Amaranth Varieties Research Articles

Anti-Nutrient, Phytochemical and Antiradical Evaluation of 10 Amaranth (Amaranthus spp.) Varieties Before and After Flowering

Amaranth (Amaranthus spp.) vegetable is widely consumed in Kenya and contributes to the alleviation of food insecurity. It is reported to have bioactive components such as antioxidants that help in protecting the body from long-term degenerative diseases. However, amaranth vegetable has also been shown to contain some anti-nutrients such as tannins, phytic acid, oxalates and nitrates which may bind nutrients and reduce their bioavailability in the body. There are many amaranth varieties and there is very little information about differences in the anti-nutrient and phytochemical levels among the varieties. The objective of this study was to determine the phytochemical and anti-nutrient content of ten amaranth varieties at two growth stages, before and after flowering. The study was in Jomo Kenyatta University of Agriculture and Technology. Ten amaranth varieties, eight of which are new varieties, were planted. Harvesting was done in two stages, at vegetative stage and post flowering stage. The leaves were analyzed for nitrates, vitamin C, total carotenoids, flavonoids and total antioxidant activity. Results showed decrease in nitrates which reduced by about 40% as the plants matured. The leaves also increased antioxidant activity as the plants matured with the concentration equivalent (IC50) with DPPH of 2 mg/mL at vegetative stage and about 1mg/mL after flowering. In conclusion, as the plants grow older, there was an increased accumulation of anti-nutrient and other plant chemicals. Antioxidant activity is however increased.

Analysis of genetic diversity in grain amaranth (Amaranthusspp.)

The genetic divergence in 100 genotypes and germplasm lines of grain amaranth (Amaranthus spp.) was assessed by using non-hierarchical Euclidean cluster analysis. The genotypes were grouped into 15 distinct clusters revealing wide diversity in the experimental material. Cluster XV was largest with 18 followed by cluster XIV with 15 and cluster VIII with 11 genotypes, while cluster VI was solitary. Clustering pattern of genotypes showed lack of any relationship between geographic origin and genetic diversity. Intra cluster values ranged from 0.00 to 23.81 and cluster VII was the most diverse group. The inter cluster values ranged from 22.30 to 133.55. Maximum divergence was noticed between clusters VI and XIII (133.55) followed by clusters I and IV (132.74).The diverse clusters derived could be used in hybridization programme to develop high yielding grain amaranth varieties.

Effect of Varied NPK Fertilization on Catalase Activity of Amaranth (Amaranthus Cruentus L.)

Abstract A study was carried out on the effect of varied NPK fertilization on catalase activity per gram fresh weight of the leaves of two varieties of amaranth, Rawa and Aztek, at different developmental stages (seedling, five-leaf, flowering and mature seed), as well as in the seeds. Amaranth was grown in a field experiment in southeast Poland, at wide-row spacing on good wheat complex soil. The following combinations of macronutrient levels were applied: I - 50 kg N ・ ha-1, 40 kg P ・ ha-1, 40 kg K ・ ha-1, II - 70 kg N ・ ha-1, 50 kg P ・ ha-1, 50 kg K ・ ha-1, III - 90 kg N ・ ha-1, 60 kg P ・ ha-1, 60 kg K ・ ha-1 and IV - 130 kg N ・ ha-1, 70 kg P ・ ha-1, 70 kg K ・ ha-1. The study showed that catalase activity exhibited a downward trend during the vegetation period of amaranth. The highest catalase activity was noted in the leaves during the first stage, ie the seedling stage. Increasing levels of NPK led to an increase in catalase activity. Leaves of the Rawa variety had higher catalase activity than those of the Aztek variety at every stage of development. The level of catalase activity in the amaranth seeds was also significantly affected by fertilization and the variety of amaranth. Higher levels of the fertilizers caused an increase in catalase activity in the seeds.

Erratum to: Differences among five amaranth varieties (Amaranthus spp.) regarding secondary metabolites and foliar herbivory by chewing insects in the field

In this study, we determined the abundance of secondary metabolites present in leaves of five varieties of Amaranthus, described the community of chewing insects observed in the foliage and also quantified damage by folivore insects in the field. Three flavonoid glucosides (rutin, nicotiflorin and isoquercitin), nine phenolic compounds (coumaric, vanillic, caffeic, syringic, ferulic, sinapic, protocatechuic, salicylic and 4-hydroxybenzoic acid) and three betalains (amaranthine, iso-amaranthine and betanin) were found to be present in amaranth leaves. Flavonoids appeared in of all varieties analyzed, with rutin being the most important. Betalains occurred only in some varieties and at different proportions, and nine phenolic acids were observed in all the varieties, with the exception of sinapic acid. Significant differences in the chemical composition of the varieties were noted. A total of 17 species of chewing phytophagous insects were observed through visual counting in Amaranthus plants, with the order Coleoptera being the most important and having the highest diversity of species. The degree of herbivory differed significantly among the varieties. Multivariate regression analysis indicated that the eight analyzed compounds detected in the plants had significant linear relationships with herbivory in the field. However, to draw any conclusions relating the amount of any compound to the degree of herbivory damage is premature at this stage of the research.

Iron, zinc and calcium dialyzability from extruded product based on whole grain amaranth (Amaranthus caudatus and Amaranthus cruentus) and amaranth/Zea mays blends

Amaranth is a Native American grain appreciated for its high nutritional properties including high mineral content. The aim of this study was to evaluate the availability of Fe, Zn and Ca from extruded products made with two varieties of amaranth and their mixtures with maize at two levels of replacement. Mineral availability was estimated using dialyzability method. The contents of Fe (64.0–84.0 mg/kg), Ca (1977.5–2348.8 mg/kg) and Zn (30.0–32.1 mg/kg) were higher in amaranth than in maize products (6.2, 19.1, 9.7 mg/kg, respectively). Mineral availability was in the range of (2.0–3.6%), (3.3–11.1%) and (1.6–11.4%) for Fe, Ca and Zn, respectively. Extruded amaranth and amaranth/maize products provide higher amount of Fe and Ca than extruded maize. Extruded amaranth products and amaranth addition to maize could be an interesting way to increase nutritional value of extruded products.

Differences among five amaranth varieties (Amaranthus spp.) regarding secondary metabolites and foliar herbivory by chewing insects in the field

Fil: Niveyro, Selene Leonor. Universidad Nacional de La Pampa. Falcultad de Agronomia; Argentina

Phytoavailability of heavy metals in tidal flat soils after fresh water leaching

The phytoavailability of Cd, Pb, Cr, Zn, Cu, and Ni, retained in tidal flat soil after fresh water leaching during reclamation was investigated. Two salt-tolerant varieties of tomato (Lycopersicon esculentum) and edible amaranth (Amaranthus mangostanus L.) were planted in soils having eight different desalination levels (from 6.7 to 1.4gkg−1 salinity) using pot experiments. Soil leaching significantly decreased the uptake of all metals by crop roots except for Ni. The reduction of soil salinity and exchangeable fraction content of Cd and Pb after leaching contributed to the decrease of uptake of metals by roots. All heavy metal concentrations in the edible parts of both crops in the two lowest salinity level treatments were lower than their maximum allowable levels in food. Results suggest that reclamation of tidal flats can reduce the phytoavailability of the heavy metals retained in soil. But the soil heavy metals may still pose health risks in the cultivation of root food crops.

Assessment of Content of Fat and Tocopherols in Seeds of Amaranthus in Relation to Diversified Fertilization with Macroelements

Assessment of Content of Fat and Tocopherols in Seeds of Amaranthus in Relation to Diversified Fertilization with Macroelements This study is based on the field experiment carried out in the years 2007-2008, on an individual farmer's field in Bodaczow, near Zamosc. The aim of the experiment was to determine the influence of different dosages of NPK on the content of fat and homologous tocopherols in the seeds of two varieties of amaranth: Rawa and Aztek. The experiment was started on brown soil made from loess, with high content of P, K and Mg, and slightly acidic reaction (pH in l mol KCl·dm-3 - 5.8). The experiment was started with split-plot method in three repetitions, and involved: two varieties of amaranthus (Rawa and Aztek), and 4 variants of fertilization with macroelements NPK (kg · ha-1) (1 - object without any fertilization, 2 - 70 N, 50 P2O5, 50 K2O; 3 - 90 N, 60 P2O5, 60 K2O; 4 - 130 N, 70 P2O5, 70 K2O). The content of fat was marked in the seed with Soxhlet's method, and α-, β-, γ- and Δ-tocopherol with high performance liquid chromatography (HPLC). The study reveals that the amount of accumulated fat in the seeds of amaranthus largely depended on the variety of the plant and variant of fertilization with macroelements. Significantly high content of fat in the seeds was found at the fourth (the highest) level of fertilization with NPK. Higher content of fat in the seeds was determined in Aztec variety than Rawa. The varieties of amaranthus varied considerably in the content of: α-, β-tocopherol and their total amount. Higher content of α-tocopherol and its higher total amount was found in the seeds of Aztek variety, rather than Rawa. The seeds of Rawa variety had significantly more β-tocopherol than Aztek variety. Fertilization with growing dosages of NPK had a significant, positive influence only on the amount of α-tocopherol and its total amount.

Antioxidant-Rich Amaranth Varieties, Arka Samraksha and Arka Varna

Amaranth improvement in India hither to was concerned with development of high-yielding varieties, and hardly any research efforts have been made for its nutritional improvement. Keeping this in view, at Indian Institute of Horticultural Research two high-yielding amaranth varieties, Arka Samraksha and Arka Varna with high antioxidant activity, low amounts of nitrates and oxalates were developed using modified bulk method of selection from segregating population of the crosses IIHR-4 x IIHR-70 and IIHR-7 x IIHR-30 . Arka Samraksha is a high-yielding (10.9 t/ha in 30-35 days), pulling-type variety with green leaves and stem, antioxidant activity of 499mg (AEAC units) and minimum nitrate content of 27.3 mg and 1.34 g oxalates per 100 g fresh leaf weight. Arka Varna also a pulling type, high-yielding variety (10.6 t/ha in 30-35 days) with green leaves and a pink stem, high antioxidant activity of 417 mg (AEAC units), low nitrate content of 37.6 mg and 1.42 g oxalates per 100 g fresh leaf weight.

Biochemical and Immunochemical Characterization of Different Varieties of Amaranth (Amaranthus L. ssp.) as a Safe Ingredient for Gluten-free Products

Celiac disease is a food intolerance triggered by the ingestion of gluten-containing cereals; the only therapy is a strict gluten-free diet for life. In recent years, amaranth flour has received considerable attention as an interesting source for the formulation of gluten-free products due to its high nutritional value and low content of prolamins, the toxic proteins for celiacs. The aim of this study was to characterize 40 amaranth varieties using both SDS-PAGE/immunoblotting and ELISA to assess their possible tolerance by celiac subjects. All of the amaranth samples studied showed similar binding affinities for both specific anti-gliadin antibodies and human IgAs. In most amaranth grains, the content of gluten-like proteins measured by ELISA was <20 ppm. The molecular characterization of amaranth proteins suggests that amaranth is safe for celiacs to consume. It is recommended that the most suitable amaranth varieties are those having the lowest content of proteins cross-reacting with anti-gliadin antibodies.

Genetic divergence in grain amaranth (Amaranthus hypochondriacus L.)

Extent and magnitude of genetic divergence for 14 characters among 98 genotypes of grain amaranth (Amaranthus hypochondriacus L.) were determined for the purpose of identifying more diverse parents which are expected to engender maximum variability. Based on genetic divergence D2 statistics, genotypes were grouped into 18 clusters in which cluster I contained maximum number of genotypes (42), Cluster II (11), Cluster III (7), Cluster IV and V (5 in each case) and Cluster VI has 4 genotypes. Cluster VII, VIII, IX, X have (3 in each), cluster XI, XII, XIII, XIV (2 in each) and clusters XV, XVI, XVII and XVIII (1in each case). The clustering pattern revealed that there was no relationship between genetic divergence and eco-geographical region. Intra cluster values ranged from 0.00 to 141.86 and cluster XI is most diverse group. The inter cluster values ranged from 133.08 to 1214.59. Maximum divergence was noticed between clusters VIII and XI (1214.59) followed by clusters XI and XV (982.16) and clusters II and XI (938.89). The diverse clusters derived could be used in hybridization programme to generate wide range of transgressive segregants in population to develop high yielding grain amaranth varieties.

RESIDUAL EFFECTS OF PHOSPHORUS SOURCES IN GRAIN AMARANTH PRODUCTION

Productivity of grain amaranth can be improved at a reduced cost through combined use of low-cost rock phosphate (RP) phosphorus sources as well as selection of amaranth varieties with high phosphorus (P) use efficiencies. Rock phosphate sources are known to exhibit differences with respect to grain yield, disease tolerance and P use efficiency (PUE) in amaranth varieties. However, very little is known about their residual release of P. It is probable that the differential performances exhibited by the RPs might be a function of their P residual properties after cropping. Based on these premises this study was carried out to evaluate the residual effects of P sources under continuous croppings for grain amaranth production. The study was a factorial experiment with four replications. Four P sources: single super phosphate – SSP, ogun rock phosphate – ORP, sokoto rock phosphate – SRP, and control; three amaranth varieties: NH84/493, NH84/445 and NH84/452 were factorially combined with two soil types: Kandiudult and Haplustalf. In order to monitor the residual effects of the P sources the experimental plots were cropped consecutively three times. Results from the study revealed that sandy loam Haplustalf was better than the clayey Kandiudult soil in improving grain amaranth yield under continuous cropping system. Grain yield and relative agronomic efficiency (RAE) decreased with continuous cropping for SSP but increased with continuous cropping for ORP and SRP till second cropping, thereafter there was a decrease. Averaged over the three continuous consecutive croppings, SRP and ORP were 68.9% and 73.5% as effective as SSP in increasing grain yield respectively. It was concluded therefore that ORP and Haplustalf soil are best options for grain amaranth production under continuous cropping system.

Analysis of selected phenolic acids and flavonoids inAmaranthus cruentusandChenopodium quinoaseeds and sprouts by HPLC

Summary Red amaranth (Amaranthus cruentus) and quinoa (Chenopodium quinoa) are pseudocereals with particularly highly regarded nutritional value. Because of the high biological significance of the flavonoids and phenolic acids in these plants, qualitative and quantitative analysis has been performed by HPLC. Extracts from the seeds of two amaranth varieties (A. cruentus v. Rawa and v. Aztek) and quinoa seeds, and their sprouts grown in natural conditions and in the dark were analyzed. The main phenolic acid found both in seeds and sprouts was gallic acid. p-Hydroxybenzoic acid, vanillic acid, p-coumaric acid, caffeic acid, and cinnamic acid were also found in the seeds and p-coumaric acid, syringic acid, and ferulic acid in the sprouts. The main flavonoid found in the sprouts was rutin. Vitexin, isovitexin, and morin were also detected in the sprouts, and orientin, vitexin, isovitexin, morin, and traces of hesperidin and neohesperidin in the seeds. Although sprouting conditions (daylight or darkness) had no effect on gallic acid content, light caused an increase in the amount of rutin and darkness resulted in increased amounts of isovitexin and vitexin.

The content of insoluble fibre and crude protein value of the aboveground biomass of Amaranthus cruentus and A. hypochondriacus

Twenty samples of the aboveground biomass of &lt;i&gt;Amaranthus cruentus&lt;/i&gt; (varieties Olpir, Amar 2 RR-R 150, and A 200 D) and &lt;i&gt;A. hypochondriacus&lt;/i&gt; (variety No. 1008) were analysed to determine their nutritional value during the experimental period covering five growth stages from inflorescence emergence till full ripening of grain. During plant growth, from day 80 to day 120 of cultivation, the nutritional value decreased. This was demonstrated by an increase in insoluble fibre and a reduction in crude protein content. The content of neutral detergent fibre (NDF) in the dry matter increased from 356 to 420 g/kg (&lt;i&gt;P&lt;/i&gt; &lt; 0.01); acid detergent fibre (ADF) from 238 to 286 g/kg (&lt;i&gt;P&lt;/i&gt; &lt; 0.01); acid detergent lignin (ADL) from 22.9 to 53.4 g/kg (&lt;i&gt;P&lt;/i&gt; &lt; 0.01). The content of crude protein in the dry matter of the investigated amaranth varieties decreased from 174 to 109 g/kg (&lt;i&gt;P&lt;/i&gt; &lt; 0.01). In the Czech Republic the aboveground biomass of the cultivated &lt;i&gt;A. cruentus&lt;/i&gt; and &lt;i&gt;A. hypochondriacus&lt;/i&gt; could be used as a good source of fibre and protein in animal diets when harvested in the period from day 80 to 90 of cultivation.

Comparative Effect of Phosphorus Sources for Grain Amaranth Production

Phosphorus (P) is expensive to the sub‐Saharan African resource‐poor farmers; therefore, there is a need for investigation of locally available alternative P sources to enhance farmers' productivity. Optimum P rate was determined during the early and late rains of 1999. Using the optimum P rate, influences of three P sources ogun rock phosphate (ORP), sokoto rock phosphate (SRP), single super phosphate (SSP) and a control were evaluated on amaranth varieties in 2000 at the vegetable research plots of the National Horticultural Research Institute (NIHORT), Ibadan, Nigeria. In 1999, three grain amaranth varieties (NH84/452, NH84/445, and NH84/493) were combined factorially with four P rates: 0, 30, 60, and 90 kgP/ha. Application of P significantly increased plant height, number of branches, leaf dry weight, and grain yield (GY) per plant. Significant increase in GY was in the order NH/493>NH/445>NH/452. Optimum P rates across varieties for leaf dry‐matter yield was established at 51.8 kgP/ha and for grain yield production was 48.4 kgP/ha. The experiment in the following year, 2000, was a RCB design using the optimum P determined in 1999. Three P sources (ORP, SRP, SSP) and a control were factorially combined with the three amaranth varieties. In the 2000 experiment, grain yield was 21.3, 16.9, 16.0, and 7.8 g/plant, respectively, for SSP, SRP, ORP, and the control. Growth was ranked in the order SSP>ORP>SRP>control. It was concluded for fertilizer recommendation purposes that 50 kgP/ha is optimum for grain amaranth production and that amaranth productivity indices could be alternatively improved with indigenous P sources.

Grain yield and protein concentration of two amaranth species ( Amaranthus spp.) as influenced by the nitrogen fertilization

Amaranth, an alternative cereal, is attracting researchers’ attention mainly because of the high nutritional value of its seed, which can be influenced by nitrogen fertilization. The goal of the research carried out on eutric cambisol in Zagreb in the period 2002–2004 was to determine the influence of nitrogen fertilization upon seed yield, seed protein concentration, 1000-seed weight, dry matter content in flowering, plant height and inflorescence length of two grain amaranth varieties belonging to different species: G6 ( Amaranthus cruentus L.) and 1008 ( Amaranthus hypochondriacus L.) grown in the agroecological conditions of north-western Croatia. As nitrogen fertilization is among the most important factors of high yielding of all field crops, knowledge of the grain amaranth nitrogen requirements has an important role for its efficient production. Nitrogen was applied before sowing at the rates of 0, 50 and 100 kg ha −1. Application of 50 and 100 kg N ha −1 led to a significant increase of seed yield and 1000-seed weight compared to the control (without nitrogen fertilization) only in the dry 2003. Seed protein concentration was not affected by nitrogen fertilization. A. hypochondriacus L. gave a higher seed yield while A. cruentus L. had a higher 1000-seed weight. Nitrogen fertilization had no influence on the dry matter content in flowering and plant height. Responses of tested species to weather conditions differed with respect to the said agronomic traits. In the years with higher precipitation A. cruentus L. had a higher dry matter content, while a significantly higher dry matter content in flowering was recorded for A. hypochondriacus L. in the dry 2003. In all the three trial years, A. cruentus L. achieved greater plant height and inflorescence length, but the difference was statistically significant only for plant height in 2002. Positive correlations were recorded between plant height and inflorescence length as well as between inflorescence length and seed yield.

Chemical Composition of the Above-ground Biomass of Amaranthus cruentus and A. hypochondriacus

Forty samples of dry above-ground biomass of two species and four varieties of Amaranthus cruentus (varieties Olpir, Amar 2 RR-R 150, and A 200 D) and A. hypochondriacus (variety No. 1008) were analyzed to determine their nutritional value during the experimental period covering five growth stages since inflorescence emergence till full ripening of grain from day 80 to day 120 of cultivation. The content of crude protein in the investigated amaranth varieties significantly decreased (from 158.2 ± 1.20 - 185.4 ± 2.33 to 103.8 ± 1.20 - 113.1 ± 0.01 g/kg) as well as did the crude ash content (from 169.9 ± 0.14 - 192.2 ± 0.42 to 129.7 ± 0.14 - 138.4 ± 0.21 g/kg). In contrast, the ether extract content significantly increased (from 12.2 ± 0.14 - 15.9 ± 0.28 to 28.0 ± 0.28 - 36.4 ± 0.14 g/kg) as well as crude fibre (from 144.9 ± 2.12 - 170.0 ± 3.68 to 183.6 ± 7.00 - 276.0 ± 1.20 g/kg), and gross-energy (from 16.6 ± 0.03 - 17.2 ± 0.07 to 18.1 ± 0.14 - 18.4 ± 0.01 MJ/kg) between days 80 and 120 of cultivation. The relatively high content of crude protein in the aboveground biomass in the period between days 80 and 90 of cultivation suggests that the plants could be used as a nutrient substitute for conventional forages.

Amino acid contents and biological value of protein in various amaranth species

Amino acid content before and after heat treatment was assessed in grain of six selected amaranth varieties and four species: Amaranthus cruentus, A. hypochondriacus, A. caudatus and A. hybridus, cultivated in the Czech Republic. High content of Lys and Arg was detected in both heat treated and untreated grains, as well as satisfactory content of Cys and lower levels of Met, Val, Ile and Leu. The latter three amino acids appear as limiting. Chemical scores of essential amino acids and essential amino acid index (EAAI) were determined. EAAI value of 90.4% shows the favourable nutritional quality of amaranth protein, which is almost comparable with egg protein. Heat treatment by popping at 170 to 190&amp;deg;C for 30 s resulted in decreased EAAI to 85.4%. Of the essential amino acids under study, Val and Leu contents decreased significantly (P &amp;lt; 0.05). The relatively high content of essential amino acids in amaranth grain predetermines its use as a substitution of meat-and-bone meals. &amp;nbsp;

Analysis of simultaneous water absorption and water–starch reaction during soaking of amaranth grain

The soaking process of a grain amaranth variety ( Amaranthus cruentus) was investigated in water between 30 and 90 °C. A mathematical model describing simultaneous unsteady water diffusion and first-order irreversible water–starch reaction is proposed to simulate soaking process of grains. The observed water absorption curves are used to estimate the effective diffusivities ( D ef) and reaction rate ( k). The values of D ef and k were between 10 −12 and 10 −11 m 2 s −1 and 10 −5 and 10 −3 s −1, respectively. The dependence on temperature of D ef and k was evaluated through an Arrhenius type equation with two distinct activation energies for diffusion ( E D) and reaction ( E k) below and above 64 °C. The calculated values were E D = 31.0 kJ mol −1 and E k = 24.5 kJ mol −1 below 64 °C and E D = 53.6 kJ mol −1 and E k = 136.5 kJ mol −1 above 64 °C. These results suggest that at least, for the soaking temperatures above 64 °C, the absorption process is controlled by water–starch reactivity.

Amaranth as a rich dietary source of beta-sitosterol and other phytosterols.

The analysis of 4 commonly available amaranth varieties (Amaranthus K343, RRC1011, K433, K432) revealed the presence of all three major phytosterols (beta-sitosterol, campesterol, stigmas-terol) with a total sterol content being several fold higher than those found in other studied plants. Substantial differences in total phytosterol content and beta-sitosterol content were found between the amaranth varieties. The most commonly cultivated amaranth variety in the United States, i.e., Amaranthus K343 was found to possess the highest levels of phytosterols of the varieties tested. The possibility of screening for superior amaranth varieties with various health properties is outlined.