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Patrick A. Jansen - One of the best experts on this subject based on the ideXlab platform.
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directed seed dispersal towards areas with low conspecific tree density by a scatter hoarding rodent
Ecology Letters, 2012Co-Authors: Ben T. Hirsch, Roland Kays, Patrick A. Jansen, Veronica E PereiraAbstract:Scatter-hoarding animals spread out cached seeds to reduce density-dependent theft of their food reserves. This behaviour could lead to directed dispersal into areas with lower densities of conspecific trees, where seed and seedling survival are higher, and could profoundly affect the spatial structure of plant communities. We tested this hypothesis with Central American agoutis and Astrocaryum standleyanum palm seeds on Barro Colorado Island, Panama. We radio-tracked seeds as they were cached and re-cached by agoutis, calculated the density of adult Astrocaryum trees surrounding each cache, and tested whether the observed number of trees around seed caches declined more than expected under random dispersal. Seedling establishment success was negatively dependent on seed density, and agoutis carried seeds towards locations with lower conspecific tree densities, thus facilitating the escape of seeds from natural enemies. This behaviour may be a widespread mechanism leading to highly effective seed dispersal by scatter-hoarding animals.
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Directed seed dispersal towards areas with low conspecific tree density by a scatter‐hoarding rodent
Ecology letters, 2012Co-Authors: Ben T. Hirsch, Roland Kays, Veronica E Pereira, Patrick A. JansenAbstract:Scatter-hoarding animals spread out cached seeds to reduce density-dependent theft of their food reserves. This behaviour could lead to directed dispersal into areas with lower densities of conspecific trees, where seed and seedling survival are higher, and could profoundly affect the spatial structure of plant communities. We tested this hypothesis with Central American agoutis and Astrocaryum standleyanum palm seeds on Barro Colorado Island, Panama. We radio-tracked seeds as they were cached and re-cached by agoutis, calculated the density of adult Astrocaryum trees surrounding each cache, and tested whether the observed number of trees around seed caches declined more than expected under random dispersal. Seedling establishment success was negatively dependent on seed density, and agoutis carried seeds towards locations with lower conspecific tree densities, thus facilitating the escape of seeds from natural enemies. This behaviour may be a widespread mechanism leading to highly effective seed dispersal by scatter-hoarding animals.
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Effects of Food Availability on Space and Refuge Use by a Neotropical Scatterhoarding Rodent
Biotropica, 2012Co-Authors: Willem-jan Emsens, Lennart Suselbeek, Ben T. Hirsch, Roland Kays, Annemarie J. S. Winkelhagen, Patrick A. JansenAbstract:Animals that rely on refuges for safety can theoretically increase their foraging area without simultaneously increasing predation risk and travel costs by using more refuges. The key prediction of this theory, a negative correlation between food abundance, home range size and the number of refuges used, has never been empirically tested. We determined how home range size and refuge use by the Central American agouti (Dasyprocta punctata) varied across a gradient of abundance of the agoutis' principal food source: seeds and fruits of the palm Astrocaryum standleyanum. We used both manual and automated radio telemetry to measure space use of 11 agoutis during 2 mo of the Astrocaryum fruiting season, and of another set of 10 agoutis during 6 mo in which the animals largely relied on cached Astrocaryum seeds. We found that agoutis living in areas of lower food density had larger home ranges, and that all individuals used multiple refuges. The number of refuges, however, was not correlated with home range size. Consequently, agoutis that had larger home ranges roamed farther from their refuges. These results suggest that agoutis increase their home range size in response to food scarcity at the cost of their safety.
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large scale spatial variation in palm fruit abundance across a tropical moist forest estimated from high resolution aerial photographs
Ecography, 2008Co-Authors: Patrick A. Jansen, Stephanie A Bohlman, Carol X Garzonlopez, Han Olff, Helene C Mullerlandau, Joseph S WrightAbstract:Fruit abundance is a critical factor in ecological studies of tropical forest animals and plants, but difficult to measure at large spatial scales. We tried to estimate spatial variation in fruit abundance on a relatively large spatial scale using low altitude, high-resolution aerial photography. We measured fruit production for all 555 individuals of the arborescent palm Astrocaryum standleyanum across 25 ha of mapped tropical moist forest on Barro Colorado Island, Panama, by visually counting fruits from the ground. Simultaneously, we used high-resolution aerial photographs to map sun-exposed crowns of the palm across the same area, which were then linked to ground-mapped stems. First, we verified that the fruit crop size of individual trees was positively associated with both crown presence on aerial photos and crown area visible on aerial photos. Then, we determined how well spatial variation in Astrocaryum fruit density across the study area was predicted by spatial densities of photo-detected crowns and crown area compared to spatial densities of ground-mapped stems and stem diameters. We found a positive association of fruit crop size with crown visibility on aerial photographs. Although representing just one third of all individuals in the study area, photo-detected crowns represented 57% of all fruits produced. The spatial pattern of photo-detected crowns was strongly correlated with the spatial pattern of fruit abundance based on direct fruit counts, and correctly showed the areas with the highest and lowest fruit abundances. The spatial density of photo-detected crowns predicted spatial variation in fruit abundance equally well as did the spatial density of ground-mapped stems. Photo-detected crown area did not yield a better prediction. Our study indicates that remote sensing of crowns can be a reliable and cost-effective method for estimating spatial variation in fruit abundance across large areas for highly distinctive canopy species. Our study is also among the few to provide empirical evidence for a positive relationship between crown exposure of forest trees and fruit production.
Matheus D. Baldissera - One of the best experts on this subject based on the ideXlab platform.
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Treatment with tucumã oil (Astrocaryum vulgare) for diabetic mice prevents changes in seric enzymes of the purinergic system: Improvement of immune system.
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie, 2017Co-Authors: Matheus D. Baldissera, Michele Rorato Sagrillo, Carine F. Souza, Thirssa H. Grando, Aleksandro S. Da Silva, Pedro H. Doleski, Daniela B.r. Leal, Silvia Gonzalez MonteiroAbstract:Abstract The aim of this study was to evaluate the enzymatic activity of the purinergic system in sera samples from alloxan-induced diabetic mice treated with tucuma oil (Astrocaryum vulgare). For this, the mice were divided into four groups (n = 6): control/water (the group CW); control/tucuma oil (the group CT); diabetic/water (the group DW), and diabetic/tucuma oil (the group DT) treated for 14 days with 5.0 mL kg−1 via oral gavage. On day 14 post-treatment, mice were submitted to euthanasia and blood samples were collected by cardiac puncture. Tucuma oil treatment significantly decreased (p
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The use of tucumã oil (Astrocaryum vulgare) in alloxan-induced diabetic mice: effects on behavior, oxidant/antioxidant status, and enzymes involved in brain neurotransmission.
Molecular and cellular biochemistry, 2017Co-Authors: Matheus D. Baldissera, Carine F. Souza, Thirssa H. Grando, Aleksandro S. Da Silva, Lenita M. Stefani, Michele R Sagrillo, Silvia G MonteiroAbstract:The aim of this study was to investigate the effects of tucumã oil (Astrocaryum vulgare) on memory, enzymatic activities of sodium-potassium pump (Na+, K+-ATPase) and acetylcholinesterase (AChE) in the brain of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): the group A (non-diabetic/water), the group B (non-diabetic/tucumã oil), the group C (diabetic/water), and the group D (diabetic/tucumã oil) treated 14 days with 5.0 mL kg-1 via oral gavage. Untreated diabetic mice (the group C) showed memory deficit, increased levels of thiobarbituric acid reactive species (TBARS) and protein carbonylation (PC), and decreased (p
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Antihyperglycemic, antioxidant activities of tucumã oil (Astrocaryum vulgare) in alloxan-induced diabetic mice, and identification of fatty acid profile by gas chromatograph: New natural source to treat hyperglycemia
Chemico-biological interactions, 2017Co-Authors: Matheus D. Baldissera, Kátia Nascimento, Michele Rorato Sagrillo, Ivana Beatrice Mânica Da Cruz, Carine F. Souza, Thirssa H. Grando, Luciana F. Cossetin, Aleksandro S. Da Silva, Alencar Machado, Lenita M. StefaniAbstract:Abstract The aim of the study was to investigate the effect of the oral administration of tucuma oil (Astrocaryum vulgare) on glucose and insulin levels, oxidative status, and pancreatic genotoxic parameters of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): control/water; control/tucuma oil; diabetic/water; diabetic/tucuma oil treated for 14 days with 5.0 mL kg−1 via oral gavage. Gas chromatograph characterization demonstrated that oleic/elaidic fatty acid is the most abundant component present in this oil, followed by palmitic and stearic fatty acids. Our results demonstrated an increase (p
Betty Millan - One of the best experts on this subject based on the ideXlab platform.
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variabilidad vegetativa intra e interespecifica de Astrocaryum chonta y a javarense arecaceae en jenaro herrera loreto peru
Revista Peruana de Biología, 2014Co-Authors: Miguel Machahua, Francis Kahn, Betty MillanAbstract:Vegetative quantitative characters from adult, juvenile II, juvenile I and seedlings of Astrocaryum chonta and Astrocaryum javarense for four populations of Jenaro Herrera were analyzed in order to observe the patterns of vegetative variation at intra and interspecific level. The biometric data were analyzed using ANOVA (p<0.05 and 0.01). At intraspecific level the 37% and 64% of vegetative characters are significantly different in Astrocaryum chonta and Astrocaryum javarense, while at interspecific level the 81% are significantly different.
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Variabilidad vegetativa intra e interespecífica de Astrocaryum chonta y A. javarense (Arecaceae) en Jenaro Herrera, Loreto, Perú
Revista Peruana de Biología, 2014Co-Authors: Miguel Machahua, Francis Kahn, Betty MillanAbstract:Vegetative quantitative characters from adult, juvenile II, juvenile I and seedlings of Astrocaryum chonta and Astrocaryum javarense for four populations of Jenaro Herrera were analyzed in order to observe the patterns of vegetative variation at intra and interspecific level. The biometric data were analyzed using ANOVA (p
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anatomia del fruto y perianto en especies peruanas del genero Astrocaryum arecaceae descripcion e importancia taxonomica
Revista Peruana de Biología, 2014Co-Authors: Cecilia Vegas, Jean-christophe Pintaud, Betty Millan, Francis KahnAbstract:The anatomy of fruit and perianth is described for 12 Peruvian species of the genus Astrocaryum. The fruit displays three well-defined layers: exocarp with fiber boundles and sclereids, free or grouped; mesocarp with parenchyma and schizogenous cavities; and heavily sclerified endocarp. Density of vascular bundles of the calyx is higher in the two species of subgenus Astrocaryum and lower in the ten species of subgenus Monogynanthus. Several structures exhibit useful characters for distinguishing subsections and species in the Huicungo section. Such characters include the form and location of fiber packages of the calyx, density of brachysclereids in the distal zone of the exocarp, form of vascular bundles of the corolla, raphides in the mesocarp, presence or absence of trichomes, structure of trichomes, presence or absence of laminar colenchyma in the exocarp, staminodial ring free or adnate and continuity with the corolla. An identification key based on these anatomical characters is supplied.
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Cenozoic colonization and diversification patterns of tropical American palms: evidence from Astrocaryum (Arecaceae)
Botanical Journal of the Linnean Society, 2012Co-Authors: Julissa Roncal, Francis Kahn, Betty Millan, Thomas L. P. Couvreur, Jean-christophe PintaudAbstract:With 788 species in 67 genera in the Neotropics, Arecaceae are an important ecological and economic component of the region. We review the influence of geological events such as the Pebas system, the Andean uplift and the land connections between South and Central/North America, on the historical assembly of Neotropical palms. We present a case study of the palm genus Astrocaryum (40 species) as a model for evaluating colonization and diversification patterns of lowland Neotropical taxa. We conducted a Bayesian dated phylogenetic analysis based on four low-copy nuclear DNA regions and a biogeographical analysis using the dispersal, extinction and cladogenesis model. Cladogenesis of Western Amazonian Astrocaryum spp. (c. 6 Mya) post-dated the drainage of the aquatic Pebas system, supporting the constraining role of Pebas on in situ diversification and colonization. The ancestral distribution of Astrocaryum spp. in the Guiana Shield supported the hypothesis of an old formation that acted as a source area from which species colonized adjacent regions, but an earliest branching position for Guianan species was not confidently recovered. A twofold increase in diversification rate was found in a clade, the ancestor of which occupied the Guiana Shield (c. 13 Mya, a time of climatic change and Andean uplift). © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ●●, ●●–●●.
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Anatomía y propiedades físico-químicas de la fibra de chambira
Revista Peruana de Biología, 2012Co-Authors: Manuel Marín, Betty Millan, Francis KahnAbstract:The anatomy of the unopened spear leaf of the chambira palm (Astrocaryum chambira), from which chambira fiber is extracted, is described and compared with that of three species (Astrocaryum jauari, occasionally used for fiber extraction, A. standleyanum and A. perangustatum, which do not provide any fiber). Chambira fiber consists of non-vascular fiber strands closely adhered to the adaxial hypodermis; this forms a compact unit, which makes it easy to separate from the rest of the lamina. A similar arrangement is found in Astrocaryum jauari; however, the non-vascular fiber cells are shorter and fewer per strand. Differences in leaf anatomy of Astrocaryum standleyanum and A. perangustatum may explain why fiber is not extracted: Astrocaryum standleyanum has a dense row of non-vascular fibrous strands under the adaxial hypodermis similar to Astrocaryum chambira but the large size of non-vascular fibrous strands that are located in the abaxial part of the mesophyll makes it difficult to properly extract fiber as is done with chambira. In Astrocaryum perangustatum, non-vascular fiber strands are small and irregularly dispersed in the mesophyll, which makes it impossible to extract quality fibers. Density, thickness and tensile strength are higher in chambira fiber than in jauari fiber. Chambira fiber presents a very high cellulose content (93.9%), while lignin content is low (4.2%). The ultrastructure of the cell wall of the non-vascular fiber is described for Astrocaryum chambira only. The major trait is a three-layered cell wall, with a notably thick inner layer. The physicochemical properties of chambira fiber are compared with other vegetal fibers used by the industry.
Michele Rorato Sagrillo - One of the best experts on this subject based on the ideXlab platform.
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Phytochemical analysis and evaluation of the antioxidant and antiproliferative effects of Tucumã oil nanocapsules in breast adenocarcinoma cells (MCF-7)
Natural Product Research, 2019Co-Authors: Kátia Nascimento, Priscila Marquezan Copetti, Andrêssa Silva Fernandes, Bruna Klein, Aline De Oliveira Fogaça, Leila Queiroz Zepka, Roger Wagner, Aline Ferreira Ourique, Michele Rorato Sagrillo, José Edson Paz Da SilvaAbstract:In this work was to develop an inedited nanocapsule with tucuma oil (Astrocaryum vulgare). The oil presents of phytosterols (squalene and β-sitosterol), all-trans-beta-carotene, acids oleic and pal...
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The Tucumã of Amazonas—Astrocaryum aculeatum
Exotic Fruits, 2018Co-Authors: Roberto Christ Vianna Santos, Michele Rorato Sagrillo, Euler Esteves Ribeiro, Ivana Beatrice Mânica Da CruzAbstract:Abstract Astrocaryum aculeatum, popularly known as tucuma, belongs to Arecaceae family and is also called tucuma-do-amazonas, tucumanzeiro, tucuma-grande, or tucuma-accu. This palm tree is native to the Amazon, occurring in northern Bolivia, Colombia, Venezuela, Guyana, Suriname, and Brazil being found mainly in the state of Amazonas. It is a large palm tree, with an upright stipe of 10–30 m, being covered in its upper half by black or brown thorns arranged in rings. The leaves have a feather shape and have thorns on its entire length, measuring 4–5 m long. The productivity of the palm tree is around 12–50 kg/year, which starts slowly and late, when the tree reaches 7 years at least with height between 6 and 9 m. The fruit weighs 20–100 grams and is yellowish-green, with a length of 4.5–6.0 and 3.5 cm–4.5 cm in diameter. The pulp has a coloration ranging from yellow to orange and has 9% protein, 55% oil, and represents 22% of the fruit weight. A number of substances have been identified: carotenoids (62.6 mg/g of fresh pulp), being 21 isoforms, with a predominance of 75% of all-trans beta-carotene; flavonoids like catechin and quercetin and ascorbic acid (58 mg/100 g). It is currently consumed by the Amazon population, with the use of nearly all the plants. The stipe is applied to the construction of houses and furniture. The meristem is used in food. The flesh of the fruit, which is the edible part, is widely used for the production of tucuma wine, ice cream, popsicles, soap, as well as animal feed. The core is used for the production of handicrafts, such as rings, bracelets, and necklaces. Furthermore, the core has been widely used to extract an oil to be used in the cosmetic and food industry, and in the production of biodiesel. The leaves have been used in the production of baskets, hats and Tucum (a high-quality fiber for the production of hammocks and bags) is extracted from them. Recent studies, suggest that the hydroalcoholic extract of tucuma has an antioxidant capacity quite high and also has some action in modulating the production of free radicals in healthy blood exposed to hydrogen peroxide. These results indicate that tucuma may have chemotherapeutic potential.
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the tucuma of amazonas Astrocaryum aculeatum
2018Co-Authors: Roberto Christ Vianna Santos, Michele Rorato Sagrillo, Euler Esteves Ribeiro, Ivana Beatrice Mânica Da CruzAbstract:Abstract Astrocaryum aculeatum, popularly known as tucuma, belongs to Arecaceae family and is also called tucuma-do-amazonas, tucumanzeiro, tucuma-grande, or tucuma-accu. This palm tree is native to the Amazon, occurring in northern Bolivia, Colombia, Venezuela, Guyana, Suriname, and Brazil being found mainly in the state of Amazonas. It is a large palm tree, with an upright stipe of 10–30 m, being covered in its upper half by black or brown thorns arranged in rings. The leaves have a feather shape and have thorns on its entire length, measuring 4–5 m long. The productivity of the palm tree is around 12–50 kg/year, which starts slowly and late, when the tree reaches 7 years at least with height between 6 and 9 m. The fruit weighs 20–100 grams and is yellowish-green, with a length of 4.5–6.0 and 3.5 cm–4.5 cm in diameter. The pulp has a coloration ranging from yellow to orange and has 9% protein, 55% oil, and represents 22% of the fruit weight. A number of substances have been identified: carotenoids (62.6 mg/g of fresh pulp), being 21 isoforms, with a predominance of 75% of all-trans beta-carotene; flavonoids like catechin and quercetin and ascorbic acid (58 mg/100 g). It is currently consumed by the Amazon population, with the use of nearly all the plants. The stipe is applied to the construction of houses and furniture. The meristem is used in food. The flesh of the fruit, which is the edible part, is widely used for the production of tucuma wine, ice cream, popsicles, soap, as well as animal feed. The core is used for the production of handicrafts, such as rings, bracelets, and necklaces. Furthermore, the core has been widely used to extract an oil to be used in the cosmetic and food industry, and in the production of biodiesel. The leaves have been used in the production of baskets, hats and Tucum (a high-quality fiber for the production of hammocks and bags) is extracted from them. Recent studies, suggest that the hydroalcoholic extract of tucuma has an antioxidant capacity quite high and also has some action in modulating the production of free radicals in healthy blood exposed to hydrogen peroxide. These results indicate that tucuma may have chemotherapeutic potential.
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Treatment with tucumã oil (Astrocaryum vulgare) for diabetic mice prevents changes in seric enzymes of the purinergic system: Improvement of immune system.
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie, 2017Co-Authors: Matheus D. Baldissera, Michele Rorato Sagrillo, Carine F. Souza, Thirssa H. Grando, Aleksandro S. Da Silva, Pedro H. Doleski, Daniela B.r. Leal, Silvia Gonzalez MonteiroAbstract:Abstract The aim of this study was to evaluate the enzymatic activity of the purinergic system in sera samples from alloxan-induced diabetic mice treated with tucuma oil (Astrocaryum vulgare). For this, the mice were divided into four groups (n = 6): control/water (the group CW); control/tucuma oil (the group CT); diabetic/water (the group DW), and diabetic/tucuma oil (the group DT) treated for 14 days with 5.0 mL kg−1 via oral gavage. On day 14 post-treatment, mice were submitted to euthanasia and blood samples were collected by cardiac puncture. Tucuma oil treatment significantly decreased (p
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Antihyperglycemic, antioxidant activities of tucumã oil (Astrocaryum vulgare) in alloxan-induced diabetic mice, and identification of fatty acid profile by gas chromatograph: New natural source to treat hyperglycemia
Chemico-biological interactions, 2017Co-Authors: Matheus D. Baldissera, Kátia Nascimento, Michele Rorato Sagrillo, Ivana Beatrice Mânica Da Cruz, Carine F. Souza, Thirssa H. Grando, Luciana F. Cossetin, Aleksandro S. Da Silva, Alencar Machado, Lenita M. StefaniAbstract:Abstract The aim of the study was to investigate the effect of the oral administration of tucuma oil (Astrocaryum vulgare) on glucose and insulin levels, oxidative status, and pancreatic genotoxic parameters of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): control/water; control/tucuma oil; diabetic/water; diabetic/tucuma oil treated for 14 days with 5.0 mL kg−1 via oral gavage. Gas chromatograph characterization demonstrated that oleic/elaidic fatty acid is the most abundant component present in this oil, followed by palmitic and stearic fatty acids. Our results demonstrated an increase (p
Lenita M. Stefani - One of the best experts on this subject based on the ideXlab platform.
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The use of tucumã oil (Astrocaryum vulgare) in alloxan-induced diabetic mice: effects on behavior, oxidant/antioxidant status, and enzymes involved in brain neurotransmission.
Molecular and cellular biochemistry, 2017Co-Authors: Matheus D. Baldissera, Carine F. Souza, Thirssa H. Grando, Aleksandro S. Da Silva, Lenita M. Stefani, Michele R Sagrillo, Silvia G MonteiroAbstract:The aim of this study was to investigate the effects of tucumã oil (Astrocaryum vulgare) on memory, enzymatic activities of sodium-potassium pump (Na+, K+-ATPase) and acetylcholinesterase (AChE) in the brain of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): the group A (non-diabetic/water), the group B (non-diabetic/tucumã oil), the group C (diabetic/water), and the group D (diabetic/tucumã oil) treated 14 days with 5.0 mL kg-1 via oral gavage. Untreated diabetic mice (the group C) showed memory deficit, increased levels of thiobarbituric acid reactive species (TBARS) and protein carbonylation (PC), and decreased (p
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Antihyperglycemic, antioxidant activities of tucumã oil (Astrocaryum vulgare) in alloxan-induced diabetic mice, and identification of fatty acid profile by gas chromatograph: New natural source to treat hyperglycemia
Chemico-biological interactions, 2017Co-Authors: Matheus D. Baldissera, Kátia Nascimento, Michele Rorato Sagrillo, Ivana Beatrice Mânica Da Cruz, Carine F. Souza, Thirssa H. Grando, Luciana F. Cossetin, Aleksandro S. Da Silva, Alencar Machado, Lenita M. StefaniAbstract:Abstract The aim of the study was to investigate the effect of the oral administration of tucuma oil (Astrocaryum vulgare) on glucose and insulin levels, oxidative status, and pancreatic genotoxic parameters of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): control/water; control/tucuma oil; diabetic/water; diabetic/tucuma oil treated for 14 days with 5.0 mL kg−1 via oral gavage. Gas chromatograph characterization demonstrated that oleic/elaidic fatty acid is the most abundant component present in this oil, followed by palmitic and stearic fatty acids. Our results demonstrated an increase (p
