartary buckwheat. Recently, metabolomics, as an adjunct breeding method, has been increasingly employed in crop research. This study explores the correlation between the total flavonoid content (TFC) and antioxidant capacity in 167 Tartary buckwheat varieties. Ten Tartary buckwheat varieties with significant differences in flavonoid content and antioxidant capacity were selected by cluster analysis. With the use of liquid chromatography-mass spectrometry, 58 flavonoid compounds were identified, namely, 42 flavonols, 10 flavanols, 3 flavanones, 1 isoflavone, 1 anthocyanidin, and 1 proanthocyanidin. Different samples were clearly separated by employing principal component analysis and partial least-squares discriminant analysis. Eight differential flavonoid compounds were further selected through volcano plots and variable importance in projection. Differential metabolites were highly correlated with TFC and antioxidant capacity. Finally, metabolic markers of kaempferol-3-O-hexoside, kaempferol-7-O-glucoside, and naringenin-O-hexoside were determined by the random forest model. The findings provide a basis for the selection and identification of Tartary buckwheat varieties with high flavonoid content and strong antioxidant activity.

Effects of extracted oil of fermented Tartary buckwheat on lipid-lowering, inflammation modulation, and gut microbial regulation in mice

This study investigated the composition of Tartary buckwheat oil fermented by Monascus purpureus and extracted under supercritical CO2 conditions (FTBO) and evaluated its effects on lipid-lowering, inflammation modulation, and gut microbial regulation in mice that were fed a high-fat diet (MOD). Compared with the raw oil (TBO), the γ-oryzanol content reached 27.09 mg g-1; the monounsaturated fatty acid (MUFA) content (such as oleic acid and palmitic acid) was elevated; and the antioxidant capacities of DPPH, ABTS, and hydroxyl were improved in FTBO (p < 0.0001). Then, supplementation with FTBO had a remarkable effect on reducing the body weight and visceral obesity as well as alleviating hyperglycemia, dyslipidemia, inflammatory reactions, and liver damage. The TC, TG, and LDL-C levels in the liver and plasma were reduced, and the HDL-C levels in the liver were increased (p < 0.05). In particular, the high-dose group (FTBOH) exhibited the most significant effect on reducing the pro-inflammatory cytokines ET, TNF-α, IL-1β, and IL-6 in the liver, which were 18.85, 570.12, 50.47, and 26.22 pg mL-1, respectively (p < 0.05). Moreover, FTBO reversed intestinal disorders and increased the intestinal microbial diversity and richness. The relative abundance of beneficial bacteria, such as Bifidobacterium, Lactobacillus, Limosilactobacillus, and Lachnospiraceae_UCG-006, were increased, and the relative abundance of the harmful bacteria Staphylococcus and Lachnoclostridium were reduced. In summary, FTBO has potential applications as a dietary supplement or dietary modifier in lowering blood lipids, modulating immune activity, and reversing intestinal disorders. This study provides reference guidance for the subsequent industrialization and development of Tartary buckwheat, the extension of the industrial chain, the development of new products, and the extraction of functional components.

Integrated multi-omic analysis reveals the cytokinin and sucrose metabolism-mediated regulation of flavone glycoside biosynthesis by MeJA exposure in Ficus pandurata Hance

Ficus pandurata Hance (FPH) holds a rich history as a traditional Chinese botanical remedy, utilized both as a culinary condiment and a medicinal intervention for diverse ailments. This study focuses on enhancing FPH's therapeutic potential by subjecting it to exogenous methyl jasmonate (MeJA) treatment, a strategy aimed at elevating the levels of active constituents to align with clinical and commercial requirements. Employing metabolomics, the impact of MeJA treatment on the lipid and flavonoid profiles of FPH leaves was investigated, revealing a marked increase in flavone glycosides, a subset of flavonoids. Investigation into the regulatory mechanism governing flavone glycoside biosynthesis uncovered elevated expression of structural genes associated with flavonoid production in response to MeJA exposure. Global endogenous hormone analysis pinpointed the selective activation of JA and cytokinin biosynthesis following MeJA treatment. Through a comprehensive integration of transcriptomic and metabolomic data, the cooperative stimulation of glucosyltransferase activity, alongside the JA and cytokinin signaling pathways, orchestrated by MeJA were explored. Furthermore, genes linked to sucrose metabolism exhibited heightened expression, concomitant with a noteworthy surge in antioxidant activity subsequent to MeJA treatment. These findings validate the augmentation of FPH leaf antioxidant capacity through MeJA intervention, while also offering profound insights into the regulatory role of MeJA in flavone glycoside biosynthesis, mediated by the interplay between cytokinin and sucrose metabolism pathways.

Ultrasonic-assisted resting of Tartary buckwheat dough: Study on its effect and mechanism

Utilizing natural hypoglycemic ingredients in staple foods is a safe and effective way to improve diabetes. High Tartary buckwheat noodles have garnered research interest due to their hypoglycemic properties. However, increasing the Tartary buckwheat content poses challenges in noodle processing and affects their edible quality. Effective resting is a critical link to improve the processing performance of noodle and edible quality of noodle. Therefore, research was conducted on ultrasound assisted resting of Tartary buckwheat dough (TBD) to explore its feasibility and mechanism in improving the quality of Tartary buckwheat noodle. The results indicated that ultrasound treatment effectively promoted the migration of weakly-bound water towards strongly-bound water, thereby enhancing the gluten protein network structure and increasing the α-helix and β-sheet contents significantly (p < 0.05). Furthermore, Texture analysis indicated decreased hardness and adhesion, and increased elasticity and stretching distance in the final noodles. Ultrasound-assisted maturation pre-treatment shortens TBD's dough's resting time and improves noodle quality, according to this study.

Effect of sodium carbonate on the properties of seventy percent of Tartary buckwheat composite flour-based doughs and noodles and the underlying mechanism

The impact of Na2 CO3 on the properties of doughs and noodles containing 70% Tartary buckwheat flour was investigated. Low-field 1 H nuclear magnetic resonance showed the mobility of water in the doughs significantly declined with the addition content of alkali from 0% to 0.9%. Na2 CO3 promoted the transformation from free sulfhydryl groups to disulfide bonds in doughs because the sulfhydryl groups in cysteine preferred to form thiolate anion and then oxidate under alkaline conditions. As for non-covalent chemical interactions, a significant increase of hydrogen bonds and a decrease of hydrophobic interactions were observed after Na2 CO3 addition. Quantitative analysis of microstructure showed that more uniform and denser gluten networks with higher branching rate and shorter average protein length and width formed in the doughs with 0.3%-0.6% of Na2 CO3 . The aggregated glutenin macropolymer and enhanced protein structure led to significantly stronger tensile of Tartary buckwheat dough sheets, which could meet the demand of continuous processing in the factory. Dough with alkali had higher swelling power and pasting viscosities, contributing to higher water absorption, and improved textural attributes of cooked noodles. This study demonstrated the possibility of adding Na2 CO3 at a moderate level for promoting the sheeting, cooking, and eating properties of high Tartary buckwheat flour composite noodles.

Tartary buckwheat protein-derived peptide AFYRW alleviates H2O2-induced vascular injury via the PI3K/AKT/NF-κB pathway

Tartary buckwheat protein-derived peptide (Ala-Phe-Tyr-Arg-Trp, AFYRW) is a natural active peptide that hampers the atherosclerosis process, but the underlying role of AFYRW in angiogenesis remains unknown. Here, we present a system-based study to evaluate the effects of AFYRW on H2O2-induced vascular injury in human umbilical vein endothelial cells (HUVECs). HUVECs were co-incubated with H2O2 for 2 h in the vascular injury model, and AFYRW was added 24 h in advance to investigate the protective mechanism of vascular injury. We identified that AFYRW inhibits oxidative stress, cell migration, cell invasion, and angiogenesis in H2O2-treated HUVECs. In addition, we found H2O2-induced upregulation of phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), phosphorylation of nuclear factor-κB (NF-κB) p65 and nuclear translocation of NF-κB decreased by AFYRW. Taken together, AFYRW attenuated H2O2-induced vascular injury through the PI3K/AKT/NF-κB pathway. Thereby, AFYRW may serve as a therapeutic option for vascular injuries.

The Effect of Leaf Plasticity on the Isolation of Apoplastic Fluid from Leaves of Tartary Buckwheat Plants Grown In Vivo and In Vitro

Vacuum infiltration-centrifugation (VIC) is the most reproducible technique for the isolation of apoplast washing fluid (AWF) from leaves, but its effectiveness depends on the infiltration-centrifugation conditions and the anatomical and physiological peculiarities of leaves. This study aimed to elaborate an optimal procedure for AWF isolation from the leaves of Tartary buckwheat grown in in vivo and in vitro conditions and reveal the leaf anatomical and physiological traits that could contribute to the effectiveness of AWF isolation. Here, it was demonstrated that leaves of buckwheat plants grown in vitro could be easier infiltrated, were less sensitive to higher forces of centrifugation (900× g and 1500× g), and produced more AWF yield and apoplastic protein content than in vivo leaves at the same forces of centrifugation (600× g and 900× g). The extensive study of the morphological, anatomical, and ultrastructural characteristics of buckwheat leaves grown in different conditions revealed that in vitro leaves exhibited significant plasticity in a number of interconnected morphological, anatomical, and physiological features, generally driven by high RH and low lighting; some of them, such as the reduced thickness and increased permeability of the cuticle of the epidermal cells, large intercellular spaces, increase in the size of stomata and in the area of stomatal pores, higher stomata index, drop in density, and area of calcium oxalate druses, are beneficial to the effectiveness of VIC. The size of stomata pores, which were almost twice as large in in vitro leaves as those in in vivo ones, was the main factor contributing to the isolation of AWF free of chlorophyll contamination. The opening of stomata pores by artificially created humid conditions reduced damage to the in vivo leaves and improved the VIC of them. For Fagopyrum species, this is the first study to develop a VIC technique for AWF isolation from leaves.

Serendipita indica Promotes the Growth of Tartary Buckwheat by Stimulating Hormone Synthesis, Metabolite Production, and Increasing Systemic Resistance

The main objective of this study was to investigate the influence of Serendipita indica on the growth of Tartary buckwheat plants. This study highlighted that the roots of Tartary buckwheat can be colonized by S. indica and that this fungal endophyte improved plants height, fresh weight, dry weight, and grain yield. In the meantime, the colonization of S. indica in Tartary buckwheat leaves resulted in elevated levels of photosynthesis, plant hormone content, antioxidant enzyme activity, proline content, chlorophyll content, soluble sugars, and protein content. Additionally, the introduction of S. indica to Tartary buckwheat roots led to a substantial rise in the levels of flavonoids and phenols found in the leaves and seeds of Tartary buckwheat. In addition, S. indica colonization reduced the content of malondialdehyde and hydrogen peroxide when compared to non-colonized plants. Importantly, the drought tolerance of Tartary buckwheat plants is increased, which benefits from physiology and bio-chemical changes in plants after S. indica colonized. In conclusion, we have shown that S. indica can improve systematic resistance and promote the growth of Tartary buckwheat by enhancing the photosynthetic capacity of Tartary buckwheat, inducing the production of IAA, increasing the content of secondary metabolites such as total phenols and total flavonoids, and improving the antioxidant enzyme activity of the plant.

Study on the reduction of Tartary buckwheat allergenicity during Pediococcus pentosaceus fermentation by HPLC-MS/MS analysis

Tartary buckwheat contains more valuable nutrients than common buckwheat, but it also contains allergenic proteins that induce allergic reactions through an IgE-mediated response. Our study demonstrated that fermentation by Pediococcus pentosaceus degrades allergenic proteins in Tartary buckwheat, as confirmed by HPLC-MS/MS analysis of polypeptides. Our results showed significant degradation of the protein after 16 h of Pediococcus pentosaceus fermentation (PP16), leading to a reduction in IgE-binding activity. Comparison with unfermented Tartary buckwheat (UTB) peptides yielded 2042 fragments, of which 756 fragments associated with allergenic proteins were upregulated. Among them, the expression of 213 fragments was reduced by 71.83%. By performing bioactivity prediction on potential allergenic peptide fragments, we identified six peptide fragments derived from Fagt 1, potentially contributing to the residual allergenicity in PP16. These suggest that Pediococcus pentosaceus fermentation can effectively destroy allergen epitopes and mitigate the allergenicity of Tartary buckwheat.

Consumers' Preferences towards Bread Characteristics Based on Food-Related Lifestyles: Insights from Slovenia

Consumers' recognition and understanding of food characteristics can have an important role when making purchase decisions. The current study analysed consumer preferences for bread, an important food in the diets of Central European countries. The study included a conjoint experiment on a representative sample of 547 adult consumers in Slovenia. The following bread attributes: functional ingredients (chia seeds, linseed, quinoa, and Tartary buckwheat); nutritional claims (low salt, high fibre, and high protein); and other claims (organic, free from additives, flour from Slovenia, and wholegrain) were studied. The results showed the strongest relative importance for functional ingredients (a mean relative importance of 83.9%). In addition, a deeper insight into consumer preference was investigated by a recently developed modular instrument for food-related lifestyles. Latent class cluster analysis (LCA) enabled the identification of four consumer segments (uninvolved, conservative, health-conscious, and moderate) with different preferences toward selected functional ingredients, nutrition, and other claims. The results provide insights that allow for a better understanding of consumer preferences for functional ingredients and claims, and new perspectives for bread marketing to different consumer segments based on food-related lifestyles. Identifying the drivers that affect bread purchasing and consumption can support reformulation activities and product promotion in the direction of reinforcing healthier food choices.

Interkingdom multi-omics analysis reveals the effects of nitrogen application on growth and rhizosphere microbial community of Tartary buckwheat

Tartary buckwheat (Fagopyrum tataricum Gaertn.) is an important pseudocereal crop with excellent edible, nutritional and medicinal values. However, the yield of Tartary buckwheat (TB) is very low due to old-fashioned cultivation techniques, particularly unreasonable application of nitrogen fertilizer. To improve the understanding on the theories of nitrogen use in TB, the effects of nitrogen application on growth, as well as chemical properties and microbial community of rhizosphere soil were investigated in this study. Nitrogen application could promote the plant height, stem diameter, nitrogen accumulation and yield of TB. The relative abundance and diversity of bacteria and fungi in the rhizosphere soil of TB were improved by nitrogen fertilizer. Nitrogen application increased the abundance of beneficial bacteria such as Lysobacter and Sphingomonas in rhizosphere soil, and decreased the abundance of pathogenic fungi such as Fusarium and Plectosphaerella. The results indicated that nitrogen application changed the distribution of microbial communities in TB rhizosphere soil. Furthermore, the specific enriched or depleted microorganisms in the rhizosphere soil of four TB varieties were analyzed at OTU level. 87 specific nitrogen-responsive genes with sequence variation were identified in four varieties by integrating genomic re-sequencing and transcriptome analysis, and these genes may involve in the recruitment of specific rhizosphere microorganisms in different TB varieties. This study provided new insights into the effects of nitrogen application on TB growth and rhizosphere microbial community, and improved the understanding on the mechanisms of TB root-microbe interactions.

Buckwheat Flour (Fagopyrum esculentum Moench)-A Contemporary View on the Problems of Its Production for Human Nutrition

Buckwheat is returning to the countries of Central Europe; there are several reasons for this: firstly, due to its interesting chemical composition (proteins, fibre, and phenolic compounds), which is reflected in its nutritional value and potential health benefits. Secondly, because buckwheat, and buckwheat flour especially, are suitable raw materials for the production of gluten-free foods. Buckwheat flours are classified similarly to wheat flours, but the different anatomy of wheat grains and buckwheat seeds makes this classification partly misleading. While wheat flours are largely produced by one standard process, the production process for buckwheat flours is more varied. For wheat and wheat flours, the basic quality parameters and their required ranges for different types of primary and secondary processing are clearly defined. This is not the case for buckwheat and buckwheat flours, and the definition of the parameters and their ranges that characterize its technological quality remain unclear. The standardization of quality parameters and production processes is likely to be necessary for the potential expansion of the use of buckwheat for food production and, in particular, for bakery products.

Antidiabetic activity of Tartary buckwheat protein-derived peptide AFYRW and its effects on protein glycosylation of pancreas in mice

Diabetes Mellitus (DM) is one of the most important public health problems, and new antidiabetic drugs with fewer side effects are urgently needed. Here, we measured the antidiabetic effects of an antioxidant peptide (Ala-Phe-Tyr-Arg-Trp, AFYRW) from Tartary Buckwheat Albumin (TBA) in a high-fat diet/streptozotocin (HFD/STZ)-induced diabetic mouse model. The data showed that AFYRW suppressed hepatocyte steatosis and triglycerides while ameliorating insulin resistance in mice. Successively, the influence of AFYRW on aberrant protein glycosylation in diabetic mice was further investigated by lectin microarrays. The results suggested AFYRW could restore the expression of GalNAc, GalNAcα1-3Gal and GalNAcα1-3Galβ1-3/4Glc recognized by PTL-I, Siaα2-3Galβ1-4Glc(NAc)/Glc, Siaα2-3Gal, Siaα2-3 and Siaα2-3GalNAc recognized by MAL-II, terminating in GalNAcα/β1-3/6Gal recognized by WFA and αGalNAc, αGal, anti-A and B recognized by GSI-I to normal levels in the pancreas of HFD-STZ-induced diabetic mice. This work may provide new targets for the future discovery of potential biomarkers to evaluate the efficacy of food-derived antidiabetic drugs based on precise alterations of glycopatterns in DM.

Buckwheat tartary regulates the Gsk-3β/β-catenin pathway to prevent neurobehavioral impairments in a rat model of surgical menopause

Menopause is a natural aging process characterized by decreased levels of sex hormones in females. Deprivation of estrogen following menopause results in alterations of dendritic arborization of the neuron that leads to neurobehavioral complications. Hormone replacement therapy is in practice to manage postmenopausal conditions but is associated with a lot of adverse effects. In the present study, the efficacy of buckwheat tartary (Fagopyrum tataricum) whole seed extract was investigated against the neurobehavioral complication in middle-aged ovariectomized rats, which mimic the clinical postmenopausal condition. Hydroalcoholic extraction (80% ethanol) was done, and quantification of major marker compounds in the extract was performed using HPLC. Oral treatment of the extract following the critical window period rescued the reconsolidation process of spatial and recognition memory, as well as depression-like behavior. Gene expression analysis disclosed elevated oxidative stress and neuroinflammation that largely disturb the integrity of the blood-brain barrier in ovariectomized rats. Gfap and Pparγ expression also showed reactive astrogliosis in the rats subjected to ovariectomy. The extract treatment reverted the elevated oxidative stress, neuroinflammation and expression of the studied genes. Furthermore, protein expression analysis revealed that Gsk-3β was activated differentially in the brain, as suggested by β-catenin protein expression, which was normalized following the treatment with extract and rescued the altered neurobehavioral process. The results of the current study concluded that Fagopyrum tataricum seed extract is better option to overcome the neurobehavioral complications associated with the menopause.