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排序方式: 共有435条查询结果,搜索用时 12 毫秒
91.
Coimbra MA Gonçalves F Barros AS Delgadillo I 《Journal of agricultural and food chemistry》2002,50(12):3405-3411
Monovarietal white wines from Maria Gomes and Bical Portuguese Bairrada varieties were prepared according to different maceration and pectic enzyme clarification procedures. The polysaccharide-rich extracts, obtained by wine concentration, dialysis, and lyophilization, were fractionated by graded ethanol precipitation. A wide range of fractions rich in polysaccharides were obtained. Using the spectral region between 1200 and 800 cm(-)(1) of the FTIR spectra of the wine polysaccharide dry extracts, using PCA and CCA chemometric methods, it was possible to discriminate the extracts on the basis of their polysaccharide composition. Moreover, it was possible to identify the wine-making processes involved and their influence on the wine polysaccharides. Furthermore, a calibration model using a PLS1 was proposed for the quantification of mannose in the samples obtained by precipitation with 60% ethanol aqueous solutions. This information will allow an expeditious assessment and monitoring of the polysaccharide composition and modifications that occur during the wine-making processing and evolution. 相似文献
92.
Effects of conservation treatment and cooking on the chemical composition and antioxidant activity of Portuguese wild edible mushrooms 总被引:2,自引:0,他引:2
Barros L Baptista P Correia DM Morais JS Ferreira IC 《Journal of agricultural and food chemistry》2007,55(12):4781-4788
The effects of processing and cooking practices on the chemical composition and antioxidant activity of Portuguese wild edible mushroom species (Lactarius deliciosus, Macrolepiota mastoidea, Macrolepiota procera, and Sarcodon imbricatus) were investigated. Dried, frozen, and cooked samples were analyzed for proximate constituents (moisture, fat, crude protein, ash, and carbohydrates) and nutritional value. Fatty acid and sugar profiles were also obtained by gas-liquid chromatography/flame ionization detection and high-performance liquid chromatography/refraction index, respectively. The antioxidant properties were evaluated by several biochemical assays: 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity, reducing power, inhibition of beta-carotene bleaching, and inhibition of lipid peroxidation in brain tissue using thiobarbituric acid reactive substances. Results of this study show that mushroom species and processing and cooking practices are all effective determinants for either chemical composition or antioxidant properties. Cooked samples proved to have lower nutrient concentrations and lower antioxidant activities than either dried or frozen samples. In what concerns fatty acids and sugar individual profiles, only cooking proved to be relevant: The cooked samples presented higher monounsaturated fatty acid and lower polyunsaturated fatty acid and sugars contents. 相似文献
93.
The effects induced by cooking, dry heating, popping, fermentation and germination on sorghum proteins were studied. Changes promoted by these processing methods were compared via sodium dodecyl sulfate polycrylamide gel electrophoresis (SDS-PAGE), in vitro protein digestibility (IVPD) assay and Fourier Transform Infrared (FT-IR). 相似文献
94.
Several experiments were performed examining the effect of different culture variables on the growth and survival of Argopecten nucleus and Nodipecten nodosus larvae. Higher growth and survival values were obtained at a low density (1 larvae mL?1) than at a high density (5 larvae mL?1), except for N. nodosus's survival, which was not affected by density. Higher growth was obtained when feeding the larvae a diet of Isochrysis galbana, similar results occurred with the diet of Isochrysis galbana+Chaetoceros calcitrans in A. nucleus and with I. galbana combined with the lipid emulsion EmDHA in N. nodosus. Higher survival was obtained when the diet included a mixture of microalgae than when EmDHA was supplemented. Growth and survival of the larvae of A. nucleus were greater when fed continuously, while N. nodosus grew and survived better when food was given discontinuously. Higher growth and survival values were recorded at lower food concentrations ranging from 20 to 40 cells μL?1 of I. galbana. Higher growth was observed with increasing temperature between 22 and 28 °C, although there was a simultaneous decrease in survival. No significant effects on larval production parameters were found when the culture water was changed totally or partially, but higher larval growth of N. nodosus was verified when a partial renewal of water was performed. 相似文献
95.
Molecular characterization and confocal laser scanning microscopic study of Pygidiopsis macrostomum (Trematoda: Heterophyidae) parasites of guppies Poecilia vivipara 下载免费PDF全文
J N Borges V S Costa C Mantovani E Barros E G N Santos C L Mafra C P Santos 《Journal of fish diseases》2017,40(2):191-203
Pygidiopsis macrostomum and Ascocotyle (Phagicola) pindoramensis (Digenea: Heterophyidae) parasitize guppies as intermediate hosts and, respectively, fish‐eating mammals or birds as definitive hosts. Heterophyids have zoonotic potential, and molecular studies associated with morphological and ecological aspects have helped to clarify their taxonomy and phylogeny. Poecilia vivipara naturally parasitized by metacercariae of both species (100% prevalence) exhibit no external signs of parasitism. In this work, four new sequences of P. macrostomum (18S rDNA, 28S rDNA and ITS2 rDNA) and one new sequence of A. (P.) pindoramensis (mtDNA cox‐1) are presented. Phylogeny reconstructions linked P. macrostomum to other heterophyids, but the separation of the Heterophyidae and Opisthorchiidae remains unclear. Additionally, we used indirect immunocytochemistry and the phalloidin‐fluorescence techniques allied with confocal laser scanning microscopy to describe muscular and neuronal structures of P. macrostomum. A complex arrangement of muscular fibres is associated with the tegument, suckers, gut and reproductive system. Radial fibres around the ventral sucker are thick, branched and extend to the body wall. High‐resolution confocal imaging revealed a typical digenean muscular arrangement and important heterophyid morphological traits. These data will support future control measures to reduce the parasitism in guppies reared in fish farming systems, especially for aquarium and experimental purposes. 相似文献
96.
Geraldo Stachetti Rodrigues Inacio de Barros Eugène Ejolle Ehabe Patrick Sama Lang Frank Enjalric 《Agroforestry Systems》2009,77(1):9-22
Farming Systems developed in Humid Tropical Zones are frequently characterized by a combination of perennial and annual plants,
intermixed in complex tree-crop associations. The productive functioning, the agronomic and economic performances, and the
sustainability of these crop associations remain poorly understood. To improve the management capacity of these complex agroforestry
systems, adequate indicators must be developed and integrated in assessment systems. These may then be used to aid farmers,
assisted by their extension agents, in making decisions regarding management practices. The present study focused on the agroforestry
systems developed by 38 farmers in the South West Region of Cameroon, which were surveyed for a large set of variables, aiming
at formulating a Traditional Agroforestry Performance Indicators System (TAPIS). Analyses of the relationships among indicators
in TAPIS allowed an improved understanding of agro-ecological and agro-economic performances in the studied plots, revealed
tradeoffs regarding plant stand, income generation, food production, input demands and work requirements; and may contribute
to the sustainability assessment of agroforestry systems. 相似文献
97.
Schubach TM Schubach A Okamoto T Pellon IV Fialho-Monteiro PC Reis RS Barros MB Andrade-Perez M Wanke B 《The Journal of small animal practice》2003,44(9):395-398
The recovery of Sporothrix schenckii from blood samples is rare, and the diagnosis of systemic sporotrichosis is usually made at necropsy. In this report, S schenckii was isolated from two or more internal organs of nine necropsied cats with naturally acquired sporotrichosis. Haematogenous spread was demonstrated in vivo by the isolation of S schenckii from the peripheral blood of 17 (n = 49, 34.4 per cent) cats. Feline leukaemia virus (FeLV) was not detected, and co-infection with feline immunodeficiency virus (FIV), observed in nine cases (n = 43, 20.9 per cent), apparently did not affect the isolation of S schenckii from peripheral blood or from the internal organs. 相似文献
98.
F. M. Da Matta M. Maestri R. S. Barros A. J. Regazzi 《The Journal of Horticultural Science and Biotechnology》2013,88(5):741-746
Coffee plants of five Arabica and one Canephora genotypes were raised in containers with 0.02 nr1 of soil, under a clear plastic shelter. When they were 18 months old, irrigation was withheld until the first signs of wilting appeared. This occurred four to five days after withholding irrigation, when the pre-dawn water potential of young fully expanded leaves of the plagiotropic branches was about -2.4 MPa. Control plants remained under daily irrigation. The pressure-volume technique was used to estimate volume averaged water relations properties of sample leaves. The turgor loss point was approximately -1.6 MPa for control plants and -2.0 MPa for stressed plants, an osmotic adjustment of approximately 22%. The Canephora genotype showed a slightly higher adjustment. The relative water content at the turgor loss point remained at approximately 93%, irrespective of genotype or treatment. The maximum bulk modulus of elasticity did not change significantly with water deficit, remaining at about 24 MPa, except for a slight increase in the Canephora genotype. The specific leaf area of the Arabica genotypes decreased about 20%, as compared with a 10% decrease for the Canephora genotype. 相似文献
99.
100.
M.V. Maciel S.M. Morais C.M.L. Bevilaqua R.A. Silva R.S. Barros R.N. Sousa L.C. Sousa E.S. Brito M.A. Souza-Neto 《Veterinary parasitology》2010
The chemical composition of essential oils from three species of plants belonging to the Eucalyptus genus was determined and, their insecticidal effects on egg, larva and adult phases of Lutzomyia longipalpis were assessed. The insects were collected in the municipality of Sobral in the State of Ceará, Brazil. Five treatments with different concentrations were performed along with two negative controls, distilled water and Tween 80 (3%), and a positive control, cypermethrin (0.196 mg/ml). The tests were carried out in plastic pots internally coated with sterile plaster and filled with a substrate made of rabbit feces and crushed cassava leaves. The eggs, larvae and adults were sprayed with the oils. The hatched larvae were counted for 10 consecutive days and observed until pupation. Insect mortality was observed after 24, 48 and 72 h. E. staigeriana oil was the most effective on all three phases of the insect, followed by E. citriodora and E. globulus oils, respectively. The major constituents of the oils were Z-citral and alpha-citral (E. staigeriana), citronellal (E. citriodora) and 1,8-cineole (E. globulus). The Eucalyptus essential oils constitute alternative natural products for the control of L. longipalpis since the median effective concentration (EC50) values revealed relevant action as compared with other natural products, some of their chemical constituents are already known for their insecticidal activity and these oils are produced in commercial scale in Brazil. 相似文献