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51.
The aim of this research was to optimize mixtures of fibers from different sources and degree of processing meeting acceptable dough viscometric standards to design low‐calorie wheat bread formulations. Effects of soluble (inuline [FN]), partially soluble (sugar beet [FX]), pea cell wall (SW), and insoluble (pea hull [EX]) dietary fibers on wheat dough pasting and gelling profiles have been investigated. Impact of fibers added singly and in associated mixtures at different levels on the investigated viscometric parameters retrieved from a Rapid Visco Analyser curve has been assessed by response surface methodology, and the thermal parameters derived from the cooking and cooling functional profile were correlated. Flour replacement up to 34% by fibers significantly provided a deleterious effect on pasting and gelling viscosity profiles of the resulting hydrated high fiber‐flour blends. The magnitude of the reduction in dough viscometric characteristics during gelatinization, pasting, and setback closely depended on the nature of the fibers in the blend and on the extent of the flour substitution. A delayed and restricted swelling of starch granules and amylose leaching process preferentially achieved by the pair FN‐FX resulted in higher pasting temperatures and reduced peak viscosities during cooking and a sharp decrease of the setback on cooling. Single addition of FX, FN, and EX, respectively, provided a significant decrease in both breakdown viscosity and viscosity at the end of 95°C. Simultaneous presence of FN and EX that exhibit medium or low hydration properties allowed a partial restoration of initial breakdown viscosity and a simultaneous decrease in holding strength. Caution should be paid to the pairs FN‐FX and EX‐SW because of the adverse extra decline they induced in the viscosities of both hot paste and cold gel. 相似文献
52.
53.
Porres JM Aranda P López-Jurado M Urbano G 《Journal of agricultural and food chemistry》2007,55(18):7445-7452
The protein and mineral composition of different varieties of three different lupin species (Lupinus albus, Lupinus angustifolius, and Lupinus luteus) and the effect of alpha-galactoside removal by means of a hydroalcoholic extraction process on such composition were studied in relationship to nutrient distribution among the different anatomical parts of the seed (embryo, cotyledon, and seed coat). The extent of processing-derived protein insolubilization was assessed by both chemical and electrophoretic techniques and related to the amount of nitrogen soluble in H(2)O, NaCl, ethanol, NaOH, and sodium dodecyl sulfate/beta-mercaptoethanol (SDS/BME). The alpha-galactoside extraction process caused a significant increase in the amount of total and insoluble nitrogen and decreased the amount of soluble protein nitrogen, without affecting the content of soluble nonprotein nitrogen. alpha-Galactoside extraction was not effective at decreasing the levels of Mn present in lupins, and processing caused an increase in the content of this mineral in all of the species studied with the exception of L. albus var. multolupa. In general, the effect of processing on mineral content varied with the different lupin species, and mineral losses were lower in L. luteus. 相似文献
54.
55.
Pimentel Dde S Ramos CA Ramos RA de Araújo FR Borba ML Faustino MA Alves LC 《Veterinary parasitology》2012,185(2-4):286-289
This paper describes an outbreak of Trypanosoma vivax for the first time in the state of Pernambuco, Brazil, affecting dairy cattle in the municipality of Itambé in the northern coastal zone of the state. Clinical signs compatible with infection by blood protozoa and epidemic miscarriages were observed. The diagnosis of T. vivax was confirmed through biometric microscopy and molecular analysis with PCR and DNA sequencing. The T. vivax isolate detected in the present study proved to be genetically very close to other Brazilian isolates of the protozoan despite being geographically distant. 相似文献
56.
Hernández DM Díaz-Ruiz G Rivero-Cruz BE Bye RA Aguilar MI Rivero-Cruz JF 《Fitoterapia》2012,83(3):527-531
From the roots of Iostephane heterophylla, six known compounds, namely, ent-trachyloban-19-oic acid (1), the mixture of ent-kaur-16-en-19-oic acid (2) and ent-beyer-15-en-19-oic acid (3), xanthorrhizol (4), 16α-hydroxy-ent-kaurane (5) and 16α-hydroxy-ent-kaur-11-en-19-oic acid (6) were isolated using a bioassay-guided fractionation method. The known compounds (1-6) were identified by comparison of their spectroscopic data with reported values in the literature. In an attempt to increase the resultant antimicrobial activity of 1 and 4, a series of reactions was performed on ent-trachyloban-19-oic acid (1) and xanthorrhizol (4), to obtain derivatives 1a, 1b, and 4a-4d. All the isolated compounds (1-6) and the derivatives 1a, 1b, and 4a-4d were evaluated for their antimicrobial activity against two oral pathogens, Streptococcus mutans and Porphyromonas gingivalis associated with caries and periodontal disease, respectively. Compounds 1, 1b, 2+3, 4 and 4d inhibited the growth of S. mutans with concentrations ranging from 4.1 μg/mL to 70.5 μg/mL. No significant activity was found on P. gingivalis except for 4 with an MIC of 6.8 μg/mL. The ability of 1, 1b, 2+3, 4 and 4d to inhibit biofilm formation by S. mutans was evaluated. It was found that 1, 1b, 4 and 4d interfered with the establishment of S. mutans biofilms, inhibiting their development at 32.5, 125.0, 14.1 and 24.4 μg/mL, respectively. 相似文献
57.
58.
Lucia Lioi Incoronata Galasso Maria Gloria Daminati Angela Rosa Piergiovanni 《Genetic Resources and Crop Evolution》2010,57(4):533-542
The primary structure of the double-headed Bowman-Birk inhibitor (BBI) family and the antitryptic activity were investigated
in cultivated and wild Phaseolus species. Two BBI types were identified; the first one inhibits trypsin and chymotrypsin (tc-BBI), the second one elastase
and trypsin (et-BBI). Only tc-BBI was found in P. lunatus and P. parvulus, while none of BBI types, identified in this study, was found in P.
leptostachyus. The deduced amino acid sequences revealed some polymorphisms within both tc-BBI and et-BBI binding loops that could affect
the inhibitory activity. The trypsin inhibitor content showed a high variation with the lowest value recorded in P. lepthostachyus and the highest one observed in P. oligospermus. Southern blot analysis confirmed the absence of both BBI types in P. leptostachyus and suggests that in P. coccineus, P. dumosus and P. costaricensis, the two genes were clustered in a narrow genomic region of 1.3 kbp. 相似文献
59.
Eleonora Bonifacio Gloria Falsone Stefania Piazza 《Journal of Soils and Sediments》2010,10(8):1475-1486
Purpose
In soils from serpentinitic areas the natural background of Ni and Cr is so high that the assessment of contamination by comparing metal concentrations with some fixed thresholds may give unreliable results. We therefore sought a quantitative relation between serpentines and Ni and Cr concentrations in uncontaminated soils, evaluated if the approach may help in establishing a baseline, and discussed if additional anthropogenic inputs of Ni and Cr can be realistically individuated in these areas.Materials and methods
We analysed the total, acid-extractable and exchangeable concentrations of Ni and the total and acid-extractable concentrations of Cr in 66 soil horizons, belonging to 19 poorly developed and uncontaminated Alpine soils. The soils had different amounts of serpentines, depending on the abundance of these minerals in the parent material. We calculated an index of abundance of serpentines in the clay fraction by XRD and related total metal contents to the mineralogical index. We then tested the regressions on potentially contaminated soils, developed on the alluvial plain of the same watershed.Results and discussion
We found extremely high total concentrations of Ni (up to 1,887 mg kg–1) and Cr (up to 2,218 mg kg–1) in the uncontaminated soils, but only a small proportion was extractable. Total Ni and Cr contents were significantly related to serpentine abundance (r 2?=?0.86 and 0.74, respectively). The regressions indicated that even small amounts of serpentines induced metal contents above 200 mg kg–1, and the 95% confidence limits were 75 and 111 mg kg–1 of Ni and Cr, respectively. When the regressions were tested on the potentially contaminated soils, a good estimate was obtained for Cr, while the Ni concentration was overestimated, probably because of some leaching of this element.Conclusions
The concentrations of Ni and Cr that can be expected in soils because of the presence of small amounts of serpentines are comparable to the amounts accumulated in the soil because of diffuse contamination and potentially contaminated soils had metal concentrations falling in the range expected from the presence of natural sources. Only in the case of very severe contamination events, the identification of anthropogenic sources adding to the natural background would be feasible. 相似文献60.
Live BW and BCS data were collected from 2,775 breeding rabbits (644 males and 2,131 females) of 34 genetic types and sorted according to their specialization (maternal, paternal, and others). Data were gathered on 66 visits to 43 commercial farms in Spain between 2009 and 2011. Mean BW was 4.72 kg (range of 2.87 to 8.13 kg, with a median BW of 4.60 kg) and mean BCS was 4.6 (range of 1.0 to 9.0, with a median BCS of 5.0). females had heavier (P < 0.05) BW than males and paternal lines of rabbits had greater (P < 0.05) BW than maternal lines and other breeds/lines not selected for meat production. Between 69.3% and 75.4% of the rabbits were deemed healthy by a veterinarian and, as expected, healthy rabbits were heavier (P < 0.05) than sick rabbits diagnosed with rhinitis, mastitis, sore hocks, and several other diseases. Among purebred, maternal lines of rabbits, Hyplus GD24, UPV A, and UPV V were heavier (P < 0.05) than hyplus GD14 and Hyla HL-D lines, and line UPV R had the greatest (P < 0.05) BW among the purebred, paternal lines. Additionally, A×H, A×V, PS19, and P×A crossbreds had greater (P < 0.05) BW than HE-C×D, HL-C×D, H×V, LP×V, and V×P crossbreds among the maternal lines, whereas HE-SL were the heaviest (P < 0.05) crossbred paternal line of rabbits. Additionally, females received greater (P < 0.05) BCS than males and BCS were greater (P < 0.05) in healthy than sick rabbits. Moreover, maternal lines had smaller (P < 0.05) BCS than either paternal lines or other lines/breeds not selected for meat production. Results also indicated a moderate relationship between BCS and BW (r = 0.32), with a 1-point change in BCS equivalent to an ~ 245-g change in BW. results from this study can be used as baseline figures for breeding rabbits in spain and are essential factors in several decisions concerning housing, feeding, reproduction, health, and welfare of breeding rabbits. 相似文献