Phenolics content and antioxidant activity of tartary buckwheat from different locations

Evaluation of differences in volatile flavor compounds between liquid-state and solid-state fermented Tartary buckwheat by Monascus purpureus

The differences in volatile flavor compounds (VFCs) between Monascus-solid-state fermented Tartary buckwheat (MSFTB) and Monascus-liquid-state fermented Tartary buckwheat (MLFTB) were investigated using electronic nose and gas chromatography-ion mobility spectrometry (GC-IMS) analysis. The study revealed several significant differences in the composition and abundance of VFCs between the two states. Compared to MSFTB, MLFTB exhibited notable increases in various elements including protein, crude fat, total flavonoids, total polyphenols, Monacolin K, Monascus pigments. Principal component analysis demonstrated significant increases in the production of specific VFCs in MLFTB compared to MSFTB. A total of 25 VFCs were identified through GC-IMS, including 9 esters, 7 alcohols, 5 ketones, and 4 aldehydes. The content of pleasant VFCs in MLFTB was significantly higher than in MSFTB. These compounds served as both VFCs and key aroma components during fermentation. In conclusion, the Monascus fermentation state played a crucial role in enhancing the flavor quality of Tartary buckwheat.

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.

Tartary buckwheat rutin: Accumulation, metabolic pathways, regulation mechanisms, and biofortification strategies

Rutin is a significant flavonoid with strong antioxidant property and various therapeutic effects. It plays a crucial role in disease prevention and human health maintenance, especially in anti-inflammatory, antidiabetic, hepatoprotective and cardiovascular effects. While many plants can synthesize and accumulate rutin, tartary buckwheat is the only food crop possessing high levels of rutin. At present, the rutin content (RC) is regarded as the key index for evaluating the nutritional quality of tartary buckwheat. Consequently, rutin has become the focus for tartary buckwheat breeders and has made considerable progress. Here, we summarize research on the rutin in tartary buckwheat in the past two decades, including its accumulation, biosynthesis and breakdown pathways, and regulatory mechanisms. Furthermore, we propose several strategies to increase the RC in tartary buckwheat seeds based on current knowledge. This review aims to provide valuable references for elevating the quality of tartary buckwheat in the future.

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.

Anticancer effects of rutin from Fagopyrum tataricum (tartary buckwheat) against osteosarcoma cell line

BACKGROUND

The present study is analysisof the seeds of buckwheat (Fagopyrum sp.),member of the Polygonaceae family for isolation of rutin and its anticancer property againstOsteosarcoma celllines (SAOS2). The selected plant is traditionally used for diabetes and cancer. It has several biological properties such as antibacterial, antioxidant and anti-aging.

PURPOSE

Thirty-five buckwheat cultivars were obtained from Nepal Agriculture Genetic Resources Centre (NAGRC) Khumaltar, Kathmandu, Nepal, and Kumrek Sikkim. These plant varieties are scientifically evaluated their biological properties.

METHODS

Rutin wasfractionated from buckwheat seeds using methanol fraction and analysed for quality by HPLC method. The rutin fraction of the cultivar NGRC03731 a tartary buck wheat and standard rutin was used against Osteosarcoma cell lines (SAOS2) and human gingival fibroblast cells (hGFs) for anticancer activity. The cell viability using rutin fraction and standard rutin treated with SAOS2 cells were assessed by MTT assay. For further research, the best doses (IC-50: 20 g/ml) were applied. By using AO/EtBr dual staining, the effects of Rutin fraction on SAOS2 cell death were analysed. The scratch wound healing assay was used to analyse cell migration. Real-time PCR was used to analyse the pro-/anti-apoptotic gene expression.

RESULTS

The seeds with the highest rutin content, NGRC03731 seeds, had 433 mg/100 g of rutin.The rutin fraction treatment and standard rutin significantly reduced cell viability in the MTT assay, and osteosarcoma cells were observed on sensitive to the IC-50 dose at a concentration of 20 g/ml after 24 h.The SAOS2 cells exposed to rutin fraction at 20 g/ml and standard rutin at 10 g/ml exhibited significant morphological alterations, cell shrinkage and decreased cell density, which indicate apoptotic cells.Rutin-fraction treated cells stained with acridine orange/ethidium bromide (AO/EtBr) dual staining cells turned yellow, orange, and red which indicatesto measure apoptosis.The anti-migration potential of rutin fraction, results prevented the migration of SAOS2 cancer cells.Rutin-fraction significantly increased the expression of pro-apoptotic proteinsBad, using real-time PCR analysis (mRNA for Bcl-2 family proteins) resulted Bcl-2's expression is negatively regulated.

CONCLUSION

Osteosarcoma (SAOS2) cell lines' proliferation, migration, and ability to proliferate were reduced markedly by rutin fraction and it also causes apoptosis of Osteosarcoma cell lines (SAOS2).

Changes in Cooking Characteristics, Structural Properties and Bioactive Components of Wheat Flour Noodles Partially Substituted with Whole-Grain Hulled Tartary Buckwheat Flour

The whole-grain, hulled Tartary buckwheat flour (HTBF) with outstanding bioactive functions was prepared, and the effects of partial substitution ratios (0, 30%, 51% and 70%) of wheat flour with HTBF on the characteristics of TB noodles (TBNs) were investigated, mainly including the cooking characteristics, sensory analysis, internal structure, bioactive components, and in vitro starch digestibility. With an increasing replacement level of HTBF, the water absorption index of the noodles decreased, whereas the cooking loss increased. A sensory analysis indicated that there were no off-flavors in all TBN samples. The scanning electron microscope images presented that the wheat noodles, 30% TBNs and 70% TBNs had dense and uniform cross sections. Meanwhile, the deepest color, V-type complexes, and lowest crystallinity (13.26%) could be observed in the 70% TBNs. A HTBF substitution increased the rutin content and the total phenolic and flavonoid contents in the TBNs, and higher values were found in the 70% TBNs. Furthermore, the lowest rapidly digestible starch content (16%) and highest resistant starch content (66%) were obtained in the 70% TBNs. Results demonstrated that HTBF could be successfully applied to make TBNs, and a 70% substitution level was suggested. This study provides consumers with a good option in the realm of special noodle-type products.

In Vitro Bioactivities of Commonly Consumed Cereal, Vegetable, and Legume Seeds as Related to Their Bioactive Components: An Untargeted Metabolomics Approach Using UHPLC-QTOF-MS2

We conducted a comprehensive evaluation of the antioxidant, anti-obesity, anti-diabetic, and anti-glycation activities associated with the consumption of broccoli, red cabbage, alfalfa, and buckwheat seeds. Additionally, we explored the relationship between these biological activities and the profiles of amino acids, polyphenols, and organic acids identified in the seeds. Our findings demonstrated that red cabbage, broccoli, and buckwheat extracts exhibited significantly higher antioxidant potential compared to the alfalfa extract. Moreover, buckwheat displayed the most significant capacity for inhibiting alpha-glucosidase. Remarkably, broccoli and red cabbage demonstrated substantial anti-glycation and lipase inhibitory potentials. We identified the presence of amino acids, polyphenols, and organic acids in the extracts through untargeted metabolomics analysis. Correlation analysis revealed that pyroglutamic acid positively correlated with all the investigated functional properties. Most polyphenols made positive contributions to the functional properties, with the exception of ferulic acid, which displayed a negative correlation with all tested biological activities. Furthermore, gluconic acid and arabinonic acid among the organic acids identified displayed a positive correlation with all the functional properties. These results strongly support the anti-diabetic, anti-obesity, and anti-glycation potential of red cabbage, broccoli, and buckwheat seeds.

Stability of Phenols, Antioxidant Capacity and Grain Yield of Six Rice Genotypes

The environment is the main factor affecting variations in phytochemicals and antioxidant activity in rice. The objective of this study was to evaluate the stability of grain yield, phytochemicals and antioxidant capacity of six rice genotypes. Six rice genotypes were evaluated in a randomized complete block design with three replicates at three locations in Trat, Bangkok and Sakon Nakhon provinces in July-October 2019. Data on grain yield, yield components, total phenolic content, ferulic acid and antioxidant capacity were recorded. Grain yield was highest for crops grown in Bangkok, whereas antioxidant activity was highest for crops grown in Bangkok and Sakon Nakhon. Hom Nang Nual 1 and Mali Nil Boran had the highest grain yield. Riceberry had the highest grain yield in Trat; it also had high levels of total phenolic compounds, ferulic acid and antioxidant activity. Mali Nil Boran, Mali Nil Surin and Riceberry had the most stable total phenolic content, ferulic acid and antioxidant activity, respectively. Information on the levels and variability of phytochemicals in rice enables the selection of genotypes with high and stabile phytochemicals for production and rice breeding.

A review: The nutrition components, active substances and flavonoid accumulation of Tartary buckwheat sprouts and innovative physical technology for seeds germinating

Compared with the common grain, Tartary buckwheat enjoys higher nutritional value. Some distinctive nutrition associated with physiological activity of Tartary buckwheat is valuable in medicine. In addition, it's a good feed crop. In the paper, the main components (starch, protein, amino acid, fatty acid and mineral) and polyphenol bioactive components in Tartary buckwheat and its sprouts were reviewed, and the accumulation of flavonoids in sprouts during germination, especially the methods, synthetic pathways and mechanisms of flavonoid accumulation was summarized. The research on bioactive components and health benefits of Tartary buckwheat also were reviewed. Besides, the applications of innovative physical technology including microwave, magnetic, electromagnetic, ultrasonic, and light were also mentioned and highlighted, which could promote the enrichment of some active substances during seeds germination and growth of Tartary buckwheat sprouts. It would give a good support and benefit for the research and processing of Tartary buckwheat and its sprouts in next day.

Development of a Comprehensive Quality Evaluation System for Foxtail Millet from Different Ecological Regions

Foxtail millet (Setaria italica L.) is a critical grain with high nutritional value and the potential for increased production in arid and semiarid regions. The foxtail millet value chain can be upgraded only by ensuring its comprehensive quality. Thus, samples were collected from different production areas in Shanxi province, China, and compared in terms of quality traits. We established a quality evaluation system utilizing multivariate statistical analysis. The results showed that the appearance, nutritional content, and culinary value of foxtail millet produced in different ecological regions varied substantially. Different values of amino acids (DVAACs), alkali digestion values (ADVs), and total flavone content (TFC) had the highest coefficients of variation (CVs) of 50.30%, 39.75%, and 35.39%, respectively. Based on this, a comprehensive quality evaluation system for foxtail millet was established, and the quality of foxtail millet produced in the five production areas was ranked in order from highest to lowest: Dingxiang > Zezhou > Qinxian > Xingxian > Yuci. In conclusion, the ecological conditions of Xinding Basin are favorable for ensuring the comprehensive quality of foxtail millet. .

Specialized Metabolites Accumulation Pattern in Buckwheat Is Strongly Influenced by Accession Choice and Co-Existing Weeds

Screening suitable allelopathic crops and crop genotypes that are competitive with weeds can be a sustainable weed control strategy to reduce the massive use of herbicides. In this study, three accessions of common buckwheat Fagopyrum esculentum Moench. (Gema, Kora, and Eva) and one of Tartary buckwheat Fagopyrum tataricum Gaertn. (PI481671) were screened against the germination and growth of the herbicide-resistant weeds Lolium rigidum Gaud. and Portulaca oleracea L. The chemical profile of the four buckwheat accessions was characterised in their shoots, roots, and root exudates in order to know more about their ability to sustainably manage weeds and the relation of this ability with the polyphenol accumulation and exudation from buckwheat plants. Our results show that different buckwheat genotypes may have different capacities to produce and exude several types of specialized metabolites, which lead to a wide range of allelopathic and defence functions in the agroecosystem to sustainably manage the growing weeds in their vicinity. The ability of the different buckwheat accessions to suppress weeds was accession-dependent without differences between species, as the common (Eva, Gema, and Kora) and Tartary (PI481671) accessions did not show any species-dependent pattern in their ability to control the germination and growth of the target weeds. Finally, Gema appeared to be the most promising accession to be evaluated in organic farming due to its capacity to sustainably control target weeds while stimulating the root growth of buckwheat plants.

Tartary Buckwheat Bran: A Review of Its Chemical Composition, Processing Methods and Food Uses

Tartary buckwheat (Fagopyrum tataricum Gaertn.) containing large amounts of functional compounds with antioxidant activity, such as rutin, has attracted substantial research attention due to its industrial applications. Particularly, the functional compounds in Tartary buckwheat bran, an unexploited byproduct of the buckwheat flour milling process, are more concentrated than those in Tartary buckwheat flour. Thus, Tartary buckwheat bran is deemed to be a potential material for making functional foods. However, a review that comprehensively summarizes the research on Tartary buckwheat bran is lacking. Therefore, we highlighted current studies on the chemical composition of Tartary buckwheat bran. Moreover, the processing method and food uses of Tartary buckwheat bran are also discussed.

Nutritional and bioactive characteristics of buckwheat, and its potential for developing gluten-free products: An updated overview

In the present era, food scientists are concerned about exploiting functional crops with nutraceutical properties. Buckwheat is one of the functional pseudocereals with nutraceutical components used in the treatment of health-related diseases, malnutrition, and celiac diseases. As a preferred diet as a gluten-free product for celiac diseases, buckwheat is a good source of nutrients, bioactive components, phytochemicals, and antioxidants. The general characteristics and better nutritional profile of buckwheat than other cereal family crops were highlighted by previous investigations. In buckwheats, bioactive components like peptides, flavonoids, phenolic acids, d-fagomine, fagopyritols, and fagopyrins are posing significant health benefits. This study highlights the current knowledge about buckwheat and its characteristics, nutritional constituents, bioactive components, and their potential for developing gluten-free products to target celiac people (1.4% of the world population) and other health-related diseases.

Tartary Buckwheat Grain as a Source of Bioactive Compounds in Husked Groats

Tartary buckwheat (Fagopyrum tataricum Gaertn.) originates in mountain regions of Western China, and is cultivated in China, Bhutan, Northern India, Nepal, and Central Europe. The content of flavonoids in Tartary buckwheat grain and groats is much higher than in common buckwheat (Fagopyrum esculentum Moench), and depends on ecological conditions, such as UV-B radiation. Buckwheat intake has preventative effects in chronic diseases, such as cardiovascular diseases, diabetes, and obesity, due to its content of bioactive substances. The main bioactive compounds in Tartary buckwheat groats are flavonoids (rutin and quercetin). There are differences in the bioactivities of buckwheat groats obtained using different husking technologies, based on husking raw or pretreated grain. Husking hydrothermally pretreated grain is among the traditional ways of consuming buckwheat in Europe and some parts of China and Japan. During hydrothermal and other processing of Tartary buckwheat grain, a part of rutin is transformed to quercetin, the degradation product of rutin. By adjusting the humidity of materials and the processing temperature, it is possible to regulate the degree of conversion of rutin to quercetin. Rutin is degraded to quercetin in Tartary buckwheat grain due to the enzyme rutinosidase. The high-temperature treatment of wet Tartary buckwheat grain is able to prevent the transformation of rutin to quercetin.

Polyphenol Profile and In Vitro Antioxidant and Enzyme Inhibitory Activities of Different Solvent Extracts of Highland Barley Bran

Five different solvent extracts of highland barley bran were analyzed and compared for their polyphenol profile, antioxidant activity, and α-glucosidase and α-amylase inhibitory activities. The highland barley bran acetone extract had the highest total phenolic content, total flavonoid content, and antioxidant capacity. It was followed by the methanol and ethanol extracts, while n-butanol and ethyl acetate extracts exhibited lower measured values. Diosmetin, luteolin, protocatechuic acid, vanillic acid, ferulic acid, phlorogucinol, diosmin, isoquercitrin, catechin, and isovitexin were among the most abundant phenolic compounds identified in different solvent extracts, and their concentrations varied according to the solvent used. The highest α-glucosidase and α-amylase inhibitory activity were observed in the ethyl acetate extract of highland barley bran, followed by the acetone and methanol extracts. In contrast, n-butanol and ethanol extracts exhibited lower measured values. The different solvent extracts were effective inhibitors for α-glucosidase and α-amylase with activity reaching to 34.45-94.32% and 22.08-35.92% of that of positive control acarbose, respectively. There were obvious correlations between the phenolic content and composition of different solvent extracts and their in vitro antioxidant activity, α-glucosidase inhibition activity and α-amylase inhibition activity. Black barley bran is an excellent natural raw material for developing polyphenol-rich functional foods and shows good antioxidant and hypoglycemic potential to benefit human health.

Antioxidants of Amaranth, Quinoa and Buckwheat Wholemeals and Heat-Damage Development in Pseudocereal-Enriched Einkorn Water Biscuits

A viable approach to improve the nutritional quality of cereal-based foods is their enrichment with pseudocereals. The aim of this research was to evaluate the antioxidant properties of amaranth, quinoa and buckwheat, and the heat damage of water biscuits (WB) produced from either wholemeal or refined flour of einkorn and enriched with 50% buckwheat, amaranth or quinoa wholemeal. Buckwheat had the highest tocols content (86.2 mg/kg), and einkorn the most carotenoids (5.6 mg/kg). Conjugated phenolics concentration was highest in buckwheat (230.2 mg/kg) and quinoa (218.6 mg/kg), while bound phenolics content was greatest in einkorn (712.5 mg/kg) and bread wheat (675.7 mg/kg). The all-wholemeal WB had greater heat damage than those containing refined flour (furosine: 251.5 vs. 235.8 mg/100 g protein; glucosylisomaltol: 1.0 vs. 0.6 mg/kg DM; hydroxymethylfurfural: 4.3 vs. 2.8 mg/kg DM; furfural: 8.6 vs. 4.8 mg/kg DM). The 100% bread wheat and einkorn wholemeal WB showed greater heat damage than the WB with pseudocereals (furfural, 9.2 vs. 5.1 mg/kg; glucosylisomaltol 1.1 vs. 0.7 mg/kg). Despite a superior lysine loss, the amino-acid profile of the pseudocereals-enriched WB remained more balanced compared to that of the wheats WB.

Evaluation of Nutritional Components, Phenolic Composition, and Antioxidant Capacity of Highland Barley with Different Grain Colors on the Qinghai Tibet Plateau

The nutritional composition, polyphenol and anthocyanin composition, and antioxidant capacity of 52 colored highland barley were evaluated. The results showed that the protein content of highland barley in the black group was the highest, the total starch and fat contents in the blue group were the highest, the amylose content in the purple group was quite high, the fiber content in the yellow group was quite high, and the β-glucan content of the dark highland barley (purple, blue and black) was quite high. The polyphenol content and its antioxidant capacity in the black group were the highest, while the anthocyanin content and its antioxidant capacity in the purple highland barley were the highest. Ten types of monomeric phenolic substances were the main contributors to DPPH, ABTS, and FRAP antioxidant capacity. All varieties could be divided into four categories according to nutrition or function. The grain color could not be used as an absolute index to evaluate the quality of highland barley, and the important influence of variety on the quality of highland barley also needed to be considered. In actual production, suitable raw materials must be selected according to the processing purpose and variety characteristics of highland barley.

CRISPR/Cas9-Mediated Targeted Mutagenesis of FtMYB45 Promotes Flavonoid Biosynthesis in Tartary Buckwheat (Fagopyrum tataricum)

The clustered regularly interspaced short palindromic repeat/CRISPR-associated protein 9 (CRISPR/Cas9) technology is an efficient genome editing tool used in multiple plant species. However, it has not been applied to Tartary buckwheat (Fagopyrum tataricum), which is an important edible and medicinal crop rich in rutin and other flavonoids. FtMYB45 is an R2R3-type MYB transcription factor that negatively regulates flavonoid biosynthesis in Tartary buckwheat. Here, the CRISPR/Cas9 system polycistronic tRNA-sgRNA (PTG)/Cas9 was employed to knock out the FtMYB45 gene in Tartary buckwheat. Two single-guide RNAs (sgRNAs) were designed to target the second exon of the FtMYB45 gene. Twelve transgenic hairy roots were obtained using Agrobacterium rhizogenes-mediated transformation. Sequencing data revealed that six lines containing six types of mutations at the predicted double-stranded break site were generated using sgRNA1. The mutation frequency reached 50%. A liquid chromatography coupled with triple quadrupole mass spectrometry (LC-QqQ-MS) based metabolomic analysis revealed that the content of rutin, catechin, and other flavonoids was increased in hairy root mutants compared with that of lines transformed with the empty vector. Thus, CRISPR/Cas9-mediated targeted mutagenesis of FtMYB45 effectively increased the flavonoids content of Tartary buckwheat. This finding demonstrated that the CRISPR/Cas9 system is an efficient tool for precise genome editing in Tartary buckwheat and lays the foundation for gene function research and quality improvement in Tartary buckwheat.

Tea Infusions as a Source of Phenolic Compounds in the Human Diet

Phenolic compounds are components with proven beneficial effects on the human body, primarily due to their antioxidant activity. In view of the high consumption of tea and the numerous factors that affect the nutritional value of its infusions, the aim of this study was to identify the effects of tea type and duration of leaf extraction with water on the levels of phenolic compounds and other components that determine biological activity (oxalates, Ca, Na, Cu, and Mn). Based on assays, infusions of red tea prepared for 20 min were found to be the best source of phenolics (202.9 mg/100 mL), whereas the lowest level of these compounds was determined in infusions of black tea extracted from leaves for 30 min (46.9 mg/100 mL). The highest degree of increase in polyphenol content (by approx. 50%) was noted in red and green tea infused for between 10 and 20 min, whereas for black tea, polyphenol levels decreased with time. The biological activity of tea infusions appears to be determined to the greatest extent by the interactions between phenolic compounds and oxalates (r = 0.6209), calcium (r = 0.8516), and sodium (0.8045). A daily intake of three to four mugs (1 L) of tea infusions provides the human body the entire amount of phenolics recommended for health reasons (as regards red tea, this is possible at 1/3 of the volume) and covers the daily requirement for manganese, as well as (partially) copper.

Genome-wide identification and expression analysis of the plant-specific PLATZ gene family in Tartary buckwheat (Fagopyrum tataricum)

BACKGROUND

Plant AT-rich sequence and zinc-binding (PLATZ) proteins belong to a novel class of plant-specific zinc-finger-dependent DNA-binding proteins that play essential roles in plant growth and development. Although the PLATZ gene family has been identified in several species, systematic identification and characterization of this gene family has not yet been carried out for Tartary buckwheat, which is an important medicinal and edible crop with high nutritional value. The recent completion of Tartary buckwheat genome sequencing has laid the foundation for this study.

RESULTS

A total of 14 FtPLATZ proteins were identified in Tartary buckwheat and were classified into four phylogenetic groups. The gene structure and motif composition were similar within the same group, and evident distinctions among different groups were detected. Gene duplication, particularly segmental duplication, was the main driving force in the evolution of FtPLATZs. Synteny analysis revealed that Tartary buckwheat shares more orthologous PLATZ genes with dicotyledons, particularly soybean. In addition, the expression of FtPLATZs in different tissues and developmental stages of grains showed evident specificity and preference. FtPLATZ3 may be involved in the regulation of grain size, and FtPLATZ4 and FtPLATZ11 may participate in root development. Abundant and variable hormone-responsive cis-acting elements were distributed in the promoter regions of FtPLATZs, and almost all FtPLATZs were significantly regulated after exogenous hormone treatments, particularly methyl jasmonate treatment. Moreover, FtPLATZ6 was significantly upregulated under all exogenous hormone treatments, which may indicate that this gene plays a critical role in the hormone response of Tartary buckwheat.

CONCLUSIONS

This study lays a foundation for further exploration of the function of FtPLATZ proteins and their roles in the growth and development of Tartary buckwheat and contributes to the genetic improvement of Tartary buckwheat.

Effect of particle size on the release behavior and functional properties of wheat bran phenolic compounds during in vitro gastrointestinal digestion

Wheat bran is a rich source of phenolic compounds, and the health benefits of phenolic compounds depend on its bioaccessibility. The release behavior and functional properties of phenolic compounds in different particle size wheat bran during in vitro digestion were investigated. Coarse wheat bran (CWB, 1110.39 μm) was milled by airflow impact mill to produce medium wheat bran (MWB, 235.68 μm), fine wheat bran (FWB, 83.73 μm) and superfine wheat bran (SWB, 19.16 μm). The reduction in particle size increased the release of phenolic compounds, mainly ferulic acid, after digestion. The free p-coumaric acid content in SWB was nearly five times higher than that in CWB, MWB and FWB due to the complete destruction of aleurone cell walls. Moreover, SWB showed higher bioaccessible phenolic compounds content (65.51%) than CWB. The improved phenolic bioaccessibility increased the antioxidant capacities and carbohydrate-digestive enzymes inhibitory activities of SWB and significantly reduced its starch digestibility.

Morphological, phytochemical and genetic diversity of threatened Polygonatum verticillatum (L.) All. populations of different altitudes and habitat types in Himalayan region

Polygonatum verticillatum (L.) All. is an important medicinal herb that belongs to the family Asparagaceae. The rhizome of the species is used in Chyavanprash preparation and several other ayurvedic formulations. Numerous active constituents like saponins, alkaloids, phytohormones, flavonoids, antioxidants, lysine, serine, aspartic acid, diosgenin, β-sitosterol, etc. have been reported from this species. In this study, morphological, phytochemical, antioxidant and genetic variations of 11 distant populations of P. verticillatum were measured. Considerably (P < 0.05) higher variations were recorded among different populations of P. verticillatum using morphological, phytochemical and genetic diversity parameters. AGFW (above ground fresh weights); flavonols, FRAP (Ferric ion reducing antioxidant power) and NO (Nitric Oxide scavenging activity) were recorded maximum in Kafni population. Similarly, a significantly higher above and below ground dry weight was recorded in Mayawati and Surmoli populations respectively. Maximum phenolic content, tannins, and DPPH (2,2-diphenyl-1-picrylhydrazyl) activity were recorded in Milam population. A total of 165 individuals from 11 populations were assessed for genetic diversity using inter-simple sequence repeats (ISSR) marker. High genetic diversity (He = 0.35) was recorded in Himkhola and Surmoli populations while it was observed minimum (0.28) in the Mayawati population. Altitude showed a significant positive correlation with tannins (r = 0.674; P < 005) and DPPH (r = 0.820; P < 0.01). Phenol content exhibited a considerably positive relationship with He (r = 0.606; P < 0.05) and BGFW (r = 0.620; P < 0.05), flavonol displayed a positive correlation with Pp% (r = 0.606; P < 0.05). The population structure of P. verticillatum, exhibited that the optimal value of the K was 3 for its populations as determined by the ΔK statistic structure. Among populations, the amount of gene flow is higher (Nm = 1.717) among all sites. Hence, it can be concluded that P. verticillatum populations possess considerable variability in the collected populations. Likewise, the populations from Kafni, Satbunga and Himkhola with higher morphological, phytochemicals and genetic variability were prioritized and therefore recommended for cultivation and mass multiplication to meet the industrial demand for target species.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12298-021-01044-9.

Distribution of polyphenolic and sugar compounds in different buckwheat plant parts

The aim of this study was to provide information on the phenolic and sugar profiles of different parts of the buckwheat plant, which can define that buckwheat is a functional food, with a high nutritional value and very useful for human health. Therefore, the extracts of buckwheat leaf, stem, and flower, as well as buckwheat grain were analysed for the content of polyphenol and antioxidant tests. The identification of a notable number of phenolic compounds and quantification of sugars in different parts of buckwheat indicates that buckwheat is a highly valuable plant. A total of 60 phenolic compounds were identified (18 cinnamic acid derivatives, 14 flavonols, 13 flavan-3-ols (including proanthocyanidins), 10 hydroxybenzoic acid derivatives, and 5 flavones) using ultra-high-performance liquid chromatography (UHPLC), coupled with a hybrid mass spectrometer which combines the Linear Trap Quadrupole (LTQ) and OrbiTrap mass analyzer. The highest number of phenolic compounds was found in the analysed buckwheat flower sample, and then in the leaf, followed by the grain and the stem. In addition, the sugar profile of buckwheat leaf, stem, flower and grain, as well as the buckwheat pollen and the nectar was analysed. Hence, 16 sugars and 5 sugar alcohols were detected by the high-performance anion exchange chromatography (HPAEC) with a pulsed amperometric detector (PAD). Sucrose was found in a significant amount with the highest content in buckwheat leaf. Trisaccharides had similar accumulation in the sample extracts, while disaccharides dominated in buckwheat leaf, followed by nectar and pollen. The sugar alcohols showed the highest content in buckwheat grain, where erythritol was predominant. The obtained results show that buckwheat is very rich in phenolic compounds and sugars. In addition to grain, the other parts of the buckwheat plant can be used as a very good source of different classes of phenolic compounds. This study provides useful information on the distribution of phytochemicals in different parts of the buckwheat plant, which contribute to the maintaining of the status of buckwheat as a functional food.

The aim of this study was to provide information on the phenolic and sugar profiles of different parts of the buckwheat plant, which can define that buckwheat is a functional food, with a high nutritional value and very useful for human health.

Bioactive Compounds in Different Buckwheat Species

The accumulation of valuable nutrients in cereal grains depends on a number of factors, including species, cultivars, and environment conditions. The aim of this study was to compare protein, some polyphenols and rutin content, as well as mineral composition in Fagopyrum tataricum and Fagopyrum esculentum genotypes growing in Polish conditions. A field experiment was conducted on pseudopodsolic soil in 2017-2018 at the Experimental Station in Osiny (51°35', 21°55'), following randomized complete block method with three replications. Two cultivars of Fagophyrum esculentum (Kora and Panda), two cultivars of Fagopyrum tataricum (LIT1 and 63181) and two forms of Fagopyrum esculentum (Red Corolla and Green Corolla) were used in this experiment. We found differences in the tested compounds (protein, phenolic acids, rutin, and mineral composition) between cultivars and genotypes. Total phenolic acid and rutin contents were higher in the Fagopyrum tataricum compared to Fagopyrum esculentum. Ferulic and coumaric acids were prominent in the Kora and Panda cultivars, however vanillic and syringic acids accumulated more in Green Corolla and Red Corolla. The common buckwheat seeds contained more Cu, Mn, and Mg and less Ca than tartary buckwheat. Moreover Fagopytum esculentum genotype contains more protein compared to Fagopyrum tataricum.

Comparison of the Chemical and Technological Characteristics of Wholemeal Flours Obtained from Amaranth (Amaranthus sp.), Quinoa (Chenopodium quinoa) and Buckwheat (Fagopyrum sp.) Seeds

A sound fundamental knowledge of the seed and flour characteristics of pseudocereals is crucial to be able to promote their industrial use. As a first step towards a more efficient and successful application, this study focuses on the seed characteristics, chemical composition and technological properties of commercially available pseudocereals (amaranth, quinoa, buckwheat). The levels of starch, fat, dietary fiber and minerals were comparable for amaranth and quinoa seeds but the protein content is higher in amaranth. Due to the high amount of starch, buckwheat seeds are characterised by the lowest amounts of fat, dietary fibre and minerals. Its protein content ranged between that of amaranth and quinoa. Buckwheat seeds were larger but easily reduced in size. The lipid fraction of the pseudocereals mostly contained unsaturated fatty acids, with the highest prevalence of linoleic and oleic acid. Palmitic acid is the most abundant unsaturated fatty acid. Moreover, high levels of P, K and Mg were found in these pseudocereals. The highest phenolic content was found in buckwheat. Amaranth WMF (wholemeal flour) had a high swelling power but low shear stability. The pasting profile strongly varied among the different quinoa WMFs. Buckwheat WMFs showed high shear stability and rate of retrogradation.

Tea as a Source of Biologically Active Compounds in the Human Diet

Due to the different levels of bioactive compounds in tea reported in the literature, the aim of this study was to determine whether commercially available leaf teas could be an important source of phenolics and selected minerals (copper, manganese, iron, zinc, magnesium, calcium, sodium, potassium) and if the differences in the content of these components between various types of tea are significant. It was found that both the amount of these compounds in tea and the antioxidant activity of tea infusions were largely determined by the origin of tea leaves as well as the processing method, which can modify the content of the studied components up to several hundred-fold. The group of green teas was the best source of phenolic compounds (110.73 mg/100 mL) and magnesium (1885 µg/100 mL) and was also characterised by the highest antioxidant activity (59.02%). This type of tea is a great contributor to the daily intake of the studied components. The average consumption of green tea infusions, assumed to be 3–4 cups (1 L) a day, provides the body with health-promoting polyphenol levels significantly exceeding the recommended daily dose. Moreover, drinking one litre of an unfermented tea infusion provides more than three times the recommended daily intake of manganese. Tea infusions can be a fairly adequate, but only a supplementary, source of potassium, zinc, magnesium, and copper in the diet. Moreover, it could be concluded that the antioxidant activity of all the analysed types of tea infusions results not only from the high content of phenolic compounds and manganese but is also related to the presence of magnesium and potassium.

Coarse Cereals and Legume Grains Exert Beneficial Effects through Their Interaction with Gut Microbiota: A Review

Coarse cereals and legume grains (CCLGs) are rich in specific macro- and functional elements that are considered important dietary components for maintaining human health. Therefore, determining the precise nutritional mechanism involved in exerting the health benefits of CCLGs can help understand dietary nutrition in a better manner. Evidence suggests that gut microbiota play a crucial role in the function of CCLGs via their complicated interplay with CCLGs. First, CCLGs modulate gut microbiota and function. Second, gut microbiota convert CCLGs into compounds that perform different functions. Third, gut microbiota mediate interactions among different CCLG components. Therefore, using gut microbiota to expound the nutritional mechanism of CCLGs is important for future studies. A precise and rapid gut microbiota research model is required to screen and evaluate the quality of CCLGs. The outcomes of such research may promote the rapid discovery, classification, and evaluation of CCLG resources, thereby opening a new opportunity to guide nutrition-based development of CCLG products.

Probiotic-fermented black tartary buckwheat alleviates hyperlipidemia and gut microbiota dysbiosis in rats fed with a high-fat diet

Natural plants fermented with probiotics exert beneficial effects on hyperlipidemia and gut microbiota disorders. This study aimed to investigate the hypolipidemic activity of fermented black tartary buckwheat (FBTB) in rats with hyperlipidemia induced by a high-fat diet (HFD) in association with the regulation of gut microbiota. Probiotic fermentation by Bacillus sp. DU-106 obviously increased the contents of tyrosine, lysine, total flavonoids, total polyphenols, quercetin, and kaempferol in black tartary buckwheat (BTB) and significantly decreased the rutin content. FBTB treatment for 8 weeks significantly decreased the levels of serum total cholesterol, triglycerides, and low-density lipoprotein cholesterol in HFD-induced hyperlipidemic rats. Western blot analysis further confirmed that the protein expression levels of FXR, SREBP1, and PPARα were altered after FBTB treatment. Moreover, FBTB intervention altered the gut microbiota of HFD-fed rats by increasing the relative abundances of Lactobacillus, Faecalibaculum, and Allobaculum and decreasing the relative abundance of Romboutsia. The relative abundance of Allobaculum was positively correlated with the levels of tyrosine, total flavonoids, total polyphenols, quercetin and kaempferol and negatively correlated with that of rutin. These results suggested that FBTB could alleviate hyperlipidemia and gut microbiota dysbiosis in HFD-fed rats.

Cereal grain-based functional beverages: from cereal grain bioactive phytochemicals to beverage processing technologies, health benefits and product features

Increased consumer awareness of health and wellness has promoted a high demand for foods and beverages with functional and therapeutic properties. Cereals, apart from being important staple crops and primary sources of energy and nutrition, are replete with bioactive phytochemicals with health properties. Cereal grains contain a diverse range of bioactive phytochemicals including phenolic compounds, dietary fibers, carotenoids, tocols, phytosterols, γ-oryzanol, and phytic acid and therefore have great potential for processing into functional beverages. Although there are a variety of cereal grain-based beverages produced world-wide, very little scientific and technological attention has been paid to them. In this review, we have discussed cereal grain-based functional beverages based on 3 main categories: cereal grain-based milk alternatives, roasted cereal grain teas, fermented nonalcoholic cereal grain beverages. The processing techniques, health properties and product features of these beverages are elaborated, and the challenges and future perspectives are proposed. As the food market becomes increasingly diverse, cereal grain-based beverages could be a promising new category of health functional beverages in our daily life.

Buckwheat Secondary Metabolites: Potential Antifungal Agents

Research groups have put significant emphasis on the evaluation of nutritional, health-promoting, and other biological activities of secondary metabolites from buckwheat. Among these phytochemicals, phenolic and lipophilic antioxidants, particularly, phenolic acids, flavonoids, and tocopherols, have been the focus of the latest studies since antioxidant activity has recently been associated with the possibility of inhibiting fungal growth and mycotoxin biosynthesis. The mycotoxin contamination of cereal and pseudocereal grains caused primarily by Fusarium, Penicillium, and Aspergillus species poses a significant hazard to human health. Therefore, efforts to examine the involvement of plant antioxidants in the biosynthesis of mycotoxins at the transcriptional level have emerged. In addition, hydrophobic interactions of buckwheat phenolics with cell membranes could also explain their capacity to reduce fungal development. Eventually, possibilities of enhancing the biological activity of cereal and pseudocereal phytochemicals have been studied, and sourdough fermentation has been proposed as an efficient method to increase antioxidant activities. This effect could result in an increased antifungal effects of sourdough and bakery products. This review reports the main advances in research on buckwheat phenolics and other antioxidant phytochemicals, highlighting possible mechanisms of action and processes that could improve their biological activities.

Effect of Roasting and Brewing on the Antioxidant and Antiproliferative Activities of Tartary Buckwheat

We evaluated the effect of the roasting and brewing conditions of Tartary buckwheat (TB), which is widely used in infusion teas, on its antioxidant and antiproliferative activities in vitro. TB was roasted at 210 °C for 10 min and brewed at a high temperature for a short time (HTST; 85–90 °C, 3 min) or at room temperature for a long time (RTLT; 25–30 °C, 24 h). Roasted TB (RTB) tea brewed at RTLT had the highest total polyphenol content (TPC) and total flavonoid content (TFC) among the four TB teas for different roasting and brewing conditions. Moreover, RTB brewed at RTLT showed the greatest 2,2-diphenyl-1-picrylhydrazyl-, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)-, and alkyl-scavenging activities. The TB tea brewed at RTLT had higher Fe²⁺-chelating activity than that brewed at HTST, irrespective of roasting. Moreover, RTB tea brewed at RTLT inhibited the proliferation of human pancreatic and breast cancer cells. Overall, RTB-RTLT displayed the largest effect on antioxidant and antiproliferative effects. Finally, rutin was found to possess the most pronounced effect on the antioxidant and antiproliferative activities of the TB teas. These results indicate that the antioxidant and antiproliferative activities of RTB are enhanced by RTLT brewing.

A systematic review of phytochemicals in oat and buckwheat

Consumption of oat and buckwheat have been associated with various health benefits that may be attributed to their nutritional composition. We performed a systematic review to evaluate the profile and quantity of bioactive compounds present in oat and buckwheat. Among 154 studies included in final analysis, 113 and 178 bioactive compounds were reported in oat and buckwheat, respectively. Total phytosterols, tocols, flavonoids and rutin content were generally higher in buckwheat, β-glucans were significantly higher in oat, while avenanthramides and saponins were characteristically present in oat. The majority of studies included in current review were published before 2010s. The heterogeneous methodological procedures used across the studies precluded our possibility to meta-analyse the evidence and raises the need for harmonization of separation and extraction methods in future studies. Our findings should further stimulate the exploration of metabolites related to identified phytochemicals and their roles in human health.

The effect of antifungal extracts on the contamination of grain with microfungi

The study aimed to analyze the effects of extracts made from buckwheat grain, hulls, and bee products (propolis, bread, and pollen) and extraction solvents on the growth of microfungi on a medium and on buckwheat, wheat, oat, and maize grain. Research findings suggest that bioactive compounds contained in buckwheat grain reduced the amount of Fusarium spp. in the grain kept in the antifungal extract for 90 min at 25°C temperature. Buckwheat hull extract was more effective in inhibiting mycelial growth of mycotoxin‐producing Fusarium culmorum and Fusarium graminearum compared with buckwheat grain extract (13%–50% and 14%–36%, respectively). The antifungal activity of extracts of bee products did not depend on the content of phenolic compounds in them; however, it depended on the grain species treated. After treatment of oat, wheat, and maize grain with bee product extracts, the lowest concentration of microfungi was identified on oat grain. More significant analysis results were obtained for the samples where ethanol solvent had been used for the preparation of extracts.

Variability in morphology, phytochemicals, and antioxidants in Polygonatum verticillatum (L.) All. populations under different altitudes and habitat conditions in Western Himalaya, India

Polygonatum verticillatum (L.) All. is one among eight species of Astavarga group of plants known for its vitality strengthening properties and used in different herbal formulations. However, systematic investigation on morphology and antioxidant phytochemicals in relation to different environmental variables like altitude and habitat conditions is poorly available. The present study reveals significant (p < 0.05) differences in structural and functional attributes among sixteen different populations of P. verticillatum in West Himalaya. Among the different populations, plants growing in moist habitat and oak forest exhibited maximum plant height, leaf number, biomass and phytochemical content (total phenolics, tannin, and flavonol). Antioxidant activity using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) positively (p < 0.05) correlated with altitude. Presence of strong antioxidant and DNA damage prevention activity of the species validate its use as vitality strengthening and anti-aging properties. Identified suitable altitude, habitat conditions, and forest types can be utilized for reintroduction of species in to suitable agro-climatic condition. This will also help in obtaining higher quality produce and management practices for conservation of this species.

Buckwheat: A Useful Food and Its Effects on Human Health

:

Buckwheat is a plant used for many purposes, such as consumed as a food and used in the treatment of diseases. It is a good source of many vitamins and minerals and has balanced nutritional value. Because of its nutrient content and many positive effects on human health, buckwheat has become a functional food, recently. Main effects of buckwheat on human health are its hypotensive, hypoglycemic, hypocholesterolemic, neuroprotective and antioxidant effects. Thus, it is considered an alternative food component in dietary treatment for chronic and metabolic diseases, such as diabetes, hypertension and celiac disease. Also, its rich nutrient content supports daily diet and provides a better eating profile. As a result, buckwheat is accepted as a functional food, suggested to improve human health and is used in the treatment of diseases. The aim of this review is to explain some positive effects of buckwheat on human health.

Dynamic changes in polyphenol compounds, antioxidant activity, and PAL gene expression in different tissues of buckwheat during germination

BACKGROUND

There is a growing interest in buckwheat germination regarding the improvement of its health benefits. The aims of this study were to evaluate the effects of germination on polyphenol compounds, antioxidant activity, and phenylalanine ammonia-lyase (PAL) gene expression in different tissues (cotyledon, hypocotyl, and radicle) of buckwheat sprouts during germination for 12 days, as well as to investigate their interactions.

RESULTS

Total polyphenol and total flavonoid contents, antioxidant activity, main polyphenol components, and PAL gene expression significantly increased during germination. On day 12, the rutin content in cotyledons was elevated to 88.6 g kg^-1 , which was 7.7-times and 39.4-times compared to those in buckwheat seeds and radicles, respectively. Meanwhile, chlorogenic acid in hypocotyls reached 7.84 g kg^-1 , which was 36.3-fold higher than those in radicles. However, the PAL gene showed the highest expression in radicles.

CONCLUSION

Present results showed that polyphenol compounds mainly accumulated in cotyledons and hypocotyls. There was a negative correlation between polyphenol compounds and PAL gene expression. The discrepancy suggested that polyphenol compounds might experience transportation within buckwheat sprouts. The study could provide useful information for further application of buckwheat in functional foods, and revelation of the correlation between bioactive components and related gene expressions. © 2018 Society of Chemical Industry.

Digestible indispensable amino acid scores of nine cooked cereal grains

True ileal digestibility (TID) values of amino acid (AA) obtained using growing rats are often used for the characterisation of protein quality in different foods and acquisition of digestible indispensable amino acid scores (DIAAS) in adult humans. Here, we conducted an experiment to determine the TID values of AA obtained from nine cooked cereal grains (brown rice, polished rice, buckwheat, oats, proso millet, foxtail millet, tartary buckwheat, adlay and whole wheat) fed to growing Sprague–Dawley male rats. All rats were fed a standard basal diet for 7 d and then received each diet for 7 d. Ileal contents were collected from the terminal 20 cm of ileum. Among the TID values obtained, whole wheat had the highest values (P<0·05), and polished rice, proso millet and tartary buckwheat had relatively low values. The TID indispensable AA concentrations in whole wheat were greater than those of brown rice or polished rice (P<0·05), and polished rice was the lowest total TID concentrations among the other cereal grains. The DIAAS was 68 for buckwheat, 47 for tartary buckwheat, 43 for oats, 42 for brown rice, 37 for polished rice, 20 for whole wheat, 13 for adlay, 10 for foxtail millet and 7 for proso millet. In this study, the TID values of the nine cooked cereal grains commonly consumed in China were used for the creation of a DIAAS database and thus gained public health outcomes.

Geographic Variation in the Chemical Composition and Antioxidant Properties of Phenolic Compounds from Cyclocarya paliurus (Batal) Iljinskaja Leaves

Cyclocarya paliurus has been widely used as an ingredient in functional foods in China. However, the antioxidant properties of phenolic compounds and the effect of the plant origin remain unclear. The present study evaluated the geographical variation of this plant in term of its phenolic composition and antioxidant activities based on leaf materials collected from five regions. high-performance liquid chromatography (HPLC) analysis showed that there are three major components, quercetin-3-O-glucuronide, kaempferol-3-O-glucuronide, and kaempferol-3-O-rhamnoside, and their contents varied significantly among sampling locations. The investigated phenolic compounds showed substantial antioxidant activities, both in vitro and in vivo, with the highest capacity observed from Wufeng and Jinzhongshan. Correlation analysis revealed that quercetin and kaempferol glycosides might be responsible for the antioxidant activities. Our results indicate the importance of geographic origin, with sunny hours and temperature as the main drivers affecting the accumulation of C. paliurus phenolics and their antioxidant properties.

Phenolics extracted from tartary (Fagopyrum tartaricum L. Gaerth) buckwheat bran exhibit antioxidant activity, and an antiproliferative effect on human breast cancer MDA-MB-231 cells through the p38/MAP kinase pathway

Phenolics extracted from tartary buckwheat (Fagopyrum tartaricum L. Gaerth) bran were analyzed quantitatively and qualitatively. The bioactivity of the phenolic extracts was evaluated, such as the antioxidant activity, and the inhibition capacity on the growth of cancer cells. The molecular mechanism for the inhibitive effect on cancer cells was explored. Results indicated that tartary buckwheat bran phenolics mainly exist in a free form, and free phenolics were twice as abundant as bound phenolics. Free caffeic acid (119.75 μg per 100 mg DW) and bound rutin (51.66 μg per 100 mg DW) represented the main free and bound phenolic compounds, respectively. The free phenolic extract contributed to the major (>90%) antioxidant activities including the oxygen radical antioxidant capacity (ORAC) and cellular antioxidant activity (CAA). The free phenolic extract exhibited anticancer activity for human breast cancer MDA-MB-231 cells in a dose-dependent manner. This significant inhibition effect was achieved through the p38/MAP kinase pathway by inducing cell apoptosis (up-regulating p-p38 and p-ASK1 expressions and down-regulating TRAF2 and p-p53 expressions), and negatively regulating the progression of the cell cycle from the G1 to S phase (increased expression of p21 and suppressed expressions of PCNA, cyclin D1 and CDK4). All these results indicated that tartary buckwheat bran could be a rich resource of natural antioxidants and inhibitors for the growth of MDA-MB-231 cells.