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1.
ScientificWorldJournal ; 2022: 7664321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35514608

RESUMO

Grapevine (Vitis vinifera L.) is a plant containing many phenolic compounds, mostly distributed in the peel, pulp, and seeds. This study evaluates the centesimal composition and bioactive compounds in Shiraz grape (Vitis vinifera) peels using spectrophotometric and UHPLC techniques and develops different formulations of compound powders from the peels and arrowroot using conventional drying technology. The results demonstrate that Shiraz grape skin contains significant amounts of insoluble fiber (15.3%), phenolics (157.09 ± 6.96-149.11 ± 9.27 mg GAE g-1), and flavonoids (0.75 ± 0.50-2.00 ± 0.50 mg QE g-1), with excellent antioxidant capacity observed in the alcoholic extracts. The phenolic content in the developed powdered compounds ranged from 128.32 to 139.70 mg GAE g-1. In general, the compounds showed good antioxidant capacity (IC50 = 0.17 to 0.19 µg mL-1). According to the chromatographic evaluation, it was possible to quantify gallic acid, catechin, and epicatechin, the latter of which was found in the largest quantities in the six formulations. The EV5 formulation was the most efficient in terms of phenolic compounds and protein amounts. This formulation's composition and low cost could make it viable for use in the food industry.


Assuntos
Catequina , Marantaceae , Vitis , Antioxidantes/química , Catequina/análise , Grão Comestível/química , Flavonoides/química , Fenóis/química , Extratos Vegetais/química , Pós , Vitis/química
2.
Int J Biol Macromol ; 182: 1618-1627, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34052266

RESUMO

The goal of this paper was to evaluate the influence of a range of plasma generation voltages on the physicochemical, structural, and technological properties of Aria (Goeppertia allouia) starch. Untreated (0 kV) and high voltages of cold plasma generation (7, 10, 14, and 20 kV) treated samples were evaluated according to their amylose content, pH, groups carbonyl/carboxyl, molecular size distribution, structure and technological properties (empirical viscosity, hydration properties, thermal analysis and gel strength). The applied voltage of 14 kV resulted in the greatest depolymerization of the starch chains, while 20 kV allowed the formation of oxidized complexes, promoting crosslinking of the starches chain. The cold plasma technique did not affect the levels of resistant starches, but increased the starch digestibility. The increased carbonyl and carboxyl groups also influenced the paste viscosity, improved hydration properties. This study suggests that the cold plasma technique can be useful in the controlled modification of starches, producing starches with different technological properties.


Assuntos
Marantaceae/química , Gases em Plasma/química , Amido/química , Concentração de Íons de Hidrogênio
3.
Int J Biol Macromol ; 168: 187-194, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33248054

RESUMO

Ariá (Goeppertia allouia) is a tuber from the arrowroot's family widely found in the Brazilian Amazon. The tuber has a flavor similar to corn, besides high retrogradation when cooked, differing from other commercial starches. To enhance its added value, the Ariá starch was extracted to evaluate its potential as a food ingredient. The Ariá starch was compared to the commercially available corn and potato starches regarding their physicochemical, thermal, structural, and rheological properties based on the Duncan's test (p-value <0.05). The Ariá starch presented high amylose content (~38% w/w). Furthermore, the X-ray diffraction pattern confirmed its Type-C crystalline structure. The rheological properties showed that the starch gels presented high hardness and retrogradation as other studied starches. Ariá has great potential as a source of starch with low digestibility, increasing the satiety of food products.


Assuntos
Marantaceae/metabolismo , Tubérculos/química , Amido/química , Amilose/química , Brasil , Géis/química , Reologia , Solanum tuberosum/química , Solubilidade , Amido/isolamento & purificação , Difração de Raios X/métodos , Zea mays/química
4.
J Food Sci ; 85(11): 3722-3730, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32990365

RESUMO

The present study aims to produce arrowroot flour fermented by kefir grains, in addition to assessing the physicochemical, nutritional, and microbiological characteristics. Fermented arrowroot flour was produced at room temperature (approximately 25 to 28 °C). Fermentation was conducted in batch (6 kg of the substrate and 10% of kefir grains were added with homogenization every 3 hr). Samples were evaluated every 12 hr for both fermentation processes (fermentation process 1: 24 hr and fermentation process 2: 48 hr). The flours were evaluated for physicochemical, nutritional, and microbiological qualities, using a completely randomized design, considering only the variation in the duration of both fermentation processes (from 24 to 48 hr). The fermentation process positively modified the physicochemical, nutritional, and microbial characteristics of the flours. An increase in antioxidant activity (IC50 : control flour [CF] = 18.9 ± 0.13; arrowroot kefir flour [24 hr of fermentation; AKF1] = 15.36 ± 0.14; and arrowroot kefir flour [48 hr of fermentation; AKF2] = 13.84 ± 0.15), protein percentage (CF = 3.08 ± 0.12; AKF1 = 4.87 ± 0.33; and AKF2 = 6.00 ± 0.07), and organic acid (lactic, acetic, and propionic acids) production was observed, as well as modification in color (browning), the conformation of starch structures, and carbohydrate reduction. These results suggested that the "arrowroot kefir flours" open a new perspective for introduction in the market as a new product that can be used as food in nature or food ingredient for making bread, biscuits, pasta, and others, showing microbiological safety and functions properties. PRACTICAL APPLICATION: The fermented flours present improved nutritional characteristics due to the fermentation process, such as higher antioxidant activity and protein levels. Regarding the population growth and societal demand for healthier food, one possibility is to provide a fermented flour with added nutritional value and raise knowledge about the arrowroot. Thus, these flours can be used in various food items or as an ingredient in food preparations for consumers that desire a healthy diet.


Assuntos
Farinha/análise , Kefir/análise , Marantaceae/química , Pão/análise , Fermentação , Indústria Alimentícia , Valor Nutritivo , Amido/análise
5.
J Sci Food Agric ; 100(7): 3204-3211, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32105338

RESUMO

BACKGROUND: The incorporation of hydrocolloids into starch dispersions modifies their techno-functional properties, such as gelatinization, retrogradation, syneresis, and texture, among others. Their main function is to improve these properties and to promote greater stability of starch gels. Thus, the main objective of this study was to evaluate the effect of adding colloids (guar gum and xanthan gum) on the texture properties (hardness, elasticity, cohesiveness, and gumminess) and syneresis of the starch gels made from the common variety of arrowroot. Analysis of variance (ANOVA) and regression were carried out to analyze the effects of the treatments and variables with their respective interactions. RESULTS: The addition of guar gum and xanthan gum influenced the stability of the starch gels studied, and it was capable of reducing syneresis even at low concentrations, with a greater effect for xanthan gum. Both gums were capable of inhibiting syneresis at concentrations above 0.5%, throughout the storage time studied (5 days). The addition of these hydrocolloids was also shown to influence the following texture parameters: hardness, cohesiveness, and gumminess, but showed no effect on gel elasticity. CONCLUSION: The addition of hydrocolloids was shown to be an alternative way of increasing the stability and enhancing the textural properties of the starch gels in arrowroot. © 2020 Society of Chemical Industry.


Assuntos
Galactanos/química , Mananas/química , Marantaceae/química , Extratos Vegetais/química , Gomas Vegetais/química , Polissacarídeos Bacterianos/química , Amido/química , Coloides/química , Elasticidade , Géis/química , Dureza , Reologia
6.
J Microencapsul ; 37(1): 65-76, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31724471

RESUMO

The objective of this research work was to obtain blackberry pulp in microencapsulated powder with a of arrowroot starch/gum arabic mixture by spray drying. Experimental design, with 11 runs, was performed to evaluate the effects of inlet air temperature (100-150 °C) and encapsulating agent concentration (1:0.5-1:2, blackberry pulp solids: arrowroot starch/gum arabic) on the functional properties of powders. The ascorbic acid content and luminosity of the powder increased with increasing encapsulating agent concentrations, whereas the b* values decreased. Increasing the inlet air temperature and decreasing the encapsulating agent concentration, the content of anthocyanins also increased. The powders were able to reduce Fe+3 and to trap free radicals, showing antioxidant property. The temperature of 143 °C and concentration of encapsulating agent 1:1.78 were the ideal conditions to have high content of ascorbic acid and good content of anthocyanins and antioxidant properties.


Assuntos
Antocianinas/administração & dosagem , Antioxidantes/administração & dosagem , Goma Arábica/química , Marantaceae/química , Rubus/química , Amido/química , Antocianinas/química , Antioxidantes/química , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/química , Portadores de Fármacos/química , Composição de Medicamentos
7.
Hig. Aliment. (Online) ; 33(288/289): 1400-1404, abr.-maio 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482170

RESUMO

O objetivo de trabalho foi avaliar o efeito da adição de óleo de licuri nas propriedades do filme a base de amido de araruta (bioplástico). Foram elaborados dois filmes, um conteúdo óleo de licuri e outro sem o óleo na formulação. Os filmes foram caraterizados através de analises de espessura, solubilidade, atividade de água, permeabilidade a vapor de água, ensaios de tração e analise de cor. Os resultados apontaram que o óleo de licuri reduziu a resistência á tração, o modulo de Young, a atividade de água, a solubilidade e a luminosidade dos filmes de amido de araruta. Além disso, a adição do óleo levou à um aumento da espessura e permeabilidade ao vapor de água. A adição de óleo de licuri influenciou de forma favorável algumas propriedades do filme a base de amido de araruta.


Assuntos
Arecaceae , Biofilmes/efeitos dos fármacos , Marantaceae , Tensoativos/efeitos adversos , Óleos de Plantas/efeitos adversos , Amido , Permeabilidade , Solubilidade
8.
Hig. Aliment. (Online) ; 33(288/289): 1503-1507, abr.-maio 2019. ilus, tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482191

RESUMO

O amido é a principal fonte energética da alimentação humana e possui diversas funcionalidades tecnológicas. O objetivo deste trabalho foi avaliar as propriedades de pasta e a morfologia dos grânulos de amido de araruta. As propriedades viscoamilográficas do amido de araruta do Vale do Jiquiriçá e industrializado foram, respectivamente: viscosidade máxima de 7532 cP e 6865 cP, quebra da viscosidade de 4449 cP e 5378 cP, viscosidade final de 4897 cP e 2946 cP, retrogradação de 1814 cP e 1459 cP, tempo de pico 6,53 min e 5,73 min e temperatura de pasta igual a 71,05°C e 63,10°C. Os grânulos têm estrutura oval de tamanhos variados e danos na sua estrutura, possivelmente causados na extração. Essa caracterização serve como base para a determinação das condições ideais de processamento e usos em potencial para a indústria de alimentos.


Assuntos
Amido/fisiologia , Amido/ultraestrutura , Amidos e Féculas , Marantaceae , Microscopia Eletrônica de Varredura , Viscosidade
9.
Hig. aliment ; 33(288/289): 1400-1404, abr.-maio 2019. tab
Artigo em Português | VETINDEX | ID: vti-743455

RESUMO

O objetivo de trabalho foi avaliar o efeito da adição de óleo de licuri nas propriedades do filme a base de amido de araruta (bioplástico). Foram elaborados dois filmes, um conteúdo óleo de licuri e outro sem o óleo na formulação. Os filmes foram caraterizados através de analises de espessura, solubilidade, atividade de água, permeabilidade a vapor de água, ensaios de tração e analise de cor. Os resultados apontaram que o óleo de licuri reduziu a resistência á tração, o modulo de Young, a atividade de água, a solubilidade e a luminosidade dos filmes de amido de araruta. Além disso, a adição do óleo levou à um aumento da espessura e permeabilidade ao vapor de água. A adição de óleo de licuri influenciou de forma favorável algumas propriedades do filme a base de amido de araruta.(AU)


Assuntos
Marantaceae , Arecaceae , Óleos de Plantas/efeitos adversos , Biofilmes/efeitos dos fármacos , Tensoativos/efeitos adversos , Amido , Solubilidade , Permeabilidade
10.
Hig. aliment ; 33(288/289): 1503-1507, abr.-maio 2019. ilus, tab, graf
Artigo em Português | VETINDEX | ID: vti-23004

RESUMO

O amido é a principal fonte energética da alimentação humana e possui diversas funcionalidades tecnológicas. O objetivo deste trabalho foi avaliar as propriedades de pasta e a morfologia dos grânulos de amido de araruta. As propriedades viscoamilográficas do amido de araruta do Vale do Jiquiriçá e industrializado foram, respectivamente: viscosidade máxima de 7532 cP e 6865 cP, quebra da viscosidade de 4449 cP e 5378 cP, viscosidade final de 4897 cP e 2946 cP, retrogradação de 1814 cP e 1459 cP, tempo de pico 6,53 min e 5,73 min e temperatura de pasta igual a 71,05°C e 63,10°C. Os grânulos têm estrutura oval de tamanhos variados e danos na sua estrutura, possivelmente causados na extração. Essa caracterização serve como base para a determinação das condições ideais de processamento e usos em potencial para a indústria de alimentos.(AU)


Assuntos
Marantaceae , Amidos e Féculas , Microscopia Eletrônica de Varredura , Amido/ultraestrutura , Amido/fisiologia , Viscosidade
11.
Rev. Ciênc. Agrovet. (Online) ; 18(1): 65-72, 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1488299

RESUMO

Because it is an unconventional vegetable, arrowroot is appropriate for family farming; there is a need to find alternative ways to make its growing more sustainable, however. The objective of this study was to evaluate the productive performance of rhizomes and starch of arrowroot Seta intercropped with crotalaria. The experiment consisted of four treatments, corresponding to three harvest for crotalaria intercropped with arrowroot (90, 120 and 150 days after sowing) plus single cultivation of arrowroot. The experiment used a complete randomized block design with four replications. Mass production of crotalaria, macro and micronutrients contents in the cut material and infestation by invasive plants were evaluated at each harvest. At the harvest of arrowroot, productivity and format of rhizomes classes, macro and micronutrient contents were evaluated, and the export of nutrients and production of starch by rhizomes were estimated. The hasvests carried out at 120 and 150 DAS, despite propagating the highest values of weight and nutrients, provided lower yields of total, large rhizomes, and starch. Crotalaria hasvested at 90 DAS provided values higher than the cuts performed on 120 and 150 DAS for most evaluated variables, not differing from control, including starch. The intercropping provided less infestation by invasive plants. The intercropping between crotalaria and...


A araruta, por ser uma hortaliça não convencional é apropriada a exploração familiar, havendo necessidade de se encontrar formas alternativas para tornar seu o cultivo mais sustentável. Objetivou-se avaliar o desempenho produtivo de rizomas e de amido da araruta Seta cultivada em consórcio com a crotalária. O experimento constou de quatro tratamentos, correspondentes a três épocas de corte da crotalária associada com a araruta (90, 120 e 150 dias após a semeadura) mais o monocultivo da araruta. Utilizou-se o delineamento experimental de blocos casualizados, com quatro repetições. Nos cortes, avaliaram-se produção de massa de crotalária, conteúdo de macro e de micronutrientes no material cortado e a infestação por plantas invasoras. Na colheita da araruta, avaliaram-se produtividade e formato das classes de rizomas, teor de macro e micronutrientes, estimadas a exportação de nutrientes e a produção de amido pelos rizomas. Os cortes realizados aos 120 e 150 DAS, embora tenham veiculado maiores valores de massa e de nutrientes, proporcionou menores produtividades de rizomas grandes, total e de amido. O corte da crotalária aos 90 DAS proporcionou valores superiores aos cortes realizados aos 120 e 150 DAS para maioria das variáveis avaliadas, não diferindo do controle, inclusive para o amido. O consórcio proporcionou menor infestação por plantas invasoras. É agronomicamente viável...


Assuntos
Crotalaria/crescimento & desenvolvimento , Marantaceae/crescimento & desenvolvimento , Rizoma/crescimento & desenvolvimento
12.
R. Ci. agrovet. ; 18(1): 65-72, 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-28998

RESUMO

Because it is an unconventional vegetable, arrowroot is appropriate for family farming; there is a need to find alternative ways to make its growing more sustainable, however. The objective of this study was to evaluate the productive performance of rhizomes and starch of arrowroot Seta intercropped with crotalaria. The experiment consisted of four treatments, corresponding to three harvest for crotalaria intercropped with arrowroot (90, 120 and 150 days after sowing) plus single cultivation of arrowroot. The experiment used a complete randomized block design with four replications. Mass production of crotalaria, macro and micronutrients contents in the cut material and infestation by invasive plants were evaluated at each harvest. At the harvest of arrowroot, productivity and format of rhizomes classes, macro and micronutrient contents were evaluated, and the export of nutrients and production of starch by rhizomes were estimated. The hasvests carried out at 120 and 150 DAS, despite propagating the highest values of weight and nutrients, provided lower yields of total, large rhizomes, and starch. Crotalaria hasvested at 90 DAS provided values higher than the cuts performed on 120 and 150 DAS for most evaluated variables, not differing from control, including starch. The intercropping provided less infestation by invasive plants. The intercropping between crotalaria and...(AU)


A araruta, por ser uma hortaliça não convencional é apropriada a exploração familiar, havendo necessidade de se encontrar formas alternativas para tornar seu o cultivo mais sustentável. Objetivou-se avaliar o desempenho produtivo de rizomas e de amido da araruta Seta cultivada em consórcio com a crotalária. O experimento constou de quatro tratamentos, correspondentes a três épocas de corte da crotalária associada com a araruta (90, 120 e 150 dias após a semeadura) mais o monocultivo da araruta. Utilizou-se o delineamento experimental de blocos casualizados, com quatro repetições. Nos cortes, avaliaram-se produção de massa de crotalária, conteúdo de macro e de micronutrientes no material cortado e a infestação por plantas invasoras. Na colheita da araruta, avaliaram-se produtividade e formato das classes de rizomas, teor de macro e micronutrientes, estimadas a exportação de nutrientes e a produção de amido pelos rizomas. Os cortes realizados aos 120 e 150 DAS, embora tenham veiculado maiores valores de massa e de nutrientes, proporcionou menores produtividades de rizomas grandes, total e de amido. O corte da crotalária aos 90 DAS proporcionou valores superiores aos cortes realizados aos 120 e 150 DAS para maioria das variáveis avaliadas, não diferindo do controle, inclusive para o amido. O consórcio proporcionou menor infestação por plantas invasoras. É agronomicamente viável...(AU)


Assuntos
Marantaceae/crescimento & desenvolvimento , Crotalaria/crescimento & desenvolvimento , Rizoma/crescimento & desenvolvimento
13.
Ci. Rural ; 49(10): e20181037, 2019. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-23980

RESUMO

Arrowroot is a plant abundant in starch content, and because it does not possess gluten proteins in its composition, its utilization is of great interest in the production of food for people who are intolerant to these proteins. The substitution of gluten involves the use of thickening agents, such as pre-gelatinized starches or flours, which can be obtained by physical processes. In this context, the aim of this study was to evaluate the physicochemical and technological characteristics of arrowroot flour (AFU) modified by ultrasound, in the functioning of intensity and time, and modified by low humidity heat treatment (LHHT) as a function of temperature and time. Besides characterizing AFU and AFLHHT, we aimed their future application in products without gluten. All independent variables affected (P<0.05) water absorption index (WAI) and water solubility index (WSI) at 28 °C; WSI was at 80 °C, peak viscosity, final viscosity, setback and enthalpy of gelatinization (ΔH). The selected AFU was processed in 15 min at an ultrasound intensity of 43.5%, while AFLHHT was at 105 °C for 15 min. Neither of them presented significant differences in relation to their proximal composition. It is concluded that the modification of AF by both methods is feasible, and it is possible to predict its use in the formulation of foods without gluten, due to their physicochemical and technological characteristics which are more appropriate than those of AF.(AU)


A araruta é uma planta que apresenta conteúdo abundante de amido, e por não apresentar as proteínas do glúten em sua composição desperta o interesse da sua utilização na produção de alimentos para pessoas intolerantes a essas proteínas. A substituição do glúten envolve a utilização de agentes espessantes, como amidos ou farinhas pré-gelatinizados, que podem ser obtidos por meio de processos físicos. Neste contexto, o objetivo deste estudo foi avaliar as características físico-químicas e tecnológicas da farinha de araruta (FA), FA modificada por ultrassom (FAU) em função da intensidade e tempo, e FA modificada por tratamento térmico de baixa umidade (FATTBU) em função da temperatura e tempo, além de caracterizar FAU e FATTBU selecionadas, visando sua futura aplicação em produtos sem glúten. Todas as variáveis independentes afetaram (P<0.05): índice de absorção de água (IAA) e o índice de solubilidade em água (ISA) a 28 °C, ISA a 80 °C, viscosidade de pico, viscosidade final, tendência a retrogradação e entalpia de gelatinização (ΔH). A FAU selecionada foi processada em 15 min em intensidade do ultrassom de 43,5%, enquanto FATTBU a 105 ºC por 15 min. Ambas não apresentaram diferenças significativas em relação à composição proximal. A modificação da FA tanto por ultrassom como por tratamento térmico com baixa umidade é viável, e é possível prever a sua utilização na formulação de alimentos sem glúten, devido as suas características físico-químicas serem mais apropriadas que a da FA.(AU)


Assuntos
Marantaceae , Farinha , Ondas Ultrassônicas , Fenômenos Químicos/métodos , Glutens
14.
Food Sci Technol Int ; 22(3): 256-65, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26163566

RESUMO

The effect of heat-moisture treatment on structural, physicochemical, and rheological characteristics of arrowroot starch was investigated. Heat-moisture treatment was performed with starch samples conditioned to 28% moisture at 100 ℃ for 2, 4, 8, and 16 h. Structural and physicochemical characterization of native and modified starches, as well as rheological assays with gels of native and 4 h modified starches subjected to acid and sterilization stresses were performed. Arrowroot starch had 23.1% of amylose and a CA-type crystalline pattern that changed over the treatment time to A-type. Modified starches had higher pasting temperature and lower peak viscosity while breakdown viscosity practically disappeared, independently of the treatment time. Gelatinization temperature and crystallinity increased, while enthalpy, swelling power, and solubility decreased with the treatment. Gels from modified starches, independently of the stress conditions, were found to have more stable apparent viscosities and higher G' and G″ than gels from native starch. Heat-moisture treatment caused a reorganization of starch chains that increased molecular interactions. This increase resulted in higher paste stability and strengthened gels that showed higher resistance to shearing and heat, even after acid or sterilization conditions. A treatment time of 4 h was enough to deeply changing the physicochemical properties of starch.


Assuntos
Temperatura Alta , Marantaceae/química , Reologia , Amido/química , Configuração de Carboidratos , Análise de Alimentos , Água , Difração de Raios X
15.
Am J Bot ; 102(8): 1290-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26290552

RESUMO

UNLABELLED: • PREMISE OF THE STUDY: For tropical forest understory plants, the ability to grow, survive, and reproduce is limited by the availability of light. The extent to which reproduction incurs a survival or growth cost may change with light availability, plant size, and adaptation to shade, and may vary among similar species.• METHODS: We estimated size-specific rates of growth, survival, and reproduction (vital rates), for two neotropical understory herbs (order Zingiberales) in a premontane tropical rainforest in Costa Rica. During three annual censuses we monitored 1278 plants, measuring leaf area, number of inflorescences, and canopy openness. We fit regression models of all vital rates and evaluated them over a range of light levels. The best fitting models were selected using Akaike's Information Criterion.• KEY RESULTS: All vital rates were significantly influenced by size in both species, but not always by light. Increasing light resulted in higher growth and a higher probability of reproduction in both species, but lower survival in one species. Both species grew at small sizes but shrank at larger sizes. The size at which shrinkage began differed among species and light environments. Vital rates of large individuals were more sensitive to changes in light than small individuals.• CONCLUSIONS: Increasing light does not always positively influence vital rates; the extent to which light affects vital rates depends on plant size. Differences among species in their abilities to thrive under different light conditions and thus occupy distinct niches may contribute to the maintenance of species diversity.


Assuntos
Ecossistema , Heliconiaceae/fisiologia , Marantaceae/fisiologia , Costa Rica , Heliconiaceae/crescimento & desenvolvimento , Inflorescência/crescimento & desenvolvimento , Inflorescência/fisiologia , Marantaceae/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Floresta Úmida , Análise de Regressão , Reprodução , Clima Tropical
16.
Am J Bot ; 102(3): 350-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25784468

RESUMO

UNLABELLED: • PREMISE OF THE STUDY: Sexual reproduction is often associated with a cost in terms of reduced survival, growth, or future reproduction. It has been proposed that plant size and the environment (availability of key resources) can sometimes lower or even nullify the cost of reproduction.• METHODS: We address this issue experimentally with the Neotropical herb Goeppertia marantifolia, by manipulating sexual reproductive effort and measuring the demographic performance of plants and of their clonal offspring, in the context of natural variation in light availability.• KEY RESULTS: Plants in the high-reproductive-effort treatment grew less between seasons but did not differ in their probability of flowering the second season or in inflorescence size compared with plants in the low-effort treatment. Reproductive effort of parent plants influenced the leaf area of their clonal offspring. Plants that invested less in sexual reproduction produced clonal offspring that were initially larger than those produced by plants that invested more in reproduction. The magnitude of this effect was greater in parent plants that received two seasons of the manipulated reproductive effort than in those that received a single season. The trade-off between reproductive modes dampened with time, leading to smaller differences in clonal offspring leaf area between treatments over time.• CONCLUSIONS: We found evidence of a cost of reproduction and trade-offs between reproductive modes, although the magnitude of these costs was small. However, we found no evidence of lower costs of reproduction for larger plants or for plants in higher-light environments over our 2-yr study period.


Assuntos
Marantaceae/fisiologia , Luz Solar , Costa Rica , Marantaceae/crescimento & desenvolvimento , Marantaceae/efeitos da radiação , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Reprodução , Estações do Ano
17.
Biosci. j. (Online) ; 29(5): 1328-1338, sept./oct. 2013. ilus
Artigo em Português | LILACS | ID: biblio-946939

RESUMO

O presente estudo investigou a fenologia de floração, a biologia floral e os visitantes florais de Calathe acrocata. Os dados foram coletados no sub-bosque de um fragmento de Mata Atlântica no município de Igrapiúna, Bahia. Expedições mensais ocorreram de julho de 2009 a agosto de 2011. Mensalmente foram registrados dados da fenologia de floração de C. crocata. Foram obtidos dados de morfometria floral, de volume e concentração de néctar, além de registrado os atributos florais de C. crocata. As espécies de beija-flores visitantes florais foram registradas durante observações indivíduo-focal em plantas floridas, da aurora ao crepúsculo, determinando a frequência e o comportamento de forrageio. Testes de polinização natural e autopolinização foram realizados, além da eficiência na liberação do estilete. A floração desta espécie é anual e tem duração intermediária, possuindo correlação negativa com a temperatura. Calatheacrocata é uma espécie ornitófila; suas flores são tubulosas, com corola amarela, com comprimento médio de 24,3mm e abertura de 2,6mm. O néctar tem concentração média de 21% de açúcares, com volume médio produzido de 9,4µl. As flores foram visitadas legitimamente por quatro espécies de beija-flores, com frequência de 0,69 visitas por inflorescência/hora, sendo Phaethornis ruber eficiente no disparo do gatilho. O principal vetor de pólen de C. crocata foi Phaethornis ruber. Calathea crocata é uma espécie alógama e não se autopoliniza espontaneamente: somente houve produção de frutos no teste de polinização natural. Características mais pontuais, como a redução do gatilho, presentes nessa espécie, podem ser um indício da evolução da melitofilia para a ornitofilia, já observada na família Marantaceae, porém ainda pouco evidenciada no gênero.


The study goals were to investigate the flowering phenology, the floral biology, and the floral visitors of Calathea crocata. The data was collected in an understory fragment of Atlantic Forest at Igrapiúna city, state of Bahia. Field expeditions were conducted by month from July 2009 to August 2011. Every month flowering phenology data was documented. Besides floral morphometry, volume and concentration of nectar data, the floral attributes of C. crocata were collected. Hummingbird species that visited the plant was registered by focal observations in breeding plants from sunrise to sunrise, establishing the frequency and forage behavior. Natural pollination and self-pollination tests were conducted, in addition to trigger efficiency. The breeding season is annual, and has intermediate duration, being negatively correlated with the temperature. Calathea crocata is an ornithophilous species; its flowers are tubular, with yellow corollas of 24,3mm of length average, and 2,6mm of aperture average. The nectar has a sugar's concentration average of 21%, and a volume's average production of 9,4 µl. The flowers were visited legitimately by four hummingbird species. The visits frequency was 0,69 visits per inflorescence/hour, all of them were able to release the trigger. Phaethornis ruber was the mainly pollen vector of C. crocata. Calathea crocata is an allogamous species, and is not capable of spontaneous selfpollination: just the natural pollination test produced fruits. More specific features, as the trigger reduction, visible in this species, can be an evolutionary evidence from melitophily to ornithophily already seen in Marantaceae family, but not too noted on the genre.


Assuntos
Aves , Marantaceae , Flores , Floresta Úmida
18.
Biol Res ; 42(3): 315-26, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19915740

RESUMO

The ascorbate-glutathione (ASC-GSH) cycle has an important role in defensive processes against oxidative damage generated by drought stress. In this study, the changes that take place in apoplastic and symplastic ASC-GSH cycle enzymes of the leaf and petiole were investigated under drought stress causing leaf rolling in Ctenanthe setosa (Rose.) Eichler (Marantaceae). Apoplastic and symplastic extractions of leaf and petiole were performed at different visual leaf rolling scores from 1 to 4 (1 is unrolled, 4 is tightly rolled and the others are intermediate forms). Glutathione reductase (GR), a key enzyme in the GSH regeneration cycle, and ascorbate (ASC) were present in apoplastic spaces of the leaf and petiole, whereas dehydroascorbate reductase (DHAR), which uses glutathione as reductant, monodehydroascorbate reductase (MDHAR), which uses NAD(P)H as reductant, and glutathione were absent. GR, DHAR and MDHAR activities increased in the symplastic and apoplastic areas of the leaf. Apoplastic and symplastic ASC and dehydroascorbate (DHA), the oxidized form of ascorbate, rose at all scores except score 4 of symplastic ASC in the leaf. On the other hand, while reduced glutathione (GSH) content was enhanced, oxidized glutathione (GSSG) content decreased in the leaf during rolling. As for the petiole, GR activity increased in the apoplastic area but decreased in the symplastic area. DHAR and MDHAR activities increased throughout all scores, but decreased to the score 1 level at score 4. The ASC content of the apoplast increased during leaf rolling. Conversely, symplastic ASC content increased at score 2, however decreased at the later scores. While the apoplastic DHA content declined, symplastic DHA rose at score 2, but later was down to the level of score 1. While GSH content enhanced during leaf rolling, GSSG content did not change except at score 2. As well, there were good correlations between leaf rolling and ASC-GSH cycle enzyme activities in the leaf (GR and DHAR) and leaf rolling and GSSG. These results showed that in apoplastic and symplastic areas, ASC-GSH cycle enzymes leading ROS detoxification may have a role in controlling leaf rolling.


Assuntos
Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Marantaceae/enzimologia , Folhas de Planta/enzimologia , Rosa/enzimologia , Secas , Glutationa Redutase/metabolismo , NADH NADPH Oxirredutases/metabolismo , Oxirredutases/metabolismo , Estresse Fisiológico
19.
Biol. Res ; 42(3): 315-326, 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-531965

RESUMO

The ascorbate-glutathione (ASC-GSH) cycle has an important role in defensive processes against oxidative damage generated by drought stress. In this study, the changes that take place in apoplastic and symplastic ASC-GSH cycle enzymes of the leaf and petiole were investigated under drought stress causing leaf rolling in Ctenanthe setosa (Rose.) Eichler (Marantaceae). Apoplastic and symplastic extractions of leaf and petiole were performed at different visual leaf rolling scores from 1 to 4 (1 is unrolled, 4 is tightly rolled and the others are intermediate forms). Glutathione reductase (GR), a key enzyme in the GSH regeneration cycle, and ascorbate (ASC) were present in apoplastic spaces of the leaf and petiole, whereas dehydroascorbate reductase (DHAR), which uses glutathione as reductant, monodehydroascorbate reductase (MDHAR), which uses NAD(P)H as reductant, and glutathione were absent. GR, DHAR and MDHAR activities increased in the symplastic and apoplastic areas of the leaf. Apoplastic and symplastic ASC and dehydroascorbate (DHA), the oxidized form of ascorbate, rose at all scores except score 4 of symplastic ASC in the leaf. On the other hand, while reduced glutathione (GSH) content was enhanced, oxidized glutathione (GSSG) content decreased in the leaf during rolling. As for the petiole, GR activity increased in the apoplastic area but decreased in the symplastic area. DHAR and MDHAR activities increased throughout all scores, but decreased to the score 1 level at score 4. The ASC content of the apoplast increased during leaf rolling. Conversely, symplastic ASC content increased at score 2, however decreased at the later scores. While the apoplastic DHA content declined, symplastic DHA rose at score 2, but later was down to the level of score 1. While GSH content enhanced during leaf rolling, GSSG content did not change except at score 2. As well, there were good correlations between leaf rolling and ASC-GSH cycle enzyme activities ...


Assuntos
Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Marantaceae/enzimologia , Folhas de Planta/enzimologia , Rosa/enzimologia , Secas , Glutationa Redutase/metabolismo , NADH NADPH Oxirredutases/metabolismo , Oxirredutases/metabolismo , Estresse Fisiológico
20.
Proc Natl Acad Sci U S A ; 104(9): 3651-6, 2007 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-17360697

RESUMO

The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals and the associated transition to food production in various regions. One of these methodologies, starch grain analysis, recovers identifiable microfossils of economic plants directly off the stone tools used to process them. We report on new starch grain evidence from Panama demonstrating the early spread of three important New World cultigens: maize (Zea mays), manioc (Manihot esculenta), and arrowroot (Maranta arundinacea). Maize starch recovered from stone tools at a site located in the Pacific lowlands of central Panama confirms previous archaeobotanical evidence for the use of maize there by 7800-7000 cal BP. Starch evidence from preceramic sites in the less seasonal, humid premontane forests of Chiriquí province, western Panama, shows that maize and root crops were present by 7400-5600 cal BP, several millennia earlier than previously documented. Several local starchy resources, including Zamia and Dioscorea spp., were also used. The data from both regions suggest that crop dispersals took place via diffusion or exchange of plant germplasm rather than movement of human populations practicing agriculture.


Assuntos
Produtos Agrícolas/história , Demografia , Fósseis , Manihot , Marantaceae , Amido/análise , Zea mays , Arqueologia , Ecossistema , História Antiga , Humanos , Panamá , Dinâmica Populacional
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