Evaluation of flavonoid contents and antioxidant capacity of the aerial parts of common and tartary buckwheat plants

Rutin distribution in Tartary buckwheat: Identifying prime dietary sources through comparative analysis of post-processing treatments

Rutin is a crucial bioactive compound that determines the nutritional value of Tartary buckwheat (TB). However, the potential of utilizing TB as a dietary source of rutin for human consumption remains largely unexplored. This study aims to address these knowledge gaps by conducting a detailed analysis of rutin content distribution in TB tissues. Our findings revealed a significant variation in rutin content across different plant tissues. Notably, higher levels of rutin were found in embryos and cotyledons compared to other tissues, highlighting them as the primary sites of rutin accumulation in TB seeds and sprouts. Additional research on the processing of TB showed that sprouts and seeds retain high rutin levels even after boiling, steaming, deep-frying, stir-frying, and popping. Comparative analysis of different TB-derived products confirmed that cooked seeds and sprouts can serve as significant dietary sources of rutin. This study offers a foundational framework for the development of future dietary recommendations and applications of TB.

Quantitative predictions of protein and total flavonoids content in Tartary and common buckwheat using near-infrared spectroscopy and chemometrics

A rapid method was developed for determining the total flavonoid and protein content in Tartary buckwheat by employing near-infrared spectroscopy (NIRS) and various machine learning algorithms, including partial least squares regression (PLSR), support vector regression (SVR), and backpropagation neural network (BPNN). The RAW-SPA-CV-SVR model exhibited superior predictive accuracy for both Tartary and common buckwheat, with a high coefficient of determination (R2p = 0.9811) and a root mean squared error of prediction (RMSEP = 0.1071) for flavonoids, outperforming both PLSR and BPNN models. Additionally, the MMN-SPA-PSO-SVR model demonstrated exceptional performance in predicting protein content (R2p = 0.9247, RMSEP = 0.3906), enhancing the effectiveness of the MMN preprocessing technique for preserving the original data distribution. These findings indicate that the proposed methodology could efficiently assess buckwheat adulteration analysis. It can also provide new insights for the development of a promising method for quantifying food adulteration and controlling food quality.

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.

Genome-wide investigation of UDP-Glycosyltransferase family in Tartary buckwheat (Fagopyrum tataricum)

BACKGROUND

Tartary buckwheat (Fagopyrum tataricum) belongs to Polygonaceae family and has attracted increasing attention owing to its high nutritional value. UDP-glycosyltransferases (UGTs) glycosylate a variety of plant secondary metabolites to control many metabolic processes during plant growth and development. However, there have been no systematic reports of UGT superfamily in F. tataricum.

RESULTS

We identified 173 FtUGTs in F. tataricum based on their conserved UDPGT domain. Phylogenetic analysis of FtUGTs with 73 Arabidopsis UGTs clustered them into 21 families. FtUGTs from the same family usually had similar gene structure and motif compositions. Most of FtUGTs did not contain introns or had only one intron. Tandem repeats contributed more to FtUGTs amplification than segmental duplications. Expression analysis indicates that FtUGTs are widely expressed in various tissues and likely play important roles in plant growth and development. The gene expression analysis response to different abiotic stresses showed that some FtUGTs were involved in response to drought and cadmium stress. Our study provides useful information on the UGTs in F. tataricum, and will facilitate their further study to better understand their function.

CONCLUSIONS

Our results provide a theoretical basis for further exploration of the functional characteristics of FtUGTs and for understanding the growth, development, and metabolic model in F. tataricum.

Nutritional Traits, Pasting Properties and Antioxidant Profile of Selected Genotypes of Sorghum, Oat and Maize Eligible for Gluten-Free Products

The technological and nutritional traits of food-grade sorghum hybrids, hulled/naked oat varieties and maize genotypes of different colors were studied for novel and healthier gluten-free foods. Oat genotypes showed the highest protein content, followed by maize and sorghum. The total starch and the total dietary fiber content were quite similar among the three species. Great variation was found in the amylose content, and the highest was in sorghum (27.12%), followed by oat 16.71% and maize 10.59%. Regarding the pasting profile, the rank of Peak Viscosity was sorghum (742.8 Brabender Unit, BU), followed by maize (729.3 BU) and oat (685.9 BU). Oat and sorghum genotypes had similar average breakdown (407.7 and 419.9 BU, respectively) and setback (690.7 and 682.1 BU, respectively), whereas maize showed lower values for both parameters (384.1 BU and 616.2 BU, respectively). The total antioxidant capacity, only in maize, significantly correlated with total flavonoid, phenolic and proanthocyanidin contents, indicating that all the measured compounds contributed to antioxidant capacity. The study indicated the importance of sounding out the nutritional and technological characteristics of gluten-free cereals in order to select suitable cultivars to be processed in different gluten-free foods with better and healthier quality.

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.

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.

Buckwheat: an underutilized crop with attractive sensory qualities and health benefits

The pseudocereal buckwheat is one of the ancient domesticated crops. The aim of the present review was to outline the potential of buckwheat as an agricultural crop and brings studies on buckwheat into a new larger perspective combining current knowledge in agricultural history and practice, nutritional and sensory properties, as well as possible benefits to human health. Historically, buckwheat was an appreciated crop because of its short growth period, moderate requirements for growth conditions, and high adaptability to adverse environments. Nowadays, interest in buckwheat-based food has increased because of its nutritional composition and many beneficial properties for human health. Buckwheat is a rich course of proteins, dietary fibers, vitamins, minerals, and bioactive compounds, including flavonoids. Moreover, it contains no gluten and can be used in the production of gluten-free foods for individuals diagnosed with celiac disease, non-celiac gluten sensitivity, or wheat protein allergies. Buckwheat is traditionally used in the production of various foods and can be successfully incorporated into various new food formulations with positive effects on their nutritional value and attractive sensory properties. Further research is needed to optimize buckwheat-based food development and understand the mechanism of the health effects of buckwheat consumption on human well-being.

Natural Extracts Mitigate the Deleterious Effects of Prolonged Intense Physical Exercise on the Cardiovascular and Muscular Systems

Muscle fatigue is a common symptom induced by exercise. A reversible loss of muscle force is observed with variable rates of recovery depending on the causes or underlying mechanisms. It can not only affect locomotion muscles, but can also affect the heart, in particular after intense prolonged exercise such as marathons and ultra-triathlons. The goal of our study was to explore the effect of four different natural extracts with recognized antioxidant properties on the contractile function of skeletal (locomotion) and cardiac muscles after a prolonged exhausting exercise. Male Wistar rats performed a bout of exhausting exercise on a treadmill for about 2.5 h and were compared to sedentary animals. Some rats received oral treatment of a natural extract (rosemary, buckwheat, Powergrape^®, or rapeseed) or the placebo 24 h and 1 h before exercise. Experiments were performed 30 min after the race and after 7 days of recovery. All natural extracts had protective effects both in cardiac and skeletal muscles. The extent of protection was different depending on muscle type and the duration post-exercise (just after and after one-week recovery), including antiarrhythmic effect and anti-diastolic dysfunction for the heart, and faster recovery of contractility for the skeletal muscles. Moreover, the muscular protective effect varied between natural extracts. Our study shows that an acute antioxidant supplementation can protect against acute abnormal endogenous ROS toxicity, induced here by prolonged exhausting exercise.

Phytochemistry, Bioactivities of Metabolites, and Traditional Uses of Fagopyrum tataricum

In Tartary buckwheat (Fagopyrum tataricum), the edible parts are mainly grain and sprouts. Tartary buckwheat contains protecting substances, which make it possible for plants to survive on high altitudes and under strong natural ultraviolet radiation. The diversity and high content of phenolic substances are important for Tartary buckwheat to grow and reproduce under unfriendly environmental effects, diseases, and grazing. These substances are mainly flavonoids (rutin, quercetin, quercitrin, vitexin, catechin, epicatechin and epicatechin gallate), phenolic acids, fagopyrins, and emodin. Synthesis of protecting substances depends on genetic layout and on the environmental conditions, mainly UV radiation and temperature. Flavonoids and their glycosides are among Tartary buckwheat plants bioactive metabolites. Flavonoids are compounds of special interest due to their antioxidant properties and potential in preventing tiredness, diabetes mellitus, oxidative stress, and neurodegenerative disorders such as Parkinson's disease. During the processing and production of food items, Tartary buckwheat metabolites are subjected to molecular transformations. The main Tartary buckwheat traditional food products are bread, groats, and sprouts.

Molecular Shield for Protection of Buckwheat Plants from UV-B Radiation

Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) and common buckwheat (Fagopyrum esculentum Moench) are adapted to growing in harsh conditions of high altitudes. Ultraviolet radiation at high altitudes strongly impacts plant growth and development. Under the influence of ultraviolet radiation, protecting substances are synthesized in plants. The synthesis of UV-B defense metabolites is genetically conditioned, and their quantity depends on the intensity of the ultraviolet radiation to which the plants and plant parts are exposed. These substances include flavonoids, and especially rutin. Other substances with aromatic rings of six carbon atoms have a similar function, including fagopyrin, the metabolite specific for buckwheat. Defensive substances are formed in the leaves and flowers of common and Tartary buckwheat, up to about the same concentration in both species. In comparison, the concentration of rutin in the grain of Tartary buckwheat is much higher than in common buckwheat. Flavonoids also have other functions in plants so that they can protect them from pests and diseases. After crushing the grains, rutin is exposed to contact with the molecules of rutin-degrading enzymes. In an environment with the necessary humidity, rutin is turned into bitter quercetin under the action of rutin-degrading enzymes. This bitterness has a deterrent effect against pests. Moreover, flavonoids have important functions in human nutrition to prevent several chronic diseases, including obesity, cardiovascular diseases, gallstone formation, and hypertension.

Light Intensity-A Key Factor Affecting Flavonoid Content and Expression of Key Enzyme Genes of Flavonoid Synthesis in Tartary Buckwheat

Tartary buckwheat, a polygonaceae family plant, is rich in abundant flavonoids, high-quality protein, and well-balanced essential amino acids. This study aimed to investigate the effects of climatic variables on the quality of Tartary buckwheat. In this study, six distinct types of Tartary buckwheat collected from the Sichuan Basin, Western Sichuan Plateau, and Yunnan-Guizhou Plateau in southwest China were chosen to investigate the impact of climatic conditions from the grain-filling stage to the harvest stage on the concentration of flavonoids and expression of key enzyme genes involved the synthesis of flavonoids. Meteorological data of three producing areas were collected from the China Meteorological Network, mainly including maximum temperature (Tmax), minimum temperature (Tmin), diurnal temperature difference (Tdif), and light intensity. Then, the contents of rutin, kaempferol-3-O-rutin glycoside, quercetin, and kaempferol in 30 batches of Tartary buckwheat from 6 varieties including Chuanqiao No. 1, Chuanqiao No. 2, Xiqiao No. 1, Xiqiao No. 2, Miqiao No. 1 and Di ku were determined by ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Furthermore, the expression levels of phenylalanine ammonia lyase (PAL), 4-coumaric acid coenzyme A ligase (4CL), and anthocyanin synthase (ANS) in six kinds of Tartary buckwheat were detected by real-time polymerase chain reaction (PCR). The seed photos were processed by ImageJ processing software. The partial least squares method was used to analyze the correlation. As a result, light intensity can promote the accumulation of flavonoids and the expression of key enzyme genes. Miqiao No. 1, which grows in Liangshan Prefecture, Sichuan Province, has the highest light intensity and is the dominant variety with flavonoid content. More importantly, the expression levels of PAL and 4CL in the secondary metabolic pathway of flavonoids were positively correlated with the content of Tartary buckwheat flavonoids. Interestingly, the expression level of ANS was negatively correlated with the content of PAL, 4CL, and flavonoids. In addition, ANS is a key gene affecting the seed coat color of Tartary buckwheat. The higher the expression of ANS, the darker the seed coat color. These findings provide a theoretical basis and reference for the breeding of fine buckwheat varieties.

Antioxidant and anti-obesity effects of in vitro digesta of germinated buckwheat

Buckwheat germinated on days of 3, 5, and 7 was digested in vitro, and the antioxidant and anti-obesity effects of the digesta were evaluated. In vitro digesta of 5 days germinated buckwheat (GBD5) showed significantly higher antioxidant activity in DPPH, ABTS, total phenolic content, total flavonoid content, and ferric reducing antioxidant power by 5.3, 1.3, 2.0, 3.2, and 2.8-fold, respectively than in vitro digesta of non-germinated buckwheat. GBD5 exerted inhibitory effect on total lipid accumulation in 3T3-L1 adipocyte in a dose-dependent manner, with over 25% reduction at 400 µg/mL. Additionally, GBD5 significantly downregulated genes related to adipocyte differentiation and fat accumulation. GBD5 possessed different metabolite profiles compared to others such as higher content of γ-aminobutyric acid and succinic acid. Therefore, GBD5 has potent antioxidant effects and suppresses fat accumulation-related genes and proteins expression, which could act as a new functional substance.

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.

Elucidation of the Regulatory Network of Flavonoid Biosynthesis by Profiling the Metabolome and Transcriptome in Tartary Buckwheat

The characteristics of flavonoid metabolism in different Tartary buckwheat (TB) tissues and the related gene regulation network are still unclear at present. One hundred forty-seven flavonoids were identified from six TB tissues using the ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. The roadmap of the rutin synthesis pathway was revealed. Through transcriptomic analysis it was revealed that the differentially expressed genes (DEGs) are mainly enriched in the "Phenylpropanoid biosynthesis" pathway. Fifty-two DEGs involved in the "flavonol synthesis" pathway were identified. The weighted gene correlation network analysis revealed four co-expression network modules correlated with six flavonol metabolites. Eventually, 74 genes revealed from MEblue and MElightsteelblue modules were potentially related to flavonol synthesis. Of them, 7 MYB transcript factors had been verified to regulate flavonoid synthesis. Furthermore, overexpressed FtMYB31 enhanced the rutin content in vivo. The present findings provide a dynamic flavonoid metabolism profile and co-expression network related to rutin synthesis and are thus valuable in understanding the molecular mechanisms of rutin synthesis in TB.

Concentrations of Phenolic Acids Are Differently Genetically Determined in Leaves, Flowers, and Grain of Common Buckwheat (Fagopyrum esculentum Moench)

Common buckwheat (Fagopyrum esculentum Moench) is a valuable source of proteins, B vitamins, manganese, tryptophan, phytochemicals with an antioxidant effect, and the natural flavonoid rutin. Due to its composition, buckwheat supports the human immune system, regulates blood cholesterol, and is suitable for patients with diabetes or celiac disease. The study aimed to compare the allocation of selected phenolic acids (neochlorogenic acid, chlorogenic acid, trans-caffeic acid, trans-p-coumaric acid, trans-sinapic acid, trans-ferulic acid) and flavonoids (rutin, vitexin, quercetin, kaempferol) in the leaves, flowers, and grain of buckwheat cultivars of different origin. The content of individual phenolics was determined by the HPLC-DAD method. The results confirmed the determining role of cultivar on the relative content of chlorogenic acid, trans-caffeic acid, trans-sinapic acid, vitexin, and kaempferol in buckwheat plants. A significantly negative correlation among concentrations of phenolic acids in different common buckwheat plant parts shows that there are different mechanisms of genetic influences on the concentration of phenolic substances in common buckwheat flowers, leaves, and grain. These differences should be taken into account when breeding buckwheat for a high concentration of selected phenolic substances.

Mapping QTLs for 1000-grain weight and genes controlling hull type using SNP marker in Tartary buckwheat (Fagopyrum tataricum)

BACKGROUND

Tartary buckwheat (Fagopyrum tataricum), an important pseudocereal crop, has high economic value due to its nutritional and medicinal properties. However, dehulling of Tartary buckwheat is difficult owing to its thick and tough hull, which has greatly limited the development of the Tartary buckwheat processing industry. The construction of high-resolution genetic maps serves as a basis for identifying quantitative trait loci (QTLs) and qualitative trait genes for agronomic traits. In this study, a recombinant inbred lines (XJ-RILs) population derived from a cross between the easily dehulled Rice-Tartary type and Tartary buckwheat type was genotyped using restriction site-associated DNA (RAD) sequencing to construct a high-density SNP genetic map. Furthermore, QTLs for 1000-grain weight (TGW) and genes controlling hull type were mapped in multiple environments.

RESULTS

In total, 4151 bin markers comprising 122,185 SNPs were used to construct the genetic linkage map. The map consisted of 8 linkage groups and covered 1444.15 cM, with an average distance of 0.35 cM between adjacent bin markers. Nine QTLs for TGW were detected and distributed on four loci on chromosome 1 and 4. A major locus detected in all three trials was mapped in 38.2-39.8 cM region on chromosome 1, with an LOD score of 18.1-37.0, and explained for 23.6-47.5% of the phenotypic variation. The genes controlling hull type were mapped to chromosome 1 between marker Block330 and Block331, which was closely followed by the major locus for TGW. The expression levels of the seven candidate genes controlling hull type present in the region between Block330 and Block336 was low during grain development, and no significant difference was observed between the parental lines. Six non-synonymous coding SNPs were found between the two parents in the region.

CONCLUSIONS

We constructed a high-density SNP genetic map for the first time in Tartary buckwheat. The mapped major loci controlling TGW and hull type will be valuable for gene cloning and revealing the mechanism underlying grain development and easy dehulling, and marker-assisted selection in Tartary buckwheat.

Assessment of a new artificial buckwheat species Fagopyrum hybridum as a source of plant raw materials compared to F. Tataricum and F. Esculentum

A promising way to increase the use of buckwheat is the wider introduction of technologies for its processing, including grinding of non-hulled grain. It requires the search for new plant materials with more suitable characteristics. In this work, the possibilities to use the grain of a new artificial buckwheat species Fagopyrum hybridum for flour production are studied in comparison with two cultivated species F. tataricum and F. esculentum. Some chemical characteristics of F. hybridum flour were evaluated. According to the size of the kernel fragments in different modes of milling within each species the significant differences were identified within F. esculentum and F. hybridum (p <0.001 and p <0.05, respectively); there were no significant differences within F. tataricum (p >0.1). Fragments of the seed hulls of F. tataricum and F. hybridum compared to ones of F. esculentum were distinguished by the absence of pronounced acute angles. For the cultivated species, amino acid compositions of grain protein of the studied samples manifest no strong deviations from earlier published results. The new species F. hybridum has the amino acid composition similar to ones of the both cultivated species with slight superiority in the content of all essential amino acids. So, the content of Cysteine, Tryptophan, Arginine, Lysine, Methionine, Leucine + Isoleucine, Threonine, Histidine and Valine in seeds of F. hybridum was 5.2, 15.0, 25.8, 30.2, 31.2, 36.0, 38.4, 41.1 and 46.2% higher compared to F. tataricum and 11.1, 43.7, 39.2, 3.7, 31.2, 15.2, 14.8, 20.0, 18.9% higher compared to F. esculentum. Using DPPH it was assessed the antioxidant activity (AOA) of whole grain flour of three buckwheat species and decreasing of the AOA during heating up to 100 °C.  After water extraction the AOA was maximal for F. tataricum flour; F. hybridum and F. esculentum manifested similar values with the same decline dynamics during heating. After ethanol extraction the flour of F. hybridum shown higher AOA compared to both cultivated species before temperature treatment (1.3 times) as well as after heating to 100 °C (1.2 times). The results of the analysis of the fractional composition of flour from the whole grain of the three buckwheats shown the fragments of the seed hulls of F. tataricum and F. hybridum compared to ones of F. esculentum were characterized by the absence of pronounced acute angles. Additional experiments are needed to optimize the technology of whole-grain buckwheat flour. But the grain of F. tataricum and F. hybridum looks like more suitable for these purposes than the non-hulled grain of F. esculentum.

Treasure from garden: Bioactive compounds of buckwheat

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An extensive review on diverse bioactive components of buckwheat.

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Versatile beneficial phytochemicals are abundant in buckwheat.

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Buckwheat has a wide range of pharmacological and beneficial health effects.

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Huge research scope on Fagopyrum cymosum to identify the beneficial phytochemicals.

Buckwheat is a gluten-free crop under the family Polygonaceae abundant with beneficial phytochemicals that provide significant health benefits. It is cultivated and adapted in diverse ecological zones all over the world. Recently its popularity is expanding as a nutrient-rich healthy food with low-calories. The bioactive compounds in buckwheat are flavonoids (i.e., rutin, quercetin, orientin, isoorientin, vitexin, and isovitexin), fatty acids, polysaccharides, proteins, and amino acids, iminosugars, dietary fiber, fagopyrins, resistant starch, vitamins, and minerals. Buckwheat possesses high nutritional value due to these bioactive compounds. Additionally, several essential bioactive factors that have long been gaining interest because these compounds are beneficial for healing and preventing several human diseases. The present review demonstrates an overview of the recent researches regarding buckwheat phytochemicals and particularly focusing on the distinct function of bioactive components with their health benefits.

Encapsulation of tartary buckwheat flavonoids and application to yoghurt

Aims: The present work investigates the effect of tartary buckwheat flavonoid (TBF) capsules on the physical and chemical properties of yoghurt using polymeric whey protein (PWP) as a wall material.Methods: PWP was prepared by thermal polymerisation. TBF was encapsulated using PWP as the wall material via the pore-coagulation bath method. The physicochemical properties of the TBF capsules, such as the entrapment yield, moisture, average particle size, particle size distribution, surface morphology, molecular interactions, and thermal stability were investigated, in addition to the release of TBF in simulated gastric and intestinal juices. Yoghurt formulation was carried out using encapsulated TBF (3%, w/w), blank PWP beads (2.7%, w/w), and unencapsulated TBF (0.3%, w/w). A control yoghurt sample was prepared without these ingredients. The effects of encapsulated TBF on the chemical composition, acidity, texture, synaeresis, sensory properties, number of Streptococcus thermophilus and Lactobacillus, and other physical and chemical properties of the yoghurt were investigated.Results: TBF capsules were found to be sphere-shaped with porous surfaces, an average particle size of 1728.67 μm, an encapsulation yield of 92.85 ± 1.98% (w/w), and a glass transition temperature of 152.06 °C. When the TBF capsules were exposed to simulated gastric fluid for 4 h, the TBF release rate was 15.75% (w/w), while in simulated intestinal fluid, the TBF release rate reached 65.99% (w/w) after 1 h. After 5-6 h in simulated intestinal fluid, the TBF release rate reached 100% (w/w). The protein content of the yoghurt with encapsulated TBF was 3.57 ± 0.26% (w/w, p < 0.01), and the numbers of Lactobacillus and Streptococcus thermophilus were 2.45 ± 0.98 × 10⁸ (p < 0.01) and 5.43 ± 2.24 × 10⁷ CFU/mL (p < 0.05), respectively, with strong water retention being detected (p < 0.01). Samples containing the encapsulated TBF exhibited a significantly higher acceptability than the unencapsulated TBF (p < 0.01).Conclusions: Encapsulation using PWP effectively delivers TBF to the small intestine through the stomach. It also masks the bitter taste, enhances the colour of TBF-containing yoghurt, and improves the physical and chemical properties of the yoghurt.

Polyphenols and antioxidant activity in pseudocereals and their products

Pseudocereals are important as gluten-free crops that could be utilized as functional foods. They contain proteins with high biological value and also bioactive compounds such as phenolic compounds, flavonoids, vitamins, and minerals that can possess positive health effects on the body. Three types of pseudocereals (amaranth, buckwheat, and quinoa) were evaluated for polyphenols and antioxidant activity. Spectrophotometric methods were used for the determination of free phenols amount with Folin-Ciocalteu reagent, and total antioxidant capacity (TAC) with DPPH and ABTS reagents. Free phenols, the predominant part of polyphenols, were in pseudocereals in the range from 12.4 to 678.1 mg GAE.100g-1. The highest content of FP was found in buckwheat products (146.8 - 678.1 mg GAE.100g-1); quinoa and amaranth products reached much lower values (up to 226.1 mg GAE.100g-1). Antioxidant activity was in an agreement with the FP amounts order, the highest TAC values were again for buckwheat products (167.3 - 473.9 and 876.9 - 3524.8 mg TE.100g-1), followed by quinoa (78.2 - 100.6 and 738.9 - 984.5 mg TE.100g-1) and amaranth ones (25.0 - 69.7 and 118.2 - 431.4 mg TE.100g-1). A high positive correlation between FP amount and TAC values was evaluated for analyzed pseudocereals. The highest content of free phenols and the best antioxidant potential showed buckwheat wholemeal flour, so buckwheat could be characterized as a great source of free phenols with high antioxidant activity.

Carotenoid, Tocopherol, and Phenolic Compound Content and Composition in Cover Crops Used as Forage

Secondary compounds of grassland and forage plant species such as vitamins or phenolic compounds are involved in different health-promoting effects in animals. However, information on their concentration and composition in forage plant species remains scarce. The objective of this study was to characterize the composition of secondary compounds of seven grazed cover crop plant species harvested at two stages of growth. Carotenoids and tocopherols were characterized and quantified using ultraperformance liquid chromatography with a photodiode array, and soluble phenolic compounds were characterized using high-performance liquid chromatography with diode-array detection. All species were rich in carotenoids, especially at the vegetative stage, even if the concentrations varied between plant species. Variations in tocopherol concentrations and phenolic composition were more important between plant species than between stages within species. Among the plant species tested, sainfoin (Onobrychis viciifolia Scop) contained the most secondary metabolites.

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.

Healthy and Resilient Cereals and Pseudo-Cereals for Marginal Agriculture: Molecular Advances for Improving Nutrient Bioavailability

With the ever-increasing world population, an extra 1.5 billion mouths need to be fed by 2050 with continuously dwindling arable land. Hence, it is imperative that extra food come from the marginal lands that are expected to be unsuitable for growing major staple crops under the adverse climate change scenario. Crop diversity provides right alternatives for marginal environments to improve food, feed, and nutritional security. Well-adapted and climate-resilient crops will be the best fit for such a scenario to produce seed and biomass. The minor millets are known for their high nutritional profile and better resilience for several abiotic stresses that make them the suitable crops for arid and salt-affected soils and poor-quality waters. Finger millet (Eleucine coracana) and foxtail millet (Setaria italica), also considered as orphan crops, are highly tolerant grass crop species that grow well in marginal and degraded lands of Africa and Asia with better nutritional profile. Another category of grains, called pseudo-cereals, is considered as rich foods because of their protein quality and content, high mineral content, and healthy and balance food quality. Quinoa (Chenopodium quinoa), amaranth (Amaranthus sp.), and buckwheat (Fagopyrum esculentum) fall under this category. Nevertheless, both minor millets and pseudo-cereals are morphologically different, although similar for micronutrient bioavailability, and their grains are gluten-free. The cultivation of these millets can make dry lands productive and ensure future food as well as nutritional security. Although the natural nutrient profile of these crop plant species is remarkably good, little development has occurred in advances in molecular genetics and breeding efforts to improve the bioavailability of nutrients. Recent advances in NGS have enabled the genome and transcriptome sequencing of these millets and pseudo-cereals for the faster development of molecular markers and application in molecular breeding. Genomic information on finger millet (1,196 Mb with 85,243 genes); S. italica, a model small millet (well-annotated draft genome of 420 Mb with 38,801 protein-coding genes); amaranth (466 Mb genome and 23,059 protein-coding genes); buckwheat (genome size of 1.12 Gb with 35,816 annotated genes); and quinoa (genome size of 1.5 Gb containing 54,438 protein-coding genes) could pave the way for the genetic improvement of these grains. These genomic resources are an important first step toward genetic improvement of these crops. This review highlights the current advances and available resources on genomics to improve nutrient bioavailability in these five suitable crops for the sustained healthy livelihood.

Optimization of Total Phenolic and Flavonoid Contents of Defatted Pitaya (Hylocereus polyrhizus) Seed Extract and Its Antioxidant Properties

The present study was conducted to optimize extraction process for defatted pitaya seed extract (DPSE) adopting response surface methodology (RSM). A five-level central composite design was used to optimize total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), and 2,2′-azino-bis (3-ethylbenzothizoline-6-sulfonic acid (ABTS) activities. The independent variables included extraction time (30–60 min), extraction temperature (40–80 °C) and ethanol concentration (60%–80%). Results showed that the quadratic polynomial equations for all models were significant at (p < 0.05), with non-significant lack of fit at p > 0.05 and R² of more than 0.90. The optimized extraction parameters were established as follows: extraction time of 45 min, extraction temperature of 70 °C and ethanol concentration of 80%. Under these conditions, the recovery of TPC, TFC, and antioxidant activity based on FRAP and ABTS were 128.58 ± 1.61 mg gallic acid equivalent (GAE)/g sample, 9.805 ± 0.69 mg quercetin equivalent (QE)/g sample, 1.23 ± 0.03 mM Fe2+/g sample, and 91.62% ± 0.15, respectively. Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) analysis identified seven chemical compounds with flavonoids constituting major composition of the DPSE.

Pseudocereal grains: Nutritional value, health benefits and current applications for the development of gluten-free foods

Nowadays, consumers are more conscious of the environmental and nutritional benefits of foods. Pseudocereals grains, edible seeds belonging to dicotyledonous plant species, are becoming a current trend in human diets as gluten-free (GF) grains with excellent nutritional and nutraceutical value. Pseudocereals are a good source of starch, fiber, proteins, minerals, vitamins, and phytochemicals such as saponins, polyphenols, phytosterols, phytosteroids, and betalains with potential health benefits. The present review aims to summarize the nutritional quality and phytochemical profile of the three main pseudocereal grains: quinoa, amaranth and buckwheat. In addition, current evidence about their health benefits in animal models and human studies is also provided in detail. Based on the accumulating research supporting the inclusion of pseudocereals grains in the diet of celiac persons, this review discusses the recent advances in their application for the development of new GF products. Future directions for a wider cultivation and commercial exploitation of these crops are also highlighted.

Genome-wide investigation of the heat shock transcription factor (Hsf) gene family in Tartary buckwheat (Fagopyrum tataricum)

Background

Heat shock transcription factor (Hsfs) is widely found in eukaryotes and prokaryotes. Hsfs can not only help organisms resist high temperature, but also participate in the regulation of plant growth and development (such as involved in the regulation of seed maturity and affects the root length of plants). The Hsf gene was first isolated from yeast and then gradually found in plants and sequenced, such as Arabidopsis thaliana, rice, maize. Tartary buckwheat is a rutin-rich crop, and its nutritional value and medicinal value are receiving more and more attention. However, there are few studies on the Hsf genes in Tartary buckwheat. With the whole genome sequence of Tartary buckwheat, we can effectively study the Hsf gene family in Tartary buckwheat.

Results

According to the study, 29 Hsf genes of Tartary buckwheat (FtHsf) were identified and renamed according to location of FtHsf genes on chromosome after removing a redundant gene. Therefore, only 29 FtHsf genes truly had the functional characteristics of the FtHsf family. The 29 FtHsf genes were located on 8 chromosomes of Tartary buckwheat, and we found gene duplication events in the FtHsf gene family, which may promote the expansion of the FtHsf gene family. Then, the motif compositions and the evolutionary relationship of FtHsf proteins and the gene structures, cis-acting elements in the promoter, synteny analysis of FtHsf genes were discussed in detail. What’s more, we found that the transcription levels of FtHsf in different tissues and fruit development stages were significantly different by quantitative real-time PCR (qRT-PCR), implied that FtHsf may differ in function.

Conclusions

In this study, only 29 Hsf genes were identified in Tartary buckwheat. Meanwhile, we also classified the FtHsf genes, and studied their structure, evolutionary relationship and the expression pattern. This series of studies has certain reference value for the study of the specific functional characteristics of Tartary buckwheat Hsf genes and to improve the yield and quality of Tartary buckwheat in the future.

Revisiting the versatile buckwheat: reinvigorating genetic gains through integrated breeding and genomics approach

Emerging insights in buckwheat molecular genetics allow the integration of genomics driven breeding to revive this ancient crop of immense nutraceutical potential from Asia. Out of several thousand known edible plant species, only four crops-rice, wheat, maize and potato provide the largest proportion of daily nutrition to billions of people. While these crops are the primary supplier of carbohydrates, they lack essential amino acids and minerals for a balanced nutrition. The overdependence on only few crops makes the future cropping systems vulnerable to the predicted climate change. Diversifying food resources through incorporation of orphan or minor crops in modern cropping systems is one potential strategy to improve the nutritional security and mitigate the hostile weather patterns. One such crop is buckwheat, which can contribute to the agricultural sustainability as it grows in a wide range of environments, requires relatively low inputs and possess balanced amino acid and micronutrient profiles. Additionally, gluten-free nature of protein and nutraceutical properties of secondary metabolites make the crop a healthy alternative of wheat-based diet in developed countries. Despite enormous potential, efforts for the genetic improvement of buckwheat are considerably lagged behind the conventional cereal crops. With the draft genome sequences in hand, there is a great scope to speed up the progress of genetic improvement of buckwheat. This article outlines the state of the art in buckwheat research and provides concrete perspectives how modern breeding approaches can be implemented to accelerate the genetic gain. Our suggestions are transferable to many minor and underutilized crops to address the issue of limited genetic gain and low productivity.

Analysis of Flavonoid Metabolites in Buckwheat Leaves Using UPLC-ESI-MS/MS

Flavonoids from plants are particularly important in our diet. Buckwheat is a special crop that is rich in flavonoids. In this study, four important buckwheat varieties, including one tartary buckwheat and three common buckwheat varieties, were selected as experimental materials. The total flavonoid content of leaves from red-flowered common buckwheat was the highest, followed by tartary buckwheat leaves. A total of 182 flavonoid metabolites (including 53 flavone, 37 flavonol, 32 flavone C-glycosides, 24 flavanone, 18 anthocyanins, 7 isoflavone, 6 flavonolignan, and 5 proanthocyanidins) were identified based on Ultra Performance Liquid Chromatography–Electrospray Ionization–Tandem Mass Spectrometry (UPLC-ESI-MS/MS) system. Through clustering analysis, principal component analysis (PCA), and orthogonal signal correction and partial least squares-discriminant analysis (OPLS-DA), different samples were clearly separated. Considerable differences were observed in the flavonoid metabolites between tartary buckwheat leaves and common buckwheat leaves, and both displayed unique metabolites with important biological functions. This study provides new insights into the differences of flavonoid metabolites between tartary buckwheat and common buckwheat leaves and provides theoretical basis for the sufficient utilization of buckwheat.

Variations in Accumulation of Lignin and Cellulose and Metabolic Changes in Seed Hull Provide Insight into Dehulling Characteristic of Tartary Buckwheat Seeds

Tartary buckwheat (Fagopyrum tataricum) is considered a profitable crop that possesses medicinal properties, because of its flavonoid compounds. However, the dehulling issue is becoming the bottleneck for consumption of Tartary buckwheat seed. In this study, we investigated the relation between dehulling efficiency and content of lignin and cellulose in the seed hull. Moreover, the untargeted metabolomics analysis, including partial least squares discriminant analysis (PLS-DA) and principal component analysis (PCA), were performed to examine the pattern of metabolic changes in the hull of Tartary buckwheat seeds, XQ 1 and MQ 1, during seed development using gas chromatography mass spectrometry (GC-MS). In mature seed hull the accumulation of highest lignin and lowest cellulose were observed in the hull of MQ 1 seed, a dehulling-friendly variety with highest dehulling efficiency (93%), than that in other dehulling recalcitrant varieties, such as XQ 1 with a range of dehulling efficiency from 2% to 6%. During seed development, the total content of lignin and cellulose increased. MQ 1 and XQ 1 displayed a similar trend in the change of lignin and cellulose that the content was decreased in lignin and increased in cellulose. PCA result showed the metabolic differentiations between MQ 1 and XQ 1 during seed development. The results of our study suggest the compensatory regulation of lignin and cellulose deposition in the hull of mature and developing seed, and deviation of MQ 1 from the ratio of lignin to cellulose of other dehulling recalcitrant varieties may have been a contributing factor that resulted in the dehulling differentia.

Assessment of antioxidant properties of grain concentrate and oxidant-antioxidant status pigs after its inclusion in ration feeding

A grain concentrate was developed for use in bread baking based on whole-ground fermented wheat grain, to enhance that the beneficial properties have fermented wholegrain buckwheat grains in an amount of 20% by weight of the fermented wheat. For the fermentation of grain used dry complex enzyme preparation comprising cellulose, β-glucanase and xylanase (producing Penicillin canescens), dissolved in a buffer based on succinic acid. Under the action of the drug, the micro structure surface of grain was changed. It is established that the character of the change in surface micro structure of wheat and buckwheat grain is the same. The results of the study of the content of vitamin E, flavonoids and antioxidant activity in wheat grains, buckwheat and grain concentrate are obtained by different technologies. The results show that grain concentrates from wheat grain with the addition of 20% buckwheat grains prepared using a solution of enzyme preparation of cellulolytic action in a buffer, based on succinic acid has a high antioxidant activity. As a biological model for studying changes oxidant-antioxidant status of the organism under stress when included in a diet designed grain concentrate, used pigs, that are under stress, caused by weaning them from sows and transportation. Investigated the following parameters oxidant-antioxidant status of the organism pigs: the level of malondialdehyde, ceruloplasmin, vitamins A, E and C in the blood of animals. It is concluded that, to improve the oxidative status of the piglets after weaning period recommended addition of concentrate fodder ration of grain wheat and buckwheat prepared using a solution of an enzyme preparation buffered cellulolytic action on the basis of succinic acid. The developed grain concentrate can be used for making the manufacture of cereal products, including grain bread included in the diet of people who live in conditions of oxidative stress.

Identification and characterization of a rhamnosyltransferase involved in rutin biosynthesis in Fagopyrum esculentum (common buckwheat)

Rutin, a 3-rutinosyl quercetin, is a representative flavonoid distributed in many plant species, and is highlighted for its therapeutic potential. In this study, we purified uridine diphosphate-rhamnose: quercetin 3-O-glucoside 6″-O-rhamnosyltransferase and isolated the corresponding cDNA (FeF3G6″RhaT) from seedlings of common buckwheat (Fagopyrum esculentum). The recombinant FeF3G6″RhaT enzyme expressed in Escherichia coli exhibited 6″-O-rhamnosylation activity against flavonol 3-O-glucoside and flavonol 3-O-galactoside as substrates, but showed only faint activity against flavonoid 7-O-glucosides. Tobacco cells expressing FeF3G6″RhaT converted the administered quercetin into rutin, suggesting that FeF3G6″RhaT can function as a rhamnosyltransferase in planta. Quantitative PCR analysis on several organs of common buckwheat revealed that accumulation of FeF3G6″RhaT began during the early developmental stages of rutin-accumulating organs, such as flowers, leaves, and cotyledons. These results suggest that FeF3G6″RhaT is involved in rutin biosynthesis in common buckwheat.

Insights into the correlation between Physiological changes in and seed development of tartary buckwheat (Fagopyrum tataricum Gaertn.)

BACKGROUND

Tartary buckwheat (Fagopyrum tataricum Gaertn.) is a widely cultivated medicinal and edible crop with excellent economic and nutritional value. The development of tartary buckwheat seeds is a very complex process involving many expression-dependent physiological changes and regulation of a large number of genes and phytohormones. In recent years, the gene regulatory network governing the physiological changes occurring during seed development have received little attention.

RESULTS

Here, we characterized the seed development of tartary buckwheat using light and electron microscopy and measured phytohormone and nutrient accumulation by using high performance liquid chromatography (HPLC) and by profiling the expression of key genes using RNA sequencing with the support of the tartary buckwheat genome. We first divided the development of tartary buckwheat seed into five stages that include complex changes in development, morphology, physiology and phytohormone levels. At the same time, the contents of phytohormones (gibberellin, indole-3-acetic acid, abscisic acid, and zeatin) and nutrients (rutin, starch, total proteins and soluble sugars) at five stages were determined, and their accumulation patterns in the development of tartary buckwheat seeds were analyzed. Second, gene expression patterns of tartary buckwheat samples were compared during three seed developmental stages (13, 19, and 25 days postanthesis, DPA), and 9 765 differentially expressed genes (DEGs) were identified. We analyzed the overlapping DEGs in different sample combinations and measured 665 DEGs in the three samples. Furthermore, expression patterns of DEGs related to phytohormones, flavonoids, starch, and storage proteins were analyzed. Third, we noted the correlation between the trait (physiological changes, nutrient changes) and metabolites during seed development, and discussed the key genes that might be involved in the synthesis and degradation of each of them.

CONCLUSION

We provided abundant genomic resources for tartary buckwheat and Polygonaceae communities and revealed novel molecular insights into the correlations between the physiological changes and seed development of tartary buckwheat.

Lipid-Polymer Hybrid Nanoparticles for Oral Delivery of Tartary Buckwheat Flavonoids

Flavonoids rich in Tartary buckwheat (TBFs) are the acknowledged health-promoting substances, even with the low oral bioavailability due to its chemical instability in gastrointestinal tract and poor intestinal absorption. To obtain the enhanced oral delivery, TBFs, obtained by an environmentally friendly extraction strategy in advance with the amount of 7.66 ± 0.47 mg rutin/g, was incorporated in biocompatible lipid-polymer hybrid nanoparticles (LPNs). Its high encapsulation efficiency of 96.4% ± 1.1%, narrow size distribution of 61.25 ± 1.83 nm with spherical shape, and good storage stability were observed. Compared to free TBFs, TBFs/LPNs exhibited higher antioxidant activity and significant suppression on the pro-inflammatory cytokine secretion in RAW 264.7 macrophage. Moreover, the enhanced delivery of TBFs/LPNs was also embodied in the improved transmembrane transport in Caco-2 monolayer, suggesting its better intestinal absorption, and significantly immune-enhancing efficacy in immunosuppressed mice. These results demonstrated the new perspectives of Tartary buckwheat flavonoids-loaded nanosystem for pharmaceutical and nutraceutical applications.

Global transcriptome analysis and identification of genes involved in nutrients accumulation during seed development of rice tartary buckwheat (Fagopyrum Tararicum)

Tartary buckwheat seeds are rich in various nutrients, such as storage proteins, starch, and flavonoids. To get a good knowledge of the transcriptome dynamics and gene regulatory mechanism during the process of seed development and nutrients accumulation, we performed a comprehensive global transcriptome analysis using rice tartary buckwheat seeds at different development stages, namely pre-filling stage, filling stage, and mature stage. 24 819 expressed genes, including 108 specifically expressed genes, and 11 676 differentially expressed genes (DEGs) were identified. qRT-PCR analysis was performed on 34 DEGs to validate the transcriptome data, and a good consistence was obtained. Based on their expression patterns, the identified DEGs were classified to eight clusters, and the enriched GO items in each cluster were analyzed. In addition, 633 DEGs related to plant hormones were identified. Furthermore, genes in the biosynthesis pathway of nutrients accumulation were analyzed, including 10, 20, and 23 DEGs corresponding to the biosynthesis of seed storage proteins, flavonoids, and starch, respectively. This is the first transcriptome analysis during seed development of tartary buckwheat. It would provide us a comprehensive understanding of the complex transcriptome dynamics during seed development and gene regulatory mechanism of nutrients accumulation.

FT-IR-based method for rutin, quercetin and quercitrin quantification in different buckwheat (Fagopyrum) species

The present study explores an alternative method for antioxidants determination in buckwheat (Fagopyrum) samples. Buckwheat contains different amounts of the antioxidants rutin, quercetin and quercitrin in different plant parts. Buckwheat seeds are most commonly used as food; however, preparations from the herb can also be used as a rich source of rutin. Infrared spectroscopy was used for individual and sum quantification of rutin, quercetin and quercitrin in whole and ground flowers and leaves of seven different buckwheat species. Correlation coefficients R of calibration and independent validation set for rutin, quercetin and quercitrin were 1.00 and 0.98, 0.94 and 0.99, 0.99 and 0.95, respectively. Some of the developed models had accuracy comparable to the reference HPLC method. Additionally many different parameters that give an important insight into the FTIR technique are discussed (different plant parts, whole and ground untreated samples, 3 different resolutions, 7 spectra pre-treatments, using individual or averaged spectra, reducing spectral data input, considering additional non-spectral data). The implemented technique used no sample preparation, is non-destructive and uses very little amounts of sample. Result show that infrared spectroscopy can be a fast and environmentally friendly alternative technique for routine analysis of main flavonoids in aerial parts of buckwheat.

Evaluation of phenolic antioxidant content in organically and conventionally grown buckwheat herb crop and its regrowth

BACKGROUND

Buckwheat herb is known in the pharmaceutical industry as a material rich in phenolics. Buckwheat is also capable of regrowing and producing an additional harvest in the same year. Although buckwheat herb is a popular material, it is not known whether the regrowth has features of the same quality as the first harvest. Therefore, using the herb of 15 varieties of buckwheat cultivated in Lithuania, the present study aimed to examine biometric properties, phenolic content and antioxidant activity as material quality indicators for buckwheat herb and its regrowth under organic and conventional farming conditions.

RESULTS

The highest amount of rutin was indicated in the organically cultivated regrowth of 2015. Buckwheat material accumulated significantly (P < 0.05) lower amounts of other phenolics. A significant correlation between phenolic content and antioxidant activity was observed in the herb and its regrowth in both farming systems.

CONCLUSION

Regrowth was of similar quality to the first harvest in terms of phenolic content and antioxidant activity, although a downward trend in several biometric features was observed: the height of the regrowth plants was up to two-fold smaller and biomass was five- to nine-fold lower compared to that of the first harvest plants. Organic and industrial farming systems were determined to produce plants of similar quality. © 2016 Society of Chemical Industry.

Variety-based research on the phenolic content in the aerial parts of organically and conventionally grown buckwheat

The aim of this study was to evaluate the impact of different farming types-organic and conventional-on phenolic content in buckwheat varieties grown in Lithuania. Rutin was identified as the dominant phenolic compound in contrast to both phenolic acids (chlorogenic and neochlorogenic acids) and other flavonoids (quercetin and quercitrin). It was determined that variety had the highest impact (p<0.05) on the phenolic content of various aerial parts of buckwheat. In most cases, farming practice significantly (p<0.05) affected the accumulation of phenolics in buckwheat. Organically grown plants usually contained higher amounts of phenolics than those grown under conventional farming conditions. According to a cluster analysis, varieties Panda, Zaleika, and VB Nojai were found to accumulate the highest amounts of phenolics.