Search Results (72)

Amaranth (Amaranthus spp.) is a multifaceted genus of C4 plants with significant nutritional and agronomic potential, yet it remains underutilized in mainstream agriculture. Despite growing interest in Amaranth, most germplasm studies have used either phenotypic or molecular approaches alone, lacking integration. Multivariate methods have not been systematically applied to identify promising genotypes, and species-specific selection indices for grain Amaranth remain unexplored. To address these gaps, this study comprehensively characterized 84 Amaranth genotypes representing multiple species (A. caudatus, A. cruentus, A. hypochondriacus, A. hybridus, A. spinosus, A. powellii, A. tricolor, and 38 accessions of unknown taxonomic status) using field experiments in a randomized complete block design with three replications and DNA barcoding with chloroplast (psbA-trnH) and nuclear (ITS) markers. Analysis of variance revealed highly significant differences (p < 0.01) among genotypes for all six agronomic traits evaluated, confirming substantial genetic variability with grain yield exhibiting the widest variation (CV = 28.55%), ranging from 0.25 to 125.56 g/plant. High broad-sense heritability estimates (0.79–0.99) coupled with high genetic advance, particularly for grain yield (117.54%), indicated that these traits would respond favorably to selection. Path analysis and stepwise regression identified early flowering, long inflorescences, and heavy seeds as the primary determinants of grain yield, collectively explaining 27% of yield variation. Mahalanobis D² analysis identified nine multivariate outliers with distinct phenotypic profiles, among which G39 emerged as the most promising breeding candidate, combining exceptional yield (90.50 g/plant) with desirable architecture, long inflorescence, and large seeds. Principal component analysis further resolved trait complexes, identifying 11 PC1-selected promising genotypes as donors for plant architecture and three PC2-selected promising genotypes as donors for seed size characteristics. Molecular analysis revealed distinct genetic relationships. A. caudatus (kiwicha) exhibited limited haplotype diversity indicating a narrow genetic base, while A. cruentus and A. hypochondriacus showed broader diversity, with the nuclear ITS network providing clearer resolution than chloroplast markers due to biparental inheritance. Outlier genotypes, including G82, G83, G13, G10, and G39, occupied unique haplotype positions, confirming that their phenotypic distinctiveness corresponds to genuine genetic differentiation. The novelty of this study lies in integrating multivariate biostatistical techniques (heritability, path analysis, Mahalanobis D², PCA, and stepwise regression) with two complementary DNA barcode systems (chloroplast and nuclear) within a single germplasm collection. This integrated approach provides breeders with well-characterized germplasm, validated selection criteria, and prioritized parental materials for Amaranth improvement. Further multi-location and multi-season evaluations are recommended to ensure the stability and adaptability of these promising germplasm accessions. Full article

The term ‘superfoods’ refers to a rapidly expanding group of food products that have gained increasing global interest due to their high nutritional value and association with health-oriented dietary patterns. Many superfoods, particularly grains and seeds, are rich sources of essential minerals, plant protein, dietary fibre, and bioactive compounds, making them valuable components of gluten-free, vegetarian, and vegan diets. The aim of this study was to evaluate the elemental composition of selected superfood grains and seeds and to verify the reliability of manufacturers’ declarations. The analyses confirmed that the investigated samples possess a rich macro- and trace elemental composition, with pronounced differences among product groups. Based on median concentrations, pumpkin and hemp seeds were characterized by generally high levels of Mg, K, P, Fe, Mn, and Zn, whereas chia seeds exhibited notably elevated Ca content. In contrast, quinoa and amaranth showed comparatively lower elemental concentrations. Most of the results obtained for the analysed products are within the permissible deviation from the value declared on the packaging, as specified in the relevant EU regulations. The presence of potentially toxic elements, including Al, Pb, and Cd, was also detected. Cadmium accumulation was of particular concern in flax seeds, where all samples exceeded the limit of quantification and approached permissible levels. Principal component analysis revealed clear clustering patterns, indicating similarities between amaranth and quinoa, as well as between hemp and pumpkin seeds, while chia and flax seeds formed distinct groups. These results highlight both the nutritional potential of superfoods and the necessity for independent verification of their elemental composition. Full article

Pseudocereals are naturally gluten-free crops because they do not contain gluten-forming proteins which are present in other grains. The main pseudocereals used in bakery formulations are buckwheat, amaranth, and quinoa, because they have a balanced nutritional profile including high-quality proteins, dietary fiber, essential minerals, and bioactive compounds with antioxidant, anti-inflammatory, and cardiometabolic health-promoting effects. Due to their high nutritional value, they have increasingly been used as functional ingredients in bakery products, particularly for consumers with celiac disease, gluten intolerance, or those seeking nutritionally enhanced foods. The present paper reviews recent advances on the nutritional, functional, and technological properties of these pseudocereals, focusing on their applications in bakery products. Their influence on dough behavior, product quality, and the nutritional improvement of bread, cakes, biscuits, muffins, and other baked goods is discussed. Also, different aspects of the use of pseudocereals in gluten-free products are presented. Mentions are also made of the fact that the increasing demand for healthier and gluten-free foods highlights the possibility of using pseudocereals as promising ingredients for the development of nutritionally enriched bakery products of acceptable technological and sensory quality. Full article

The global demand for new ingredients and healthier food products is on the rise. Global challenges like rapid population growth, climate change, and emerging pandemics are putting a strain on food security for future generations. This makes it crucial to seek alternatives for producing nutrient-rich foods using more sustainable methods. In this context, proteins are an essential macronutrient for humanity. Plant-based proteins are becoming increasingly popular for the following reasons: their sustainability, as they have a lower environmental impact compared to animal-based proteins, provided they are consumed locally; their nutritional value, since they contain all the essential nutrients when consumed in a varied way and do not contain limiting amino acids; their potential accessibility; and the health benefits they offer. Consequently, the food industry is developing an increasing market of protein concentrates and isolates from plant sources using wet or dry methods. In particular, dry fractionation is expected to play a key role in enhancing food sustainability, as it allows protein enrichment without the use of water or energy-consuming operations. This review provides a detailed description of the application of dry fractionation method to Andean grains, with quinoa, amaranth, and kañiwa as prominent examples. The narrative review covers the essential primary processing and pretreatments, assesses the properties of the resulting fractions, and discusses their applications and future trends. This work aims to promote the development of innovative and sustainable food solutions. Full article

The objective of this study was to evaluate the structural, functional and morphological characterizations of ultrasonic-assisted extraction of crude prolamin from amaranth grain (Amaranthus hypochondriacus L.). A Box–Behnken design of response surface methodology (RSM) was employed to optimize the extraction parameters. The optimal extraction parameters included a solid/solvent ratio of 1:9 (g:mL), with 50% ethanol solution at 75 °C. Regarding the physicochemical characteristics, amaranth crude prolamin (ACP) possessed more orderly secondary structures (the proportions of α-helix and β-sheet were 43.65% and 25.52%, respectively), which is favorable for improving the object-holding capacity, such as higher oil- and water-holding capacity. The higher surface hydrophobicity of ACP was beneficial for self-assembly into microspheres at high ethanol concentrations. In general, ACP had a wider molecular weight distribution, higher zeta-potential and better emulsifying capacity (3.91 g VE/g prolamin). Thus, these results provide useful insight into the applications of amaranth prolamin. Full article

Drought limits plant growth, development and productivity, leading to more than 50% crop loss globally. Drought-induced oxidative stress disturbs the plant’s metabolism; however, plants activate signaling pathways to respond and adapt to drought stress. Although drought response mechanisms are well reported in several crops, these mechanisms are poorly understood in Amaranthus. As a highly nutritious crop, rich in antioxidants with the ability to survive in extreme agro-climatic environments, Amaranthus has the potential to serve as a climate-smart future crop. This review provides evidence of some drought response traits in grain and vegetable Amaranthus species. Grain amaranths are the most tolerant species, mainly through improved osmoregulation, antioxidant capacity, and gene expression. While biomass partitioning, efficient water use, and membrane stability have been reported in both grain and vegetable amaranth, the molecular response of vegetable amaranth remains limited. Thus, future research must focus on integrated biochemical, molecular, and multi-omics applications to screen and identify resilient Amaranthus genotypes under drought for sustainable agriculture. Full article

Grain amaranths are recalcitrant to conventional in vitro plant regeneration by organogenesis de novo or through somatic embryogenesis. Consequently, floral organogenesis by these methods, representing the culminating developmental point in angiosperms, is rarely achieved. In the present study, the manipulation of in vitro flowering was explored as part of a strategy designed to overcome grain amaranth’s regeneration recalcitrance. It led to an efficient and reproducible in vitro protocol in which half-longitudinally dissected zygotic embryos generated fully developed Amaranthus hypochondriacus (Ah) plants. The use of high-irradiance illumination with LED lamps with a 3:1 red–blue irradiance ratio was a critical factor, leading to a 70% rate of early flowering events under flowering-inhibiting long-day photoperiod conditions. Contrariwise, no flowering was induced under LED white lights. All in vitro flowering Ah plants yielded viable seeds. To understand the basic molecular mechanisms of the phenomenon observed, gene expression patterns and principal component analysis of key flowering-related genes were analyzed after cultivation in vitro for 4, 8, and 12 weeks under both lighting regimes. These coded for photoreceptors, photomorphogenetic regulators, embryogenic modulators, and flowering activators/repressors. The results highlighted the upregulation of key flowering-regulatory genes, including CONSTANS, FLOWERING LOCUS T, and LEAFY, together with the downregulation of the floral repressor TERMINAL FLOWER1. Ribosome biogenesis- and seed-development-related genes were also differentially expressed, supporting a key role in this process for protein synthesis and embryogenesis. A model is proposed to explain how this light-regulated molecular framework enables in vitro flowering and seed production in Ah plants kept under long-day photoperiods. Full article

Currently, there is an increasing demand for plant-based and low-fat snacks. Non-conventional starch and grains are alternative ingredients. Environmentally friendly processing, such as liquid nitrogen and microwaves, can be used to obtain modified starch, as well as hot air frying to cook snacks. The aim of this work was to evaluate the impact of eco-friendly physical modification of starch from Oxalis tuberosa in a low-fat snack processed by hot air frying. First, native starch (NS) was treated with liquid nitrogen (LNS) and liquid nitrogen/microwaves (LNMS), and the amylose/amylopectin content and functional properties were determined. The snacks were formulated with NS or modified starches, amaranth flour, quinoa flour, corn, onion powder, salt, and water; the ingredients were mixed and placed in an electric pasta maker and cooked by hot air frying. The hardness, hedonic test, colorimetric parameters, acrylamide, proximal composition, and fatty acid profile were analyzed. All starches showed similar values of amylose and amylopectin content. LNMS starch had the lowest water solubility index as compared to NS and LNS. The snacks with the starch modified with liquid nitrogen showed the highest values of hardness as well as the highest score for the texture from a hedonic test. The snacks with modified starches showed a lower browning index than the snack formulated with NS. Acrylamide was not detected in any snacks. The lipid value of the snacks with modified starch was 1.9–2.70 g/100 g of sample, providing ω-9, ω-6, and ω-3 fatty acids. All snacks contained 7.7 g of protein/100 g of sample. These low-fat and plant-based snacks are a healthy option made by environmentally friendly technologies. Full article

In this study, the seeking behaviour and food acceptance of larvae of Plodia interpunctella Hübner (Lepidoptera: Pyralidae) were analysed under laboratory conditions. Larval orientation and feeding preferences were assessed using a selection arena for neonate larvae and a four-way olfactometer for third-instar larvae. Stimulants included amaranth bars with additives (honey and chocolate) and natural amaranth (toasted grain only). The results showed that amaranth volatiles influence the orientation and feeding behaviour of this polyphagous insect. A marked preference for sugar-rich foods was observed, with amaranth with honey and amaranth with chocolate being the food sources most frequently chosen by the neonate larvae. These individuals exhibited a gregarious feeding behaviour and did not engage in cannibalism. The third-instar larvae also showed a preference for sweet food but were more attracted to the amaranth–additive combination. In the four-way olfactometer bioassays, chocolate was the most frequently chosen stimulus, while cellophane did not differ significantly from air. An analysis of volatile compounds by gas chromatography mass spectrometry (GC-MS) revealed that amaranth with chocolate releases more volatile compounds (16) compared with honey (12) and natural amaranth (6), suggesting that these volatiles could possibly influence the larvae’s choice of food source. Full article

Ancient grains, including wild rice, millet, fonio, teff, quinoa, amaranth, and sorghum, are re-emerging as vital components of modern diets due to their dense nutritional profiles and diverse health-promoting bioactive compounds. Rich in high-quality proteins, dietary fiber, essential micronutrients, and a broad spectrum of bioactive compounds such as phenolic acids, flavonoids, carotenoids, phytosterols, and betalains, these grains exhibit antioxidant, anti-inflammatory, antidiabetic, cardioprotective, and immunomodulatory properties. Their health-promoting effects are underpinned by multiple interconnected mechanisms, including the reduction in oxidative stress, modulation of inflammatory pathways, regulation of glucose and lipid metabolism, support for mitochondrial function, and enhancement of gut microbiota composition. This review provides a comprehensive synthesis of the essential nutrients, phytochemicals, and functional properties of ancient grains, with particular emphasis on the nutritional and molecular mechanisms through which they contribute to the prevention and management of chronic diseases such as cardiovascular disease, type 2 diabetes, obesity, and metabolic syndrome. Additionally, it highlights the growing application of ancient grains in functional foods and nutrition-sensitive dietary strategies, alongside the technological, agronomic, and consumer-related challenges limiting their broader adoption. Future research priorities include well-designed human clinical trials, standardization of compositional data, innovations in processing for nutrient retention, and sustainable cultivation to fully harness the health, environmental, and cultural benefits of ancient grains within global food systems. Full article

This review is dedicated to exploring recent advancements in the study of amaranth grain and presents research primarily on Amaranthus species such as Amaranthus cruentus, Amaranthus hypochondriacus, and Amaranthus caudatus, and to a lesser extent Amaranthus hybridus, Amaranthus mantegazzianus, Amaranthus muricatus, Amaranthus tuberculatus, Amaranthus viridis, Amaranthus spinosus, and Amaranthus tenuifoliu. Amaranth (Amaranthus spp.) is a promising, high-yield pseudocereal crop with significant commercial potential for developing functional food products. It contains a wide range of bioactive compounds, including squalene, tocopherols, phenolic compounds, phytates, and vitamins, which possess important physiological properties. Amaranth grain is characterized by high levels of starch, proteins, minerals, and dietary fiber. Moreover, amaranth proteins are distinguished by a balanced amino acid composition and exhibit greater resistance to external factors compared to animal-derived proteins. Grains of amaranth are free of gliadin, making it a valuable nutritional source for individuals with celiac disease, an immune-mediated disorder. Unlike traditional cereals, where prolamins and glutelins dominate the protein composition, the proteins of pseudocereals like amaranth primarily consist of albumins and globulins. The processing methods of amaranth grain influence their quantitative and qualitative composition, often significantly improving their physicochemical, antioxidant, functional, and rheological properties. This work provides a detailed analysis of amaranth’s chemical composition and bioactive components, along with its evaluation of therapeutic and preventive properties. Amaranth protein fractions (albumin, globulin, and glutelin) and squalene exhibit increased antioxidant activity, contributing to notable resistance to radiation and X-ray exposure. Bioactive compounds such as phytol, α-tocopherol, and a lunasin-like peptide (AhLun) with potential anticancer properties have also been identified in amaranth. Furthermore, six bioactive peptides were isolated and identified from amaranth, which, according to predictive models, demonstrate a high capacity to inhibit angiotensin-converting enzyme (ACE) activity, suggesting potential hypotensive effects. Certain amaranth peptides are considered promising functional food ingredients for the prevention and comprehensive treatment of conditions such as diabetes, inflammatory bowel diseases, hypercholesterolemia, cardiovascular diseases, and obesity. Amaranthus spp. and its processed products hold significant interest for the development of innovative food products, contributing to the expansion of their range and enhancement of nutritional value. Full article

Protease inhibitors are biomolecules with growing biotechnological and biomedical relevance, including those derived from plants. This study investigated strong trypsin inhibitors in quinoa, amaranth, and lupine seeds, plant grains traditionally used in Andean South America. Amaranth seeds displayed the highest trypsin inhibitory activity, despite having the lowest content of aqueous soluble and thermostable protein material. This activity, directly identified by enzymatic assay, HPLC, intensity-fading mass spectrometry (IF-MS), and MS/MS, was attributed to a single protein of 7889.1 Da, identified as identical in Amaranthus caudatus and A. hybridus, with a K_i of 1.2 nM for the canonical bovine trypsin. This form of the inhibitor, which is highly homogeneous and scalable, was selected, purified, and structurally–functionally characterized due to the high nutritional quality of amaranth seeds as well as its promising agriculture–biotech–biomed applicability. The protein was crystallized in complex with bovine trypsin, and its 3D crystal structure resolved at 2.85 Å, revealing a substrate-like transition state interaction. This verified its classification within the potato I inhibitor family. It also evidenced that the single disulfide bond of the inhibitor constrains its binding loop, which is a key feature. Cell culture assays showed that the inhibitor did not affect the growth of distinct plant microbial pathogen models, including diverse bacteria, fungi, and parasite models, such as Mycoplasma genitalium and Plasmodium falciparum. These findings disfavour the notion that the inhibitor plays an antimicrobial role, favouring its potential as an agricultural insect deterrent and prompting a redirection of its functional research. Full article

Protein and minerals are central to human diets. This study investigated the effects of germination periods (24 h, 48 h, and 72 h) as a pretreatment process on the nutritional and antinutritional components of pearl millet and amaranth grain flours (28 ± 0.1 °C). The results showed significant differences (p < 0.05) in the proximate, mineral, and antinutrient factors of the samples. The highest protein content, 8.61% in the millet and 17.37% in the amaranth, was observed after 24 h of germination. Specifically, the protein content in the millet after 24 h of germination, 8.61%, was significantly higher than after 72 h, which was 8.07%, and also higher than in the ungerminated millet flour, which was 7.71%. Furthermore, the concentration of iron (Fe) in the millet after 24 h, 48 h, and 72 h of germination was 4.77 mg/100 g, 4.90 mg/100 g, and 4.96 mg/100 g, while in the amaranth; they were 4.10 mg/100 g, 5.86 mg/100 g, and 5.89 mg/100 g. The iron concentration in the ungerminated millet flour, 3.31 mg/100 g, was significantly lower than what was observed in the germinated millet across the periods. A similar trend was observed in the amaranth. In terms of antinutrients, a notable reduction in their concentration was observed as the germination periods increased. The concentration of phytates in the millet ranged from 0.173 g to 0.836/100 g. However, the phytate concentration significantly decreased from 0.836 g/100 g in the ungerminated millet flour to 0.326 g/100 g, 0.230 g/100 g, and 0.173 g/100 g after 24 h, 48 h, and 72 h of germination, respectively. This study shows the potential influence of germination periods on the quality of grains such as millet and amaranth. Full article

The present work aimed to investigate the effect of increasing CO₂ concentration on the growth, productivity, grain quality, and biochemical changes in quinoa and amaranth plants. An experiment was conducted in open chambers (OTCs) to evaluate the responses of these species to different levels of CO₂ {a[CO₂] = 400 ± 50 μmol mol⁻¹ CO₂ for ambient CO₂ concentration, e[CO₂] = 700 ± 50 μmol mol⁻¹ CO₂ for the elevated CO₂ concentration}. Growth parameters and photosynthetic pigments reflected changes in gas exchange, saccharolytic enzymes, and carbohydrate metabolism when plants were grown under e[CO₂]. Furthermore, both species maintained most of the parameters related to gas exchange, demonstrating that the antioxidant system was efficient in supporting the primary metabolism of plants under e[CO₂] conditions. Both species were taller and had longer roots and a greater dry weight of roots and shoots when under e[CO₂]. On the other hand, the panicle was shorter under the same situation, indicating that the plants invested energy, nutrients, and all mechanisms in their growth to mitigate stress in expense of yield. This led to a reduction on panicle size and, ultimately, reducing quinoa grain yield. Although e[CO₂] altered the plant’s metabolic parameters for amaranth, the plants managed to maintain their development without affecting grain yield. Protein levels in grains were reduced in both species under e[CO₂] in the average of two harvests. Therefore, for amaranth, the increase in CO₂ mainly contributes to lowering the protein content of the grains. As for quinoa, its yield performance is also affected, in addition to its protein content. These findings provide new insights into how plants C3 (amaranth) and C4 (quinoa) respond to e[CO₂], significantly increasing photosynthesis and its growth but ultimately reducing yield for quinoa and protein content in both species. This result ultimately underscore the critical need to breed plants that can adapt to e[CO₂] as means to mitigate its negative effects and to ensure sustainable and nutritious crop production in future environmental conditions. Full article

The adoption of grain amaranth (Amaranthus hypochondriacus L.) as a climate-smart crop due to its hardiness and drought escape mechanisms in sub-Saharan Africa is under threat from the lack of pure seed due to contamination by weedy relatives, such as pigweed (A. hybridus L.). Due to limited land availability, proper isolation distances to attain seed purity in the small-scale farming sector are impossible. A study investigating the cross-pollination rate between grain amaranth and pigweed at distances between 3 and 150 m was conducted at three sites in Zimbabwe during the 2020/2021 and 2021/2022 rainy seasons. Grain amaranth was planted at radial distances of 3 to 150 m from the pure pigweed plot. Meteorological conditions, such as temperature and wind speed and direction, were measured during the anthesis period. The cross-pollination rate in grain amaranth was influenced by distance from the pollen source. A maximum cross-pollination rate of 12.9% was observed within a 10 m radius from the pollen donor plot, and a minimum outcrossing rate of 0.45% was recorded at 150 m. The complete removal of weedy relatives within an extrapolated distance of 325 m is recommended to maintain the genetic purity of grain amaranth in small-scale farming systems. Full article