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101.
Carotenoids from Marine Microalgae: A Valuable Natural Source for the Prevention of Chronic Diseases
Maria Filomena de Jesus Raposo Alcina Maria Miranda Bernardo de Morais Rui Manuel Santos Costa de Morais 《Marine drugs》2015,13(8):5128-5155
Epidemiological studies have shown a relation between antioxidants and the prevention of several chronic diseases. Microalgae are a potential novel source of bioactive molecules, including a wide range of different carotenoids that can be used as nutraceuticals, food supplements and novel food products. The objective of this review is (i) to update the research that has been carried out on the most known carotenoids produced by marine microalgae, including reporting on their high potentialities to produce other less known important compounds; (ii) to compile the work that has been done in order to establish some relationship between carotenoids and oxidative protection and treatment; (iii) to summarize the association of oxidative stress and the various reactive species including free radicals with several human diseases; and (iv) to provide evidence of the potential of carotenoids from marine microalgae to be used as therapeutics to treat or prevent these oxidative stress-related diseases. 相似文献
102.
R.B. Silva K.P. Lanas E.E.V. Miranda F.A.M. Silva F.H.R. Baio 《Soil & Tillage Research》2009,103(2):265-270
The indiscriminate management and use of soils without moisture control has changed the structure of it due to the increment of the traffic by agricultural machines through the years, causing in consequence, a soil compaction and yield reduction in the areas of intensive traffic. The purpose of this work was to estimate and to evaluate the performance of preconsolidation pressure of the soil and shear stress as indicators of changes on soil structure in fields cropped with sugarcane, as well as the impact of management processes in an Eutrorthox soil structure located in Sao Paulo State. The experimental field was located in Piracicaba's rural area (Sao Paulo State, Brazil) and has been cropped with sugarcane, in the second harvest cycle. The soil was classified by EMBRAPA [EMBRAPA, 1999. Centro Nacional de Pesquisa de Solos. Sistema Brasileiro de Classificação de Solos, Embrapa, Brasília, 412 pp.] as an Eutrorthox. Undisturbed samples were collected and georeferenced in a grid of 60 m × 60 m from two depths: 0–0.10 m (superficial layer – SL) and in the layer of greatest mechanical resistance (LGMR), previously identified by cone index (CI). The investigated variables were pressure preconsolidation (σp), apparent cohesion (c) and internal friction angle (). The conclusions from the results were that the SLSC was predicted satisfactorily from σp as a function of soil moisture; thus, decisions about machinery size and loading (contact pressures) can be taken. Apparent cohesion (c), internal friction angle () and the Coulomb equation were significantly altered by traffic intensity. The σp, c and maps were shown to be important tools to localize and visualize soil compaction and mechanical resistance zones. They constitute a valuable resource to evaluate the traffic impact in areas cropped with sugarcane in State of Sao Paulo, Brazil. 相似文献
103.
J. D. C. Figueroa Z. J. E. Hernndez M. J. J. Vles P. Rayas‐Duarte H. E. Martínez‐Flores N. Ponce‐García 《Cereal Chemistry》2011,88(1):12-18
Three samples were selected representing bread, soft, and durum wheat. Uniaxial compression and stress relaxation tests were performed on wheat kernels. Force‐deformation curves from intact wheat grain typically exhibited at least two points of inflection (PI) at ≈0.1 and 0.2 mm displacement. The first PI is related to the mechanical properties of all the bran layers. The second PI (0.2 mm) seems to be the endosperm boundary near the aleurone layer. These structures had higher degree of elasticity (DE) compared to the inner endosperm (0.5–0.6 mm). Besides wheat class and specific structures of the caryopsis, moisture content is a prominent factor affecting the mechanical strength of kernels. Stress relaxation tests show that bread wheat kernels with 69.2% DE at 13% moisture decreased to 31.6% DE with additional 6% moisture content. Soft wheat kernels DE of 61.0% at 13% moisture decreased to 22.7% at 19.7% moisture. Stress relaxation revealed pronounced time‐dependence. However, the differences of stress values at 120–180 sec were not significant in all wheat classes and moisture contents evaluated. The stress values after 120 sec might be attributed to the elastic deformation of the kernels. 相似文献
104.
Saulo da Luz e Silva Paulo Roberto Leme Soraia Marques Putrino Anglica Simone Cravo Pereira Amaury Camilo Valinote Jos Carlos Machado Nogueira Filho Dante Pazzanese Duarte Lanna 《Livestock Science》2009,122(2-3):290-295
The purpose of this work was to evaluate the fatty acid composition of the Longissimus muscle from carcasses of Nellore steers fed diets with calcium salts of fatty acids (CSFA) and high moisture corn. Forty eight steers were fed during 70 days four diets containing dry corn (DC), high moisture corn (HM), dry corn plus CSFA (DC-CSFA) or high moisture corn plus CSFA (HM-CSFA). Fatty acid composition of the Longissimus muscle was determined by gas chromatography. Corn type had no effect on the ether extract percentage and in the content of the majority of the fatty acids, although steers fed HMC showed higher levels of polyunsaturated fatty acids and polyunsaturated/saturated ratio. Feeding CSFA increased ether extract percentage but had no effect on total of saturated, unsaturated and saturated: unsaturated ratio. Both high moisture corn and calcium salts of fatty acids increased CLA (cis9, trans11) and total CLA concentrations in intramuscular fat. 相似文献
105.
The distribution of FCoV Types I and II in a Portuguese cat population was studied by a RT-PCR assay targeting the 3′-end of the viral RNA. For a period of 3 years, 120 samples were collected and 57 were found positive for FCoV RNA. Within the positive samples the presence of FCoV Type I was found in 79%. Type II was only detected in 3.5% in animals with Feline Infectious Peritonitis. The remaining 17.5% could not be differentiated. These viral sequences, comprising a region within gene S were further subjected to a heteroduplex mobility assay (HMA) detecting the presence of viral quasispecies in 17% of the samples. Phylogenetic analysis for FCoV Type I revealed high genetic diversity between the Portuguese sequences and other previously characterized strains, while Type II tree showed a higher genetic homogeneity. This study confirmed the presence of FCoV Types I and II circulating in Portugal and detected high genetic diversity between circulating strains suggesting that the virus persists within the host as mixed viral populations. 相似文献
106.
Leandro E. Miranda Giancarlo Coppola Hunter R. Hatcher Matthew B. Jargowsky Zachary S. Moran Michael C. Rhodes 《Fish and Fisheries》2021,22(1):128-140
Reservoirs are mostly managed at local scales as spatially independent units. A basin‐scale perspective may increase awareness at a broader scope and generate insight not evident at local scales. We examined the array of reservoir attributes and fisheries in the Mississippi Basin to identify management opportunities. The basin is the third largest in the world and includes over 1,700 reservoirs >100 ha, the most of any river basin. Our bird's‐eye view shows a piecemeal approach where reservoirs are mostly administered at the local level. Basin‐wide or catchment coordination to holistically address problems that recur across the basin is mostly lacking. A basin‐wide coordination arrangement could facilitate various facets of reservoir management. We reviewed governance arrangements in major river basins across the globe and concluded that the basin‐wide administrative layer we encourage for the Mississippi Basin may already exist in some basins but may not be directly applicable everywhere. 相似文献
107.
The effects of temperature on anatomical and chemical characteristics of Quercus cerris cork were examined. Cork samples were subjected to isothermal air heating between 150 °C and 400 °C and analyzed for mass loss, cellular structure and chemical composition.The thermal decomposition of Q. cerris cork is similar to that of Q. suber cork. Cork is thermally stable below 200 °C and after that degradation depended on temperature and heating time with increasing mass loss, i.e. 3% at 200 °C 10 min and 46% at 350 °C 60 min. With temperature and starting at 200 °C, cells expanded, cell wall thickness was reduced and corrugations were lost.Extractives degraded at lower temperatures, although aliphatic extractives were found to be more stable. Suberin from Q. cerris was more heat resistant than Q. suber suberin, while lignin showed similar resistance.These results provide a basis for studies on the production of Q. cerris bark expanded cork agglomerates for insulation purposes. 相似文献
108.
109.
Márcio Fléquisson Alves Miranda Maria Betânia Galvão dos Santos Freire Brivaldo Gomes Almeida Fernando José Freire Luiz Guilherme Medeiros Pessoa 《Archives of Agronomy and Soil Science》2018,64(9):1207-1221
This study aimed to evaluate the use of phytoremediation and soil conditioners in the recovery of physical attributes of a saline-sodic Fluvic Neossol in Brazil Northeast. The applied treatments were: Atriplex nummularia L., as phytoremediation plant, due to its ability to extract salts from the soil; organic conditioners, such as bovine and sheep manure; gypsum and polymer, as chemical conditioners. Samples with preserved structure were collected at the time of the experiment installation and 18 months after in the layers 0–10 cm and 10–30 cm. The analyzed attributes were: water dispersed clay, dispersion index, bulk density, penetration resistance, soil porosity, and saturated hydraulic conductivity. The use of sheep manure, gypsum and polymer promoted an increase in saturated hydraulic conductivity in the 0–10 cm layer from 4.51 to 16.37 cm day?1, 11.26 to 23.95 cm day?1 and 7.24 to 22.77 cm day?1, respectively. Gypsum increased the macroporosity in the superficial layer by 42.6%. Atriplex and polymer were more efficient at reducing soil penetration resistance. The polymer was more efficient at improving the physical properties. However, it is necessary to consider phytoremediation with Atriplex as a more sustainable alternative that can still be used as complementary fodder in animal feed. 相似文献
110.
Early survival of Quercus ilex subspecies from different populations after infections and co‐infections by multiple Phytophthora species 下载免费PDF全文
T. Corcobado J. J. Miranda‐Torres J. Martín‐García T. Jung A. Solla 《Plant pathology》2017,66(5):792-804
Forests in Europe are threatened by increased diversity of Phytophthora species, but effects on trees of simultaneous infections by Phytophthora and ecological consequences of their coexistence are unknown. This study explored variation in early survival of Quercus ilex to Phytophthora infections and assessed interactions between Phytophthora species when trees were co‐infected. Three Phytophthora species (P. cinnamomi, P. gonapodyides and P. quercina), seeds from 16 populations of Q. ilex (ballota and ilex subspecies) and two infection times were used as sources of variation in two experiments. The influence of Phytophthora species, Q. ilex subspecies and populations on plant germination and survival were analysed using generalized linear mixed models and survival analysis techniques. Germination rates were not influenced by Phytophthora spp. (P = 0.194) but by the subspecies and populations of Q. ilex (P < 0.001). In Phytophthora‐infested soils, Q. ilex subsp. ilex germinated at higher rates than Q. ilex subsp. ballota. Plant survival was strongly influenced by Phytophthora species (P < 0.001), not by the subspecies and populations of Q. ilex. Seedling mortality was reduced and delayed if a less virulent Phytophthora species infected plants prior to infection by a more virulent Phytophthora species. The results help to explain oak decline syndrome and the lack of natural and artificial regeneration of Q. ilex forests. Lack of interspecific variability of early survival to Phytophthora spp. discourages direct sowing for artificial reforestation programmes. Large, thick seeds, giving plants rapid growth, are advantageous traits when soils are infested with Phytophthora spp. 相似文献