Lysine biosynthesis and nitrogen metabolism in quinoa (Chenopodium quinoa): Study of enzymes and nitrogen-containing compounds

Aspartate kinase (AK, EC 2.7.2.4), homoserine dehydrogenase (HSDH, EC 1.1.1.3) and dihydrodipicolinate synthase (DHDPS, EC 4.2.1.52) were isolated and partially purified from immature Chenopodium quinoa Willd seeds. Enzyme activities were studied in the presence of the aspartate-derived amino acids lysine, threonine and methionine and also the lysine analogue S-2-aminoethyl-L-cysteine (AEC), at 1 mM and 5 mM. The results confirmed the existence of, at least, two AK isoenzymes, one inhibited by lysine and the other inhibited by threonine, the latter being predominant in quinoa seeds. HSDH activity was also shown to be partially inhibited by threonine, whereas some of the activity was resistant to the inhibitory effect, indicating the presence of two isoenzymes, one resistant and another sensitive to threonine inhibition. Only one DHDPS isoenzyme highly sensitive to lysine inhibition was detected. The results suggest that the high concentration of lysine observed in quinoa seeds is possibly due to a combined effect of increased lysine, synthesis and accumulation in the soluble form and/or as protein lysine. Nitrogen assimilation was also investigated and based on nitrate content, nitrate reductase activity, amino acid distribution and ureide content, the leaves were identified as the predominant site of nitrate reduction in this plant species. The amino acid profile analysis in leaves and roots also indicated an important role of soluble glutamine as a nitrogen transporting compound. (c) 2007 Elsevier Masson SAS. All rights reserved.

Combined effect of the essential oil from Chenopodium ambrosioides and antileishmanial drugs on promastigotes of Leishmania amazonensis

To date, there are no vaccines against Leishmania, and chemotherapy remains the mainstay for the control of leishmaniasis. The drugs of choice used for leishmaniasis therapy are significantly toxic, expensive and with a growing frequency of refractory infections. Because of these limitations, a combination therapy is the better hope. This work demonstrates that the essential oil from Chenopodium ambrosioides shows a synergic activity after incubation in conjunction with pentamidine against promastigotes of Leishmania amazonensis. However, an indifferent effect has been found for combinations of meglumine antimoniate or amphotericin B and the essential oil.

Quinoa (Chenopodium quinoa) reaction to herbicide residue in a Brazilian Savannah soil

The quinoa (Chenopodium quinoa Willd.) cultivation, one of the most promising in double cropping with soybeans or maize, depends on weed control. The objective of this work was to evaluate quinoa reaction to herbicide residue in a savannah soil. Six herbicide treatments, trifluralin, pendimethalin, clomazone, imazaquin, trifluralin + imazaquin and control, were applied, prior to summer cultivation of soybean, in a Dark-Red Latosol (typic Haplustox). Soybean cultivar BR 9 Savana was grown and soil samples were collected at 15, 38, 100, 145 and 206 days after treatment and stored at -5ºC. Bioassays were conducted in greenhouse, using quinoa, cultivar Q18. Imazaquin was the most harmful to quinoa seedlings, up to 206 days after application, followed by clomazone 15-38 days after application; trifluralin and pendimethalin had no residual effect. These results suggest that a broad-base screening should be conducted.

Control de Sitophilus zeamais con polvos vegetales de tres especies del género Chenopodium

Se evaluaron polvos vegetales de Chenopodium ambrosioides L., Chenopodium album L. y Chenopodium quinoa Willd. para el control de Sitophilus zeamais Motschulsky, bajo condiciones de laboratorio. Los parámetros evaluados fueron mortalidad y emergencia de insectos adultos, pérdida de peso y germinación de los granos, efecto ovicida y larvicida, fumigación, repelencia y residualidad de los polvos. El diseño experimental fue completamente al azar, con un arreglo factorial y tres repeticiones. La mayor mortalidad de insectos se obtuvo con los polvos de la inflorescencia y la mezcla de hojas y tallos de Chenopodium ambrosioides L., al 2% (p/p) con valores de 69,4% y 67,9% respectivamente. La menor emergencia de adultos se obtuvo con los mismos tratamientos. La pérdida de peso de granos, en todos los tratamientos de C. ambrosioides, no superó el 3%. Para el tratamiento inflorescencia de C. ambrosioides al 2% (p/p), la residualidad de los polvos se mantuvo hasta los 15 días, con una mortalidad de 98,3%. Esta misma especie presentó una mortalidad de huevos y larvas de 100%, además de presentar un efecto fumigante con una mortalidad de adultos de 100%, en todos los tratamientos evaluados. El polvo de C. ambrosioides es repelente para S. zeamais.

Diversidade genética de Chenopodium ambrosioides da região cacaueira da Bahia com base em marcadores RAPD

Chenopodium ambrosioides L., conhecida no Brasil por suas propriedades medicinais e usada principalmente para o controle de verminoses intestinais, é pouco estudada quanto à diversidade genética. O objetivo deste trabalho foi avaliar a diversidade genética de 16 indivíduos de C. ambrosioides, provenientes de diferentes municípios da região cacaueira da Bahia, pela técnica de RAPD (DNA polimórfico amplificado ao acaso). Apenas 6,9% das 216 bandas RAPD amplificadas foram polimórficas e a análise de agrupamento evidenciou que não há formação de grupos por área de coleta. Portanto, há pequena variabilidade entre os materiais e esta variabilidade encontra-se distribuída entre as regiões amostradas.

BIOFILMS BASED ON CANIHUA FLOUR (Chenopodium Pallidicaule): DESIGN AND CHARACTERIZATION

This work aims to (1) produce and characterize the flour obtained from two varieties of canihua, cupi and illpa-inia, and (2) evaluate the ability of these flours to form biofilms. The flours produced contain proteins, starches, lipids, organic substances containing phenol groups, and high percentages of unsaturated fatty acids. Films produced from the illpa variety presented lower water vapor permeability and larger Young’s modulus values than the films formed from the cupi variety. Both films were yellowish and displayed a high light blocking ability (as compared with polyethylene films), which can be attributed to the presence of phenolic compounds. Furthermore, they showed lesser solubility and water permeability than other polysaccharide films, which may be the result of the higher protein (12%–13.8%) and lipid (11%) contents in canihua flours, as well as the formation of a larger number of S–S bonds. On the other hand, these films presented a single vitreous transition temperature at low temperatures (< 0 °C), crystallization of the A and Vh types, and an additional diffraction peak at 2 = 7.5º, ascribed to the presence of essential fatty acids in canihua flour. Canihua flour can form films with adequate properties and shows promise for potential applications in food packaging, because it acts as a good barrier to incident ultraviolet light.

Coat protein and RNAs of Cole latent virus are not present within chloroplasts of Chenopodium quinoa-infected cells

Cole latent virus (CoLV), genus Carlavirus, was studied by electron microscopy and biochemical approaches with respect both to the ultrastructure of the Chenopodium quinoa infected cells and to its association with chloroplasts. The CoLV was observed to be present as scattered particles interspersed with membranous vesicles and ribosomes or as dense masses of virus particles. These virus particles reacted by immunolabelling with a polyclonal antibody to CoLV. Morphologically, chloroplasts, mitochondria and nuclei appeared to be unaltered by virus infection and virus particles were not detected in these organelles. However, virus particle aggregates were frequently associated with the outer membrane of chloroplasts and occasionally with peroxisomes. Chloroplasts were purified by Percoll gradient, and the coat protein and virus-associated RNAs were extracted and analyzed by Western and Northern blots respectively. Coat protein and CoLV-associated RNAs were not detected within this organelle. The results presented in this work indicate that the association CoLV/chloroplasts, observed in the ultrastructural studies, might be a casual event in the host cell, and that the virus does not replicate inside the organelle.

Eficácia de Chenopodium ambrosioides (erva-de-santa-maria) no controle de endoparasitos de Gallus gallus (galinha caipira)

A pesquisa foi desenvolvida no Laboratório de Zoologia da Universidade Federal Rural do Rio de Janeiro e Setor de Parasitologia Animal da Universidade Estadual do Norte Fluminense Darcy Ribeiro, estado do Rio de Janeiro, no período de 2011 a 2012. O objetivo foi testar in vitro e in vivo a eficácia da planta medicinal Chenopodium ambrosioides Linnaeus, 1786 (erva-de-santa-maria), nas formas fitoterápica e homeopática, como meios alternativos para o controle de endoparasitos de Gallus gallus Linnaeus, 1758 (galinha caipira), um sério problema que afeta a criação e desempenho de aves domésticas, ocasionando morte quando muito intenso, retardo de crescimento, redução do índice de conversão alimentar e aumento na suscetibilidade às doenças infecciosas. As metodologias utilizadas foram preconizadas por Coles et al. (1992), creditada pela World Association for the Advancement of Veterinary Parasitology (WAAVP). O ensaio in vitro demonstrou alta taxa de redução na inibição de eclosão de ovos (97,18%), e o ensaio in vivo, elevada taxa na redução da contagem de ovos nas fezes (91,67%). A pesquisa evidenciou a presença dos gêneros Ascaridia (35,00%), Capillaria (30,00%), Heterakis (25,00%) e Strongyloides (10,00%). C. ambrosioides mostrou em certos momentos superioridade frente ao produto tradicional (Thiabendazole/Mebendazole) e índices superiores aos preconizados pelo Ministério da Agricultura do Brasil e Organização Mundial da Saúde como indicativos de eficácia.

Eficácia de Chenopodium ambrosioides (erva-de-santa-maria) no controle de endoparasitos de Coturnix japônica (codorna japonesa)

Resumo:O objetivo foi testar in vitro e in vivo a eficácia da planta medicinal Chenopodium ambrosioidesLinnaeus, 1786 (erva-de-santa-maria), nas formas fitoterápica e homeopática, como meios alternativos para o controle de endoparasitos de Coturnix japonica Temminck & Schlegel, 1849 (codorna japonesa), um sério problema que afeta a criação e desempenho de aves domésticas, ocasionando morte quando muito intenso, retardo de crescimento, redução de índice de conversão alimentar e aumento na suscetibilidade às doenças infecciosas. As metodologias utilizadas foram preconizadas por Coles et al. (1992), creditada pela World Association for the Advancement of Veterinary Parasitology (WAAVP). A pesquisa evidenciou a presença dos gêneros Ascaridiae Eimeria. O ensaio in vitro demonstrou alta taxa de redução na inibição de eclosão de ovos de Ascaridiasp. (100,00%) e significativa taxa de redução na destruição de oocistos de Eimeriasp. (47,06%). O ensaio in vivodemonstrou alta taxa de redução na contagem de ovos de Ascaridiasp. nas fezes (100,00%) e expressiva taxa de redução na contagem de oocistos de Eimeriasp. nas fezes (60,33%). Chenopodium ambrosioides mostrou em certos momentos superioridade frente ao produto tradicional (Thiabendazole/Mebendazole) e índices superiores aos preconizados pelo Ministério da Agricultura do Brasil e Organização Mundial da Saúde como indicativos de eficácia.

Diferenças entre Chenopodium quinoa e a planta daninha Chenopodium album

A experimentação pioneira com Chenopodium quinoa Willd tem demonstrado sua adaptabilidade à produção de grãos no cerrado. Seus frutos, do tipo aquênio, são cilíndricos, achatados e germinam rapidamente na presença de umidade, após a maturação fisiológica. Na fase inicial do seu desenvolvimento, a quinoa pode ser confundida com a planta daninha Chenopodium album, conhecida no Brasil como ançarinha-branca. As diferenças básicas entre as duas espécies se tornam mais visíveis após o florescimento: ramificação profusa, com rácemos axilares e terminais em C. album, em contraste com C. quinoa, na qual as panículas são terminais, à semelhança do sorgo; o pericarpo é claro e contrasta com o preto em C. album. A quinoa BRS Piabiru, primeiro cultivar para o Brasil, apresenta plantas com 190 cm, nas quais a panícula ocupa 45 cm; maturação fisiológica aos 145 dias; resistência ao acamamento; peso de grãos de 2,42 g 1.000-1; rendimento de 2,8 t ha-1; e biomassa total de 6,6 t ha-1. As sementes de C. album são muito pequenas (0,52 g 1.000-1), germinam gradativamente e permanecem no solo por muitos anos, infestando os cultivos. As diferenças no número de cromossomos, impedindo a polinização cruzada entre as duas espécies e as morfológicas, detectadas na experimentação, mostram que estas são distinguíveis e asseguram que a quinoa apresenta características de adaptação ao cultivo comercial, contrapondo-se às características de invasora em C. album.

Índice de agresividad espacial (IAE) de Chenopodium album en el cultivo de algodón para santiago del estero, Argentina

El Índice de Agresividad Espacial (IAE) es un parámetro bioecológico que indica las características de la distribución de malezas. No existen antecedentes sobre el tema en el cultivo de algodón. El objetivo de este trabajo fue determinar el IAE para Chenopodium album (CHEAL) y relacionarlo con las pérdidas de rendimiento. Se trabajó durante la campaña 2007-2008 en el Campo Experimental de la EEA INTA Santiago del Estero, con el cultivar Guazuncho-INTA. Para el cálculo del IAE, se utilizó un modelo que emplea: altura de planta sobresaliente, su biomasa seca y superficie infestada; número de descendientes, biomasa seca y altura media de los mismos. Dentro del cultivo, en 200 m², fueron marcadas 10 áreas de 1 m². Se realizaron análisis estadísticos paramétricos, ANOVA y Tukey (0,05). Los resultados fueron: a) Algodón: peso de parcela medio: 105.000 g; peso por planta: 597 g; el total de plantas: 79,30; altura media: 0,5951 m; rendimiento medio: 2592 kg ha-1 y, b) CHEAL: peso por parcela: 4920 g; nº de plantas por parcela media: 18,7; altura media: 2,72 m; altura de planta madre de maleza: 3,45 m; 187 plantas hijas, medias con 2,40 m de altura y 58 g de biomasa seca, en la parcela de la planta sobresaliente. El rendimiento de algodón fue de 2.329,50 kg ha-1 en el testigo y las pérdidas medias fueron de 89,76%. El IAE obtenido fue de 3,76 (bajo-intermedio) e indica que, en la distribución, actúan numerosas plantas que se desarrollan en torno a una maleza principal. Con un menor IAE, son mayores las pérdidas producidas en el cultivo de algodón.

Quinoa (Chenopodium quinoa, Willd.) as a source of dietary fiber and other functional components

Four varieties of an Andean indigenous crop, quinoa (Chenopodium quinoa Willd.), were evaluated as a source of dietary fiber, phenolic compounds and antioxidant activity. The crops were processed by extrusion-cooking and the final products were analyzed to determine the dietary fiber, total polyphenols, radical scavenging activity, and in vitro digestibility of starch and protein. There were no significant differences in the contents of total dietary fiber between varieties of quinoa. In all cases, the contents of total and insoluble dietary fiber decreased during the extrusion process. At the same time, the content of soluble dietary fiber increased. The content of total phenolic compounds and the radical scavenging activity increased during the extrusion process in the case of all 4 varieties. There were significant differences between the varieties and the content of total polyphenols. The in vitro protein digestibility of quinoa varieties was between 76.3 and 80.5% and the in vitro starch digestibility was between 65.1 and 68.7%. Our study demonstrates that quinoa can be considered a good source of dietary fiber, polyphenols and other antioxidant compounds and that extrusion improves the nutritional value.

Use of cereal bars with quinoa (Chenopodium quinoa W.) to reduce risk factors related to cardiovascular diseases

Quinoa is considered a pseudocereal with proteins of high biological value, carbohydrates of low glycemic index, phytosteroids, and omega-3 and 6 fatty acids that bring benefits to the human health. The purpose of this study was to investigate the effects of quinoa on the biochemical and anthropometric profile and blood pressure in humans, parameters for measuring risk of cardiovascular diseases. Twenty-two 18 to 45-year-old students were treated daily for 30 days with quinoa in the form of a cereal bar. Blood samples were collected before and after 30 days of treatment to determine glycemic and biochemical profile of the group. The results indicated that quinoa had beneficial effects on part of the population studied since the levels of total cholesterol, triglycerides, and LDL-c showed reduction. It can be concluded that the use of quinoa in diet can be considered beneficial in the prevention and treatment of risk factors related to cardiovascular diseases that are among the leading causes of death in today's globalized world. However, further studies are needed to prove the benefits observed.

Genetic diversity and comparison of physicochemical and nutritional characteristics of six quinoa (Chenopodium quinoa willd.) genotypes cultivated in Chile

The present study was focused on the analysis of agronomical, nutritional, physicochemical, and antioxidant properties of six genetically different quinoa (Chenopodium quinoa Willd) genotypes cultivated in three distinctive geographical zones of Chile. Ancovinto and Cancosa genotypes from the northern Altiplano (19 ºS), Cáhuil and Faro from the central region (34 ºS), and Regalona and Villarica from the southern region (39 ºS) are representative of high genetic differentiation among the pooled samples, in particular between Altiplano and the central-southern groups. A Common-Garden Assay at 30 ºS showed significant differences among seed origins in all morphometric parameters and also in yields. Altiplano genotypes had larger panicule length but no seed production. A significant influence of the different quinoa genotypes on chemical composition and functional properties was also observed. Protein concentration ranged from 11.13 to 16.18 g.100 g-1 d.m., while total dietary fiber content ranged from 8.07-12.08 g.100 g-1 d.m., and both were the highest in Villarrica ecotype. An adequate balance of essential amino acids was also observed. Sucrose was the predominant sugar in all genotypes. Antioxidant activity was high in all genotypes, and it was highest in Faro genotype (79.58% inhibition).

The importance of heat against antinutritional factors from Chenopodium quinoa seeds

Chenopodium quinoa seeds have high protein content. The nutritional value of quinoa is superior compared with traditional cereals. Its essential amino acid composition is considered next to the ideal, and its quality matches that of milk proteins. In this study, the seed storage proteins from Chenopodium quinoa were extracted, fractionated, partially purified, and characterized. The structural characterization was performed by Tricine-SDS-PAGE and two-dimensional electrophoresis, and it confirmed the presence of proteins of molecular weight of 30 and 7kDa, probably corresponding to lectins and trypsin inhibitors, respectively. The functional characterization of these proteins evidenced their activity as antinutritional factors due to their in vitro digestibility. Quinoa proteins have an excellent amino acid composition with many essential amino acids. In vitro digestibility evaluation indicated that heat-treated samples showed a more complete digestion than the native state samples. Quinoa seeds can be an important cereal in human diet after adequate heat treatment.