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1.
Food Chem ; 308: 125601, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31670190

RESUMO

The aim of this work was to analyse the hypotensive effect of amaranth protein/peptides on spontaneously hypertensive rats (SHR). The mechanism of action of these peptides was studied in vivo and ex vivo. We also tested the effect of protection against gastrointestinal digestion (GID) exerted by an O:W emulsion on the integrity of the antihypertensive peptides. All samples tested produced a decrease in blood pressure (SBP). The animals treated with emulsion (GE) and emulsion + peptide (GE+VIKP) showed the most significant reduction in the SBP (42 ±â€¯2 mmHg and 35 ±â€¯2 mmHg, respectively). The results presented suggest that after GID, a variety of peptides with biological activities were released or were resistant to this process. These peptides play a role in the regulation of the SBP by acting on plasma ACE, plasma renin and the vascular system. These results support the use of amaranth protein/peptides in the elaboration of functional foods for hypertensive individuals.


Assuntos
Amaranthus/química , Anti-Hipertensivos/farmacologia , Hipertensão/tratamento farmacológico , Peptídeos/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Animais , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Masculino , Peptídeos/uso terapêutico , Proteínas de Plantas/farmacologia , Proteínas de Plantas/uso terapêutico , Ratos , Ratos Endogâmicos SHR
2.
J Food Sci ; 84(11): 3075-3082, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31599971

RESUMO

The hypocholesterolemic effect of amaranth was studied in male Wistar rats fed a high-fat diet that was supplemented with amaranth flour, AF, or isolated protein, AI. Likewise, an in vitro test was carried out, in which the capacity of the AI, AF, the digested isolate, DAI, and the digested amaranth flour, DAF, to displace the cholesterol of the model micelles was evaluated. The in vivo results showed an increase in the excretion of cholesterol through feces (77% for AF7; 23% and 108% for AI30 and AF30, respect control) and a decrease in the content of hepatic cholesterol (98% for AF7; 96% and 53% for AI30 and AF30 respect control); whereas in vitro it was shown that both AF and DAF have greater power to displace cholesterol than the AI and DAI (IC50 0.1, 0.71, 0.2, and 2.1 for AF, DAF, AI, and DAI, respectively). These evidences show that the proteins and fibers of amaranth have an effect on cholesterol metabolism. PRACTICAL APPLICATION: Nowadays, consumers give great importance to the effect that food has on health. The results shown in this work evidence the potential hypocholesterolemic activity presented by amaranth, this is of great importance due to the increase in the incidence of dyslipidemia in the world population and the importance of amaranth as a nonextensive crop of excellent agronomic, nutritional, and bioactive properties suitable for preparation of functional foods.


Assuntos
Amaranthus/química , Anticolesterolemiantes/administração & dosagem , Dieta Hiperlipídica , Animais , Anticolesterolemiantes/análise , Colesterol/análise , Colesterol/metabolismo , Colesterol na Dieta , Fezes/química , Fígado/química , Masculino , Ratos , Ratos Wistar
3.
Environ Monit Assess ; 191(9): 569, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31418103

RESUMO

Microcystins (MCs) are toxic secondary metabolites produced by several cyanobacteria genera that have been implicated in human cancer cases and deaths. Human exposure routes include direct contact with contaminated water and the consumption of contaminated food. The present study investigated the presence of MCs in three commonly consumed vegetables at the point of sale in market places as a means of assessing the direct human health risk of buying vegetables. Overall, 53% of the vegetables obtained from different markets had levels of MCs that were higher than 1.00 µg/g. Amaranthus hybridus L. (smooth amaranth) had the highest MC concentration (4.79 µg/g) in samples obtained from Sabon Gari Market, while Lactuca sativa L. (garden lettuce) had the lowest concentration (0.17 µg/g) in samples obtained from Dan-Magaji Market. The highest total daily intake (TDI) of MCs by an adult weighing 60 kg was 3.19 µg/kg for A. hybridus, 1.41 µg/kg for Brassica oleracea L. (cabbage), and 2.94 µg/kg for L. sativa. The highest TDI of MCs for a child weighing 25 kg was highest in A. hybridus (1.91 µg/kg), followed by L. sativa (1.77 µg/kg). These results revealed that the consumption of vegetables sold in markets in Zaria, Nigeria, during the dry season represents a major exposure route to MCs. There is, therefore, an urgent need to develop policies and monitoring strategies to tackle this problem in developing countries.


Assuntos
Amaranthus/química , Brassica/química , Contaminação de Alimentos/análise , Alface/química , Microcistinas/análise , Humanos , Nigéria
4.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438557

RESUMO

Amaranthus hypochondriacus spp. is a commonly grown cereal in Latin America, known for its high protein content. The objective of this study was to separate and identify bioactive peptides found in amaranth seeds through enzymatically-assisted hydrolysis using alcalase and flavourzyme. Hydrolysis was carried out for each enzyme separately and compared to two-step continuous process where both enzymes were combined. The biological activity of the resulting three hydrolysates was analyzed, finding, in general, higher bioactive potential of the hydrolysate obtained in a continuous process (combined enzymes). Its fractions were separated by RP-HPLC, and their bioactivity was analyzed. In particular, two fractions showed the highest biological activity as ACE inhibitors with IC50 at 0.158 and 0.134, thrombin inhibitors with IC50 of 167 and 155, and antioxidants in ABTS assay with SC50 at 1.375 and 0.992 mg/L, respectively. Further sequence analysis of the bioactive peptides was carried out using MALDI-TOF, which identified amino acid chains that have not been reported as bioactive so far. Bibliographic survey allowed identification of similarities between peptides reported in amaranth and other proteins. In conclusion, amaranth proteins are a potential source of peptides with multifunctional activity.


Assuntos
Amaranthus/química , Peptídeos/química , Proteínas de Plantas/química , Sementes/química , Endopeptidases/metabolismo , Subtilisinas/metabolismo
5.
J Agric Food Chem ; 67(33): 9241-9253, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31369258

RESUMO

Antiviral compounds targeting viral replicative processes have been studied as an alternative for the control of begomoviruses. Previously, we have reported that the peptide AmPep1 has strong affinity binding to the replication origin sequence of tomato yellow leaf curl virus (TYLCV). In this study, we describe the mechanism of action of this peptide as a novel alternative for control of plant-infecting DNA viruses. When AmPep1 was applied exogenously to tomato and Nicotiana benthamiana plants infected with TYLCV, a decrease in the synthesis of the two viral DNA strands (CS and VS) was observed, with a consequent delay in the development of disease progress in treated plants. The chemical mechanism of action of AmPep1 was deduced using Raman spectroscopy and molecular modeling showing the formation of chemical interactions such as H bonds and electrostatic interactions and the formation of π-π interactions between both biomolecules contributing to tampering with the viral replication.


Assuntos
Amaranthus/química , Antivirais/química , Antivirais/farmacologia , Begomovirus/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , RNA Viral/química , Replicação Viral/efeitos dos fármacos , Begomovirus/química , Begomovirus/genética , Begomovirus/fisiologia , Sequências Repetidas Invertidas/efeitos dos fármacos , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Proteínas de Plantas/química , RNA Viral/genética , Tabaco/virologia
6.
Molecules ; 24(13)2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31269663

RESUMO

This study aimed to obtain a second-generation snack by extrusion from the by-product of rice milling enriched with amaranth. The raw material used was amaranth flour (AF), rice starch (NS) and modified rice starch (MS), which were evaluated by the analysis of substitution degree (SD), differential scanning calorimetry (DSC), viscosity (RVA), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The snacks were expanded by extrusion and microwave oven, as a reference method. The samples were evaluated in hardness (D), expansion index (EI), apparent density (DAP), and protein content (P). Afterward, the optimized samples were evaluated by scanning electron microscopy (SEM) and resistant starch (RS). During the thermal characterization, a clear trend in the decrement in gelatinization temperatures was observed (78.35 to 63.90 °C in NS and MS respectively). The curves obtained in RVA analyses showed typical behavior of native (6.35 Pa.s) and extruded starches (2.88 Pa.s), with a significant decrease in viscosity peak. Through the analysis of FT-IR, the introduction of the functional acetyl group (stretching at a wavelength of 1735 cm-1) was corroborated. Snack samples results showed a maximum hardness in MS, with a value of 121 N, and the NS (100%) presented the highest EI value (1.41). The lowest DAP values were obtained for the MS (0.48 g/cm3, 100%) and AF (0.49 g/cm3, 100%) samples. P increased to a higher concentration of AF. In the optimum formulation, the SEM image showed that the expanded microwave sample increased the porosity and obtained an RS value of 8.2%. The formulation obtained in the present study presents high characteristics to be used in the development of a healthy snack.


Assuntos
Amaranthus/química , Oryza/química , Lanches , Amido/química , Acetilação , Amilose/química , Cor , Cristalização , Dureza , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Temperatura Ambiente , Viscosidade , Difração de Raios X
7.
J Med Food ; 22(10): 976-981, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31211650

RESUMO

Fermentation has shown to be an effective technique in bioactive peptides release. That is why in this study antihypertensive, antithrombotic, and antioxidant activity was evaluated during amaranth proteins fermentation with Lactobacillus casei Shirota and Streptococcus thermophilus 54102 in mono and combined culture. During fermentation an increase of free amine groups was observed, and no statistical differences among monocultures were shown, getting higher concentration in combined culture. This was related to antihypertensive and antioxidant activities, where the highest values were also found in the combined process (45% of angiotensin-converting enzyme inhibition, and 168 µmol Trolox equivalents per liter [TE/L] for 2,2-diphenyl-1-picrylhydrazyl, 268 µmol TE/L for 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid, and 381 µmol Fe2E/L for ferric reducing ability of plasma). On the contrary, antithrombotic activity was not related to free amine groups during fermentation, having the highest bioactivity in different moments in each experiment. L. casei Shirota and S. thermophilus 54102 are strains that are able to release bioactive peptides from amaranth protein, although amaranth is not a common matrix for the development of lactic acid bacteria. In addition, in this study it was observed for the first time that lactic acid strains are able to release bioactive peptides from amaranth protein. In addition, this methodology could be part for the development of fermented beverages, different from fermented milk, to diversify matrix to obtain a novel functional food.


Assuntos
Amaranthus/química , Fermentação , Lactobacillales/metabolismo , Peptídeos/farmacologia , Proteínas de Plantas/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Antioxidantes/farmacologia , Antitrombinas/farmacologia , Ácido Láctico/metabolismo , Lactobacillus casei , Sementes/química , Streptococcus thermophilus
8.
J Sci Food Agric ; 99(11): 5239-5248, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31062366

RESUMO

BACKGROUND: Pseudocereals are nutrient-rich grains with high mineral content but also phytate content. Phytate is a mineral absorption inhibitor. The study's aim was to evaluate phytate degradation during spontaneous fermentation and during Lactobacillus plantarum 299v® fermentation of quinoa, canihua, and amaranth grains and flours. It also aimed to evaluate the accessibility of iron, zinc, and calcium and to estimate their bioavailability before and after the fermentation of flours with starter culture. Lactic acid, pH, phytate, and mineral content were analyzed during fermentation. RESULTS: Higher phytate degradation was found during the fermentation of flours (64-93%) than during that of grains (12-51%). Results suggest that phytate degradation was mainly due to endogenous phytase activity in different pseudocereals rather than the phytase produced by added microorganisms. The addition of Lactobacillus plantarum 299v® resulted in a higher level of lactic acid (76.8-82.4 g kg-1 DM) during fermentation, and a relatively quicker reduction in pH to 4 than in spontaneous fermentation. Mineral accessibility was increased (1.7-4.6-fold) and phytate : mineral molar ratios were reduced (1.5-4.2-fold) in agreement with phytate degradation (1.8-4.2-fold) in fermented flours. The reduced molar ratios were still above the threshold value for the improved estimated mineral bioavailability of mainly iron. CONCLUSION: Fermentation proved to be effective for degrading phytate in pseudocereal flours, but less so in grains. Fermentation with Lactobacillus plantarum 299v® improved mineral accessibility and estimated bioavailability in flours. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Amaranthus/microbiologia , Chenopodium quinoa/microbiologia , Chenopodium/microbiologia , Lactobacillus plantarum/metabolismo , Minerais/análise , Ácido Fítico/metabolismo , Amaranthus/química , Amaranthus/metabolismo , Chenopodium/química , Chenopodium/metabolismo , Chenopodium quinoa/química , Chenopodium quinoa/metabolismo , Grão Comestível/química , Grão Comestível/metabolismo , Grão Comestível/microbiologia , Fermentação , Farinha/análise , Trato Gastrointestinal/metabolismo , Humanos , Minerais/metabolismo , Ácido Fítico/análise
9.
Environ Sci Pollut Res Int ; 26(22): 22147-22158, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31115806

RESUMO

Differences in cellular cadmium (Cd) distribution between Cd-tolerant and Cd-sensitive lines of amaranth (Amaranthus mangostanus L.) may reveal mechanisms involved in Cd tolerance and hyperaccumulation. We compared the cellular distribution and accumulation of Cd in roots, stems, and leaves between a low-Cd accumulating cultivar (Zibeixian, L-Cd) and a high-Cd accumulating cultivar (Tianxingmi, H-Cd) in a hydroponic experimental system. In all treatments, H-Cd grew better than L-Cd and accumulated more Cd. As the Cd concentration increased, the H-Cd plants grew normally and their biomass increased, except in the 60 µM Cd treatment. The biomass of L-Cd decreased with increasing Cd concentrations. The highest Cd concentration in the roots, stems, and leaves of H-Cd was 950 mg/kg, 305 mg/kg, and 205 mg/kg, respectively, compared with 269 mg/kg, 62.9 mg/kg, and 74.8 mg/kg, respectively, in L-Cd. The Cd distribution differed between the two cultivars. Scanning and transmission electron microscopy and energy-dispersive spectrometry analyses showed that Cd was distributed across the entire cross section of H-Cd roots but largely restricted to the epidermal cells and the exodermis of L-Cd roots. The main Cd storage sites were the root apoplast, cell walls, and intercellular spaces in H-Cd and the root epidermal cells and the exodermis in L-Cd. In H-Cd leaves, Cd accumulated mainly in vacuoles of epidermal cells and, at high external Cd concentrations, in the vacuoles of mesophyll cells.


Assuntos
Corante Amaranto/análise , Amaranthus/química , Folhas de Planta/química , Biomassa , Cádmio/análise , Hidroponia/métodos
10.
Ecotoxicol Environ Saf ; 175: 58-65, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30889400

RESUMO

Amaranthus mangostanus L. (amaranth) was hydroponically grown in different concentrations of biochar amended nutrient solution to investigate the mineral elements migration and physiological response of amaranth as affected by biochar. Our results showed that exposure to 26.6 g/L of biochar greatly increased the root and shoot K, Na and Al content, while 2.6 g/L of biochar greatly increased the root Ca and Mg content. The uptake of K and Al notably altered other elements' accumulation in shoots and roots upon the biochar exposure. The ratio of Ca: K in shoots and Mg: K in roots were negatively correlated to the biochar concentrations, while the ratio of Al: Ca and Al: Mg in roots were positively related to the biochar concentrations. The Al: Fe ratio was also polynomial correlated to the concentrations of biochar. The addition of biochar beyond 2.6 g/L resulted in the cell membrane and DNA damages in roots. The activity of SOD and CAT in 6.7 g/L biochar treated roots was significantly elevated as compared to the ones in other biochar treatments and was almost 2-fold of the control. The photosynthetic Fv/Fm intensity and subcellular structure in leaves were also compromised upon exposure to 26.6 g/L biochar. Taken together, biochar could significantly alter the mineral migration in amaranth and physiologically damage in the plants. It is essential to study the effect of biochar within appropriate concentrations on plants prior to wide application in agriculture.


Assuntos
Amaranthus/efeitos dos fármacos , Carvão Vegetal/toxicidade , Minerais/análise , Fotossíntese/efeitos dos fármacos , Amaranthus/química , Transporte Biológico , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos
11.
Medicina (Kaunas) ; 55(3)2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30897829

RESUMO

Background: The first cases of food allergy to amaranth grain have recently been published. This pseudocereal is considered hypoallergenic, and there is scarce information about the allergenic potential of amaranth proteins, either before or after food processing. Objective: To evaluate, in a mouse model of food allergy, the sensitizing and allergenic potential of extruded and non-extruded albumin and globulin fractions from amaranth grains. Materials and Methods: Amaranth (Amaranthus hypochondriacus) flour was obtained and the albumin and globulin fractions isolated. These protein fractions were also obtained after flour extrusion. An intraperitoneal 28-day protocol was carried out to evaluate the sensitizing and allergenic potential of the proteins. The common and rarely allergenic proteins ovalbumin and potato acidic phosphatase were utilized as reference. Specific IgE and IgG antibodies were evaluated for all the proteins tested. Mast cell protease-1 (mMCP-1) responses were evaluated in serum samples collected after intragastric challenges with the proteins of interest. All serological evaluations were carried out using ELISA. Results: Mice were sensitized to the non-extruded albumin fraction from amaranth grains and to ovalbumin (p = 0.0045). The extrusion process of amaranth proteins abrogated the IgE responses triggered under non-extruded conditions (p = 0.0147). mMCP-1 responses were significantly detected in the group of mice sensitized to ovalbumin (p = 0.0138), but not in others. Conclusions: The non-extruded albumin fraction from amaranth has the potential to sensitize BALB/c mice, but this sensitizing potential fails to induce detectable serum levels of the mast cell degranulation marker mMCP-1 after intragastric challenges. Furthermore, the extrusion process abolished the sensitization potential of the amaranth albumins.


Assuntos
Albuminas/isolamento & purificação , Amaranthus/efeitos adversos , Amaranthus/química , Anticorpos Anti-Idiotípicos/sangue , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/imunologia , Globulinas/isolamento & purificação , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Albuminas/efeitos adversos , Animais , Quimases/sangue , Farinha , Manipulação de Alimentos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Ovalbumina/efeitos adversos
12.
Pharm Biol ; 57(1): 140-144, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30905230

RESUMO

CONTEXT: Amaranth and canola oils have been used traditionally. Amaranth has been identified as being of interest because of its outstanding nutritive value. Amaranth oil is a rich source of highly unsaturated fats and so could be a valuable dietary alternative for individuals affected with obesity. Reactive oxygen species (ROS) are postulated to be involved in systemic inflammation and oxidative stress. Activated polymorphonuclear neutrophils (PMNs) generate high amounts of reactive oxygen species. OBJECTIVE: Our study investigates the impact of amaranth and canola oils supplementation on oxidative metabolism in patients with obesity. We hypothesized that, due to its lipid-lowering and antioxidant properties, amaranth and canola oil would protect against oxidative stress. MATERIALS AND METHODS: We tested 19 obese patients [body mass index (BMI) = 41.1 ± 7.8 kg/m2, (mean ± SD)]. The protocol consisted of two stages: a run-in phase of 2 weeks and an experimental stage - canola or amaranth oil supplementation (20 mL/d) with calorie restriction diet for 3 weeks. The neutrophil oxidative burst was expressed by fluorescence intensity (IF). RESULTS: The oxidative burst had increased significantly at the end of treatment in both groups IF: (21.4 ± 11.15 vs. 35.9 ± 20.3; mean ± SD) p < 0.05. The levels of IF were significantly higher in neutrophils of patients who received canola oil (41.05 ± 25.3) compared to those who received amaranth oil (28.4 ± 11.8) p < 0.05. CONCLUSIONS: Canola oil exerts possible effects on oxidative burst activity in neutrophils in vivo conditions.


Assuntos
Amaranthus/química , Neutrófilos/efeitos dos fármacos , Obesidade/sangue , Obesidade/dietoterapia , Óleo de Brassica napus/farmacologia , Adulto , Idoso , Antioxidantes/farmacologia , Brassica napus/química , Suplementos Nutricionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Óleos Vegetais/farmacologia , Explosão Respiratória/efeitos dos fármacos
13.
Nutrients ; 11(3)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866427

RESUMO

For centuries, Amaranthus sp. were used as food, ornamentals, and medication. Molecular mechanisms, explaining the health beneficial properties of amaranth, are not yet understood, but have been attributed to secondary metabolites, such as phenolic compounds. One of the most abundant phenolic compounds in amaranth leaves is 2-caffeoylisocitric acid (C-IA) and regarding food occurrence, C-IA is exclusively found in various amaranth species. In the present study, the anti-inflammatory activity of C-IA, chlorogenic acid, and caffeic acid in LPS-challenged macrophages (RAW 264.7) has been investigated and cellular contents of the caffeic acid derivatives (CADs) were quantified in the cells and media. The CADs were quantified in the cell lysates in nanomolar concentrations, indicating a cellular uptake. Treatment of LPS-challenged RAW 264.7 cells with 10 µM of CADs counteracted the LPS effects and led to significantly lower mRNA and protein levels of inducible nitric oxide synthase, tumor necrosis factor alpha, and interleukin 6, by directly decreasing the translocation of the nuclear factor κB/Rel-like containing protein 65 into the nucleus. This work provides new insights into the molecular mechanisms that attribute to amaranth's anti-inflammatory properties and highlights C-IA's potential as a health-beneficial compound for future research.


Assuntos
Amaranthus/química , Anti-Inflamatórios/farmacologia , Ácidos Cafeicos/farmacologia , Isocitratos/farmacologia , NF-kappa B/metabolismo , Animais , Ácidos Cafeicos/química , Citocinas/metabolismo , Isocitratos/química , Lipopolissacarídeos/efeitos adversos , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
14.
Phytochemistry ; 161: 1-10, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30776591

RESUMO

Amaranthus retroflexus L., an introduced invasive weed in southern Australia, has been associated with acute renal failure and/or mortality in a number of livestock species. While its leaves, flowers and stems are generally reported to contain high levels of nitrogen, few studies have fully characterised the chemical composition of A. retroflexus foliage with respect to mammalian toxicity. We performed extensive metabolic profiling of stems, leaves, roots and inflorescence tissues of A. retroflexus collected from three spatially and/or temporally distinct toxicity outbreaks, and report on the 1) composition of primary and secondary metabolites in methanolic extracts of A. retroflexus tissues using HPLC and HPLC-MS QToF and 2) chemometric analysis of A. retroflexus extracts in relation to the associated toxin(s). All tissues of A. retroflexus possessed an abundance of N-containing metabolites, particularly quaternary ammonium compounds which were identified as betaines, two of which (valine betaine and isoleucine betaine) are rarely encountered in plants. Cytotoxicity to murine fibroblasts was highest in extracts of leaf tissue and was associated with a single, a small modified peptide with high similarity to N-acetyl-L-α-aspartyl-L-alanyl-L-α-aspartyl-L-α-glutamyl-O-(carboxymethyl)-L-tyrosyl-L-leucinamide, a synthetic phosphotyrosyl mimic involved in cell signaling processes. One possible mode of action leading to acute renal failure in grazing livestock by a modified peptide such as this is proposed.


Assuntos
Amaranthus/química , Betaína/toxicidade , Fibroblastos/efeitos dos fármacos , Extratos Vegetais/toxicidade , Animais , Austrália , Betaína/análise , Sobrevivência Celular/efeitos dos fármacos , Gado , Camundongos , Estrutura Molecular , Células NIH 3T3 , Componentes Aéreos da Planta/química , Extratos Vegetais/análise
15.
J Sep Sci ; 42(9): 1676-1685, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30793517

RESUMO

Betacyanin extract of Amaranthus cruentus L. flowers was fractionated by semi-preparative high-speed counter-current chromatography in a highly polar solvent system: propan-1-ol/acetonitrile/(NH4 )2 SO4satd. soln /H2 O (1.0:0.5:1.2:1.0, v/v/v/v) in tail-to-head mode with 76% retention of the stationary phase. The crude extract as well as the fractions containing betacyanins were analyzed by liquid chromatography with tandem mass spectrometry as well as by high-resolution ion-trap time-of-flight mass spectrometry detection technique for the molecular formulae and multi-step fragmentation pattern elucidation. Four betacyanins; namely, amaranthin, betanin, 6'-O-formyl-amaranthin, and 6'-O-malonyl-amaranthin as well as their diastereomeric forms differing in the configuration of the C-15 carbon atom were identified in the fractions. Amaranthin was the dominant pigment in the extract and was additionally analyzed by nuclear magnetic resonance correlation techniques after the counter-current chromatographic and high-performance liquid chromatographic isolation. Betacyanins were highly enriched during a single high-speed counter-current chromatographic step; therefore, the tentative identification of new compounds for the whole Amaranthaceae family, 6'-O-formyl-amaranthin and 6'-O-malonyl-amaranthin was possible. Different elution profiles of the pigments observed in the counter-current chromatographic system in comparison to high-performance liquid chromatography system confirm a complementarity of both the techniques especially in the separation of diastereomeric pairs of betacyanins.


Assuntos
Amaranthus/química , Betacianinas/química , Distribuição Contracorrente/métodos , Extratos Vegetais/química , Flores/química , Estrutura Molecular , Espectrometria de Massas em Tandem
16.
Food Sci Technol Int ; 25(5): 414-428, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30714395

RESUMO

The design and development of gluten-free foods requires a comprehensive understanding of the behavior of the raw materials to attain the same cooking and nutritional quality as gluten-based food. The objective of this study was to determine the optimal hot-air drying conditions for elaboration of cassava flour to be used in a gluten-free pasta formulation. The results showed that the operational conditions to minimize the hot-air drying time (57 min) to produce cassava flour with higher water holding capacity was 57 ℃ at 3 m/s. Then, the optimal formulation for the pasta was found to be cassava (26 g/100 g), amaranth flour (12 g/100 g), and carboxymethyl cellulose (0.23 g/100 g), which maximized the Aw (0.160), moisture content (3.10 g/100 g), hardness (5.02 N), and protein content (9.30 g/100 g), and it is used for the sensorial analysis, which showed that an earthy taste was the main problem with consumer satisfaction.


Assuntos
Dessecação/métodos , Dieta Livre de Glúten , Manihot/química , Amaranthus/química , Doença Celíaca/dietoterapia , Fenômenos Químicos , Comportamento do Consumidor , Proteínas na Dieta/análise , Temperatura Alta , Tubérculos/química , Paladar , Água/análise
17.
Plant Foods Hum Nutr ; 74(1): 107-114, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30635822

RESUMO

Antiproliferative effect of Amaranthus mantegazzianus proteins and peptides released after simulated gastrointestinal digestion (DH% 37.8 ± 3.8) was investigated on human colon cancer cell line HT-29. Inhibition of proliferation of HT-29 cells was exhibited after a 24 h treatment with different concentrations of amaranth protein isolate (API) and the peptides released after digestion (DGS), presenting IC50 values of 1.35 ± 0.12 and 0.30 ± 0.07 mg soluble protein/mL, respectively. Lactate dehydrogenase assay indicated that both samples caused the loss of membrane integrity and cell lysis over HT-29 cells, and DAPI fluorescence microscopies evidenced typical apoptotic features. Moreover, Annexin V-FITC flow cytometry showed a significant increase of early apoptotic and late apoptotic/necrotic HT-29 cells compared to untreated ones, and caspase-3 assay confirmed the apoptosis induction with a 43.0 ± 10.3 and 65.8 ± 12.7% increase of caspase-3 activity produced by a 2 mg/mL treatment of API and DGS, respectively. In conclusion, amaranth peptides successfully released after simulated gastrointestinal digestion would exert a potential antiproliferative activity over HT-29 tumor cells. This effect was linked to the induction of cell necrosis and apoptosis, supporting the idea of using amaranth proteins as a potential food alternative ingredient for functional foods.


Assuntos
Amaranthus/química , Proliferação de Células/efeitos dos fármacos , Alimento Funcional , Peptídeos/farmacologia , Proteínas de Plantas/farmacologia , Apoptose/efeitos dos fármacos , Digestão , Células HT29 , Humanos
18.
Inflammopharmacology ; 27(5): 975-984, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29679184

RESUMO

Amaranthus spinosus has been consumed traditionally to prevent various diseases including abdominal pain. In this study, the phytochemical composition, antioxidant and analgesic activities of an ethyl acetate extract of A. spinosus leaves (ASEA) were evaluated. The ASEA had the highest concentrations of total phenols (462.2 mg GAE/g DW), condensed tannin (5.01 mg CE/g DW) and total flavonoid contents (30.07 mg CE/g DW) compared to the chloroform, n-hexane, n-butanol and water extracts. Similarly, ASEA showed the most effective total antioxidant activity (45.45 µg/mL), DPPH scavenging activity (27.32 µg/mL) and hydrogen peroxide scavenging activity (30.60 µg/mL). ASEA with the doses of 200-600 mg/kg (p.o.) clearly demonstrated antinociceptive effects by reducing acetic acid-induced abdominal contortions with a maximal inhibition of 79.57% at 600 mg/kg and increasing latencies of the hot-plate paw-licking response. The tested doses also significantly (p < 0.001) decreased the reaction time in the formalin test at the neurogenic and inflammatory phases. ASEA contained ten polyphenols with caffeic acid being the predominant polyphenol. Overall, this study gave evidence that A. spinosus is a new antioxidant and analgesic agent, and justified its traditional use for the treatment of pain.


Assuntos
Acetatos/química , Amaranthus/química , Analgésicos/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Polifenóis/farmacologia , Analgésicos/química , Animais , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/química , Flavonoides/farmacologia , Camundongos , Dor/tratamento farmacológico , Fenóis/química , Extratos Vegetais/química , Polifenóis/química
19.
Crit Rev Food Sci Nutr ; 59(12): 1949-1975, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29388805

RESUMO

This review reported an updated survey on the molecular functional properties of bioactive peptides derived from different Latin American ancient grains such as Maize, common Bean, Amaranth, Quinoa and Chia seeds. Seed storage proteins ecrypt in their sequences diverse peptides associated with a wide range of beneficial effects on the human health and the most studied are antihypertensive, anti-cholesterolemic, antioxidant, anti-inflammatory, anticancer, antimicrobial and immunomodulatory properties. Additionally, in the last decades molecular properties have been also used for their characterization to understand their activities and it makes them highly attractive to be incorporated into food formulations and to complement or replace some conventional cereal grains. Due to the nutraceutical effects, today, these seeds are one of the main gastronomic trends of consumption worldwide due to their nutritional benefits and are part of the shopping lists of many people, among them vegetarians, vegans, celiacs or lovers of raw food. These seeds are a legacy of pre-Columbian civilizations reason why in our time they are considered as "Superfoods of the Gods", "The pre-hispanic superfoods of the future" and "The new golden seeds of the XXI century".


Assuntos
Produtos Agrícolas , Suplementos Nutricionais/análise , Grão Comestível/química , Peptídeos/química , Proteínas de Armazenamento de Sementes/análise , Amaranthus/química , Anti-Infecciosos/análise , Anti-Inflamatórios/análise , Anticolesterolemiantes/análise , Anti-Hipertensivos/análise , Antineoplásicos/análise , Antioxidantes/análise , Chenopodium quinoa/química , Humanos , Imunomodulação , América Latina , Sementes/química , Zea mays/química
20.
J Sci Food Agric ; 99(5): 2275-2284, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30324618

RESUMO

BACKGROUND: Amaranthus tricolor is a unique source of betalain (ß-cyanin and ß-xanthin) and a source of natural antioxidants, such as leaf pigments, vitamins, polyphenols and flavonoids in leafy vegetables. It has substantial importance for the food industry, since these compounds detoxify reactive oxygen species in humans and are involved in defense against several diseases. In addition, previous research has shown that salt stress elevates these compounds in many leafy vegetables. Therefore, we evaluated the effect of salinity stress on these compounds. RESULTS: Three selected A. tricolor genotypes were studied under three salinity levels to evaluate the response of these compounds. Genotype, salinity stress and their interactions significantly affected all the traits studied. A significant and remarkable increase in L, a*, b*, chroma, ß-cyanin, ß-xanthin, betalain, total carotenoids, ß-carotene, ascorbic acid, total polyphenolic content, total flavonoid content and total antioxidant capacity were observed under 50 and 100 mmol L-1 NaCl concentrations. Bioactive leaf pigments, ß-carotene, vitamin C, phenolics and flavonoids showed good antioxidant activity due to positive and significant interrelationships with total antioxidant capacity. CONCLUSIONS: Amaranthus tricolor can tolerate salinity stress without compromising the high quality of the final product. Therefore, it could be a promising alternative crop in saline-prone areas around the globe. © 2018 Society of Chemical Industry.


Assuntos
Amaranthus/química , Flavonoides/análise , Pigmentos Biológicos/metabolismo , Folhas de Planta/química , Polifenóis/análise , Verduras/química , Vitaminas/análise , Amaranthus/crescimento & desenvolvimento , Amaranthus/fisiologia , Cor , Flavonoides/metabolismo , Pigmentos Biológicos/análise , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Polifenóis/metabolismo , Estresse Salino , Verduras/crescimento & desenvolvimento , Verduras/fisiologia , Vitaminas/metabolismo
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