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This work was carried out to investigate the pulp composition of four mango cultivars (Haden, Tommy Atkins and Ubá) at the ripening stage in relation to three components with antioxidant potential (total phenolics, carotenoids and ascorbic acid). Total phenolic compound content was estimated by the Folin-Ciocalteu reagent and total carotenoid content by spectrophotometry at 450 nm. The contents of β-carotene and total vitamin C (ascorbic acid and dehydroascorbic acid) were quantified by high performance liquid chromatography. Differences were found among the four mango cultivars in all the components analyzed. The content of phenolic compounds ranged from 48.40 (Haden) to 208.70 mg/100 g (Ubá); total carotenoid from 1.91 (Haden) to 2.63 mg/100 g (Palmer); β-carotene from 661.27 (Palmer) to 2,220 μg/100 g (Ubá) and total ascorbic acid ranged from 9.79 (Tommy Atkins) to 77.71 mg/100 g (Ubá). These results corroborated previous information that mangoes are a good source of antioxidants in human diet.  相似文献   
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Forty genotypes representing maize genetic diversity from the Island of Madeira were screened for resistance to aluminum (Al) in nutrient solution. Seeds of maize were obtained from local farmers from field plots spread around the island in a range of altitudes from 99 to 1000 m above sea level. The content of ionic aluminum and the pH of soils cultivated with maize were determined. The mean pH value of all examined soils was 4.9, while the mean ionic Al content was 0.76 cmol kg–1. Seventy‐two hours (h) exposure to 100 and 200 μM Al followed by a 48 h recovery period of 4‐day old seedlings revealed significant differences in Al resistance in the Madeiran maize germplasm. Root survival and regrowth exceeding 80 % of the seedlings were observed in 22 and 8 of the tested genotypes screened at 100 and 200 μM Al in nutrient solution. High Al resistance among Madeiran maize genotypes appeared not to be associated with the lower pH of soil, and did not correlate with the amount of soil Al3+ or the altitude at the site of collection. The high level of Al resistance of the maize cultivars indicates an initial genetic trait enhanced by open pollination of maize.  相似文献   
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Land degradation reducing vegetation cover may affect the soil surface‐active fauna because both aboveground and belowground invertebrates depend on complex plant communities. In this study, we evaluated the effect of land degradation and restoration on soil fauna in northeast Brazil. Sites differed in degradation status: native vegetation, moderately degraded land, highly degraded land, and land under restoration for 4 years. Araneae and Coleoptera densities were significantly higher in natural vegetation and restored land (8 ± 4 ind./trap and 41 ± 21 ind./trap, respectively) than in degraded lands (−73% and −81%, respectively). The density of Formicidae was significantly higher in natural vegetation (206 ± 181 ind./trap) than in highly degraded land (32 ± 24 ind./trap), while restored land (51 ± 10 ind./trap) and moderately degraded land (37 ± 14 ind./trap) did not differ significantly from the other degradation levels. The density of Orthoptera did not follow the aforementioned patterns, while invertebrate groups mostly had highest densities in natural land and restored land. Linear regressions showed a strong negative relation between faunal density and soil bulk density, and a positive relation with soil organic matter due to an increase in plant cover. Our results indicate that land degradation simplifies soil surface‐active invertebrate communities with pronounced decreases in the density of Araneae, Coleoptera, and Formicidae, but that land restoration practices may recover the density of soil fauna even after only 4 years. Araneae, Coleoptera, and Formicidae respond sensitively to land degradation and restoration practice and are suggested as indicator groups for restoration success. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Genetic Resources and Crop Evolution - Croton grewioides Baill. is a medicinal and aromatic species with proven biological activity. Considering the economic potential of the species, the use of...  相似文献   
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The ecology of cyathostomin larvae was evaluated in different seasons, from July 2007 to June 2008, in the municipality of Seropédica, Rio de Janeiro state, southeastern Brazil. Samples of feces and grass were collected every 15 days at 8 AM and 5 PM and the infective larvae were recovered by the Baermann technique. Leaves of the grass Brachiaria humidicola were cut to 20 cm, which is the length containing most of the larvae. The highest number of larvae was recorded at 8 AM the winter (8300 L(3)kg(-1)dm) and spring (5300 L(3)kg(-1)dm). These results demonstrate that climate conditions can affect the recovery of larvae and that rain and temperature contributed to the migration and survival of the larvae, which were available throughout the year in the study area.  相似文献   
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The digenetic trematode Eurytrema coelomaticum is a parasite of pancreatic ducts of ruminants. The ultrastructure of the mother and daughter sporocysts of E. coelomaticum was analyzed. The mother sporocyst was attached to the coelome of the intestine wall of intermediate snail host Bradybaena similaris, intimately adhered in some regions. It presents a highly folded tegument with granules and the body wall was composed by an outer syncitial layer, basal lamina, and circular and longitudinal muscle layer. Below was the cell body (cyton) with the nucleus. The daughter sporocysts obtained by dissection exhibited many granules and secretory vesicle in the outer layer indicating an intense secretory activity. The body wall presented the same layers of the mother sporocysts, but the outer syncitial layer invaginated and an amorphous layer was present between the syncitial and circular muscle layers. The protonephridial excretory system was viewed. The anterior and posterior end of the expelled sporocyst exhibit a degenerated structure, but biological activity still occurred in these regions. The swollen middle of the body was filled by a lamellar structure formed by degenerating membranes, but the excretory system was preserved. The endocyst wall was fibrilar and filled by cercariae and amorphous, membranous and secretory material inside it. These results were discussed.  相似文献   
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