Determining the geographical origin of common buckwheat from China by multivariate analysis based on mineral elements, amino acids and vitamins

Agro-Morphological and Molecular Characterization Reveal Deep Insights in Promising Genetic Diversity and Marker-Trait Associations in Fagopyrum esculentum and Fagopyrum tataricum

Characterisation of genetic diversity is critical to adequately exploit the potential of germplasm collections and identify important traits for breeding programs and sustainable crop improvement. Here, we characterised the phenotypic and genetic diversity of a global collection of the two cultivated buckwheat species Fagopyrum esculentum and Fagopyrum tataricum (190 and 51 accessions, respectively) using 37 agro-morphological traits and 24 SSR markers. A wide range of variation was observed in both species for most of the traits analysed. The two species differed significantly in most traits, with traits related to seeds and flowering contributing most to differentiation. The accessions of each species were divided into three major phenoclusters with no clear geographic clustering. At the molecular level, the polymorphic SSR markers were highly informative, with an average polymorphic information content (PIC) of over 0.65 in both species. Genetic diversity, as determined by Nei's expected heterozygosity (He), was high (He = 0.77 and He = 0.66, respectively) and differed significantly between species (p = 0.03) but was homogeneously distributed between regions, confirming the lack of genetic structure as determined by clustering approaches. The weak genetic structure revealed by the phenotypic and SSR data and the low fixation indices in both species suggested frequent seed exchange and extensive cultivation and selection. In addition, 93 and 140 significant (p < 0.05) marker-trait associations (MTAs) were identified in both species using a general linear model and a mixed linear model, most of which explained >20% of the phenotypic variation in associated traits. Core collections of 23 and 13 phenotypically and genetically diverse accessions, respectively, were developed for F. esculentum and F. tataricum. Overall, the data analysed provided deep insights into the agro-morphological and genetic diversity and genetic relationships among F. esculentum and F. tataricum accessions and pointed to future directions for genomics-based breeding programs and germplasm management.

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.

Principal Components and Cluster Analysis of Trace Elements in Buckwheat Flour

Essential trace elements are required at very low quantities in the human body but are essential for various physiological functions. Each trace element has a specific role and a lack of these elements can easily cause a threat to health and can be potentially fatal. In this study, inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) were used to determine the content of trace metal elements Ca, Fe, Cu, Mg, Zn, Se, Mo, Mn, and Cd in buckwheat flour. The content and distribution characteristics of trace metal elements were investigated using principal component and cluster analysis. The principal component analysis yielded a four-factor model that explained 73.64% of the test data; the cumulative contribution of the variance of the 1st and 2nd principal factors amounted to 44.41% and showed that Cu, Mg, Mo, and Cd are the characteristic elements of buckwheat flour. The cluster analysis divided the 28 buckwheat samples into two groups, to some extent, reflecting the genuineness of buckwheat flour. Buckwheat flour is rich in essential trace metal elements and can be used as a source of dietary nutrients for Mg and Mo.

Agronomic and metabolomics analysis of rice-Tartary buckwheat (Fagopyrum tataricum Gaertn) bred by hybridization

Tartary buckwheat (TB) is an edible pseudocereal with good health benefits, but its adhering thick shell and bitter taste inhibit its consumption. In this study, the first hybrid rice-Tartary buckwheat (RTB) variety Mikuqiao18 (M18), bred by the pedigree selection of crossbreeding ‘Miqiao’ (MQ) with ‘Jingqiaomai2’ (JQ2), was selected for an agronomic and metabolomics analysis. Compared with JQ2, M18 demonstrated a significantly lower yield per plant owing to the decreased grain weight and similar full-filling grain number per plant. However, M18 had a similar kernel weight per plant because of the thinner shell. The sense organ test suggested that M18 had higher taste quality regardless of partial replacement of rice through the improvement of preponderant indicators related to cereal taste quality, including lower values of total protein, albumin, glutelin, globulin, pasting temperature, cool paste viscosity, and setback. Meanwhile, M18 contained high levels of flavonoids, including rutin and quercetin, but presented a positive summary appraisal of cooking with 25% rice. Additionally, 92 metabolites were positively identified by GC–MS, including 59 differentially expressed metabolites (DEMs) between M18 and JQ2. Typically, M18 exhibited lower levels of 20 amino acids and higher levels of 6 sugars and 4 polyols. These DEMs might partly explain the superior eating quality of M18. In addition, M18 was abundant in 4-aminobutyric acid, which is beneficial to human health. The current findings offer a theoretical foundation for breeding rice-Tartary buckwheat with high yield and quality and promoting the cultivation and consumption of rice-Tartary buckwheat as a daily functional cereal.

Determining the geographical origin of flaxseed based on stable isotopes, fatty acids and antioxidant capacity

BACKGROUND

Flaxseed is an economically important oilseed crop whose geographic origin is of significant interest to producers and consumers because every region may exhibit particular quality characteristics. The lipid/fatty acid method of determining the geographic origin of flaxseed has not been found to be adequate.

RESULTS

To improve the discrimination rate and the geographical traceability of this crop, the chemical profiles of the flaxseed samples were characterized via lipids/fatty acids, stable isotopes, and antioxidant capacity. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were also performed. A satisfactory discrimination rate of 98.6% was obtained after combining fatty acids, stable isotopes, and antioxidant capacity to trace the origin of flaxseed from five regions in northern China.

CONCLUSION

This study provides an effective method for distinguishing the geographic origin of flaxseed. © 2021 Society of Chemical Industry.

Traceability of the geographical origin of Siraitia grosvenorii based on multielement contents coupled with chemometric techniques

Siraitia grosvenorii (LHG) is widely used as a medicinal and edible material around the world. The objective of this study was to develop an effective method for the authentication of the geographical origin of LHG in its main producing area Guangxi, China, which is identified as Chinese Protected Designation of Origin product, against other producing regions in China. The content of 14 elements (K, Na, Ca, P, Mg, Al, B, Ba, Cu, Fe, Mn, Ni, Zn, and Sr) of 114 LHG samples was determined by inductively coupled plasma optical emission spectrometry. Multivariate analysis was then performed to classify the geographical origin of LHG samples. The contents of multielement display an obvious trend of clustering according to the geographical origin of LHG samples based on radar plot and principal component analysis. Finally, three supervised statistical techniques, including linear discriminant analysis (LDA), k-nearest neighbours (k-NN), and support vector machine (SVM), were applied to develop classification models. Finally, 40 unknown LHG samples were used to evaluate the predictive ability of model and discrimination rate of 100%, 97.5% and 100% were obtained for LDA, k-NN, and SVM, respectively. This study indicated that it is feasible to attribute unknown LHG samples to its geographical origin based on its multielement content coupled with chemometric techniques.

Determining the geographical origin of milk by multivariate analysis based on stable isotope ratios, elements and fatty acids

To construct a reliable discrimination model for determining milk geographical origin, stable isotope ratios including δ¹³C, δ¹⁵N and δ¹⁸O, 51 elements and 35 fatty acids (FAs) in milk samples from Australia, New Zealand and Austria were detected and analyzed. It is found that all of the stable isotope ratios in the milk samples of Australia are the highest, followed by those of the samples from New Zealand and Austria. In addition, 14 elements and 8 FAs show different contents in the samples of different countries at the significance level of P < 0.05. Based on these results, a multivariate model with good robustness and predictive ability for authenticating milk origin (R²X = 0.693, Q² = 0.854) was successfully constructed. Element contents and stable isotope ratios are more reliable variables for milk origin discrimination and Rb, δ¹⁸O, Tl, Ba, Mo, Sr, δ¹⁵N, Cs, As, Eu, C20:4n6, Sc, C13:0, K, Ca and C16:1n7 are the critical markers in the multivariate model for verifying milk origin.

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.

Rapid discrimination of Chinese dry-cured hams based on Tri-step infrared spectroscopy and computer vision technology

The aim of this study was to establish rapid and efficient methods based on a Tri-step infrared spectroscopy (Fourier transform infrared spectroscopy (FT-IR) integrated with second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR)) and computer vision technology to identify and evaluate the quality of three Chinese dry-cured hams (Jinhua, Xuanwei and Rugao hams). 9 dry-cured hams (3 different quality grades of each geographical origin) had similar IR spectra. Nevertheless, they could be further discriminated visually by SD-IR and 2DCOS-IR spectra. All samples can be separated by the computer vision technology incorporated with Principal Component Analysis (PCA) and Cluster analysis (CA). This study not only preliminarily verified the possibility of using Tri-step infrared spectroscopy and computer vision technology to discriminate the geographical origins and quality grades of Chinese dry-cured hams, but also provided prospects of the application of infrared spectroscopy and computer vision technology to authenticate other meat products.

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.