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211.
Biomass and Sterol Production from Vegetal Substrate Fermentation Using Agaricus brasiliensis 下载免费PDF全文
212.
High‐fat diet induces endothelial dysfunction through a down‐regulation of the endothelial AMPK–PI3K–Akt–eNOS pathway 下载免费PDF全文
213.
Carolina Griebeler Gianluca Tondi Thomas Schnabel Carmen Iglesias Sergio Ruiz 《Holz als Roh- und Werkstoff》2018,76(5):1495-1504
A new method that consists of combining wood pre-grading by surface colour followed by the application of homogeneity thermal treatments is proposed to reduce the surface colour variability of the thermally modified blue gum wood. To identify the conditions of the homogeneity thermal treatment for two pre-graded groups with different initial surface colours (pinkish and yellowish), the effects of applying 25 different thermal treatment intensities to such groups were analysed. The effects of this method on mass loss and volumetric swelling were also analysed. Results show that an optical pre-grading of the wood samples and treatments under different conditions can reduce the colour variability of the blue gum wood samples, as well as the volumetric swelling. Mass loss was not homogenised after the treatment, but the difference of masses between the two groups was similar to their untreated state. The application of this new methodology may be of interest for the sawn timber industry to bring more uniform boards on the markets and to promote Eucalyptus globulus as a price-competitive and sustainable alternative timber. 相似文献
214.
Lactobacilli, often used as effectors of host functions, could play an important role in maintaining human health by controlling other intestinal microorganisms capable of producing harmful effects. Using an experimental model, we studied the effect of different oral doses of Lactobacillus casei on the secretory IgA response and the protective capacity of the microorganism in preventing intestinal infections. The optimization of the protective dose of Lb. casei by previous feeding and the use of the lactobacillus as an immunological way to control enteric infections were investigated. We found that conventional mice were protected against infection with Salmonella typhimurium and Escherichia coli by previous feeding for 2 consecutive days with a daily Lb. casei dose of 1.2 x 10(9) cfu/mouse. Previous feeding for 7 d proved less effective, and feeding for 5 d afforded no protection at all. We were also able to demonstrate that the protective effect of Lb. casei against Sal. typhimurium and Esch. coli was connected mainly with the high level of IgA antipathogen antibodies present in intestinal secretions. beta-Glucuronidase (EC 3.2.1.31) and beta-galactosidase (EC 3.2.1.23) activities, measured both in the intestinal fluid and histological samples, showed a marked increase in intestinal inflammatory response on day 5 of feeding. These results show that Lb. casei plays an important role in the prevention of enteric infections, a low dose being enough for protection against intestinal infections by increasing IgA secretion into the intestinal lumen, thus providing adequate defences for the mucosal surface. A previously administered dose of this magnitude could therefore be used as an oral adjuvant in preventing enteric infections. 相似文献
215.
The use of ethanol and bioethanol demonstrates the viability of alternative fuels to gasoline with optimum energy purposes. The development of suitable catalysts is fundamental to improve the electrical performance in Direct Alcohol Fuel Cells (DAFCs). For that reason, a series of amorphous Ni59Nb40Pt0.6Y0.2Z0.2 (PtYZ) alloys adding three different transition metals (Y, Z = Cu, Ru and Sn) were manufactured by Mechanical Alloying (MA) method. The low amount of Pt and bifunctional-electronic role of cocatalysts was analyzed using electrochemical techniques such as Cyclic Voltammetry (CV), chronoamperometry and CO stripping experiments. Concerning to reactivity towards alcohol electrooxidations, alloys with Cu showed the best catalytic performance. However, its use is limited by Cu dissolution in acid media. The PtYZ catalysts showed higher CO tolerance, achieving smaller rates of poisoning (δ) for PtRuSn alloy. CO stripping reveals that CO oxidation on alloys with Ru takes place at lower electrode potentials. The experimental results showed better electric performance, but higher poisoning of the catalytic surface for bioethanol electrooxidation. Acetaldehyde and formic acid were found in bioethanol by HPLC, influencing the electrochemical response. 相似文献
216.
217.
Effect of montmorillonite clay addition on the morphological and physical properties of Jatropha curcas L. and Glycine max L. protein concentrate films 下载免费PDF全文
Alex Osorio‐Ruiz Javier Solorza‐Feria Bor‐Sen Chiou Delilah F. Wood Tina G. Williams Roberto J. Avena‐Bustillos Alma‐Leticia Martínez‐Ayala 《应用聚合物科学杂志》2017,134(7)
Protein concentrates from jatropha (JPC) and soy seeds (SPC) were obtained by solubilization and acid precipitation of proteins. JPC and SPC films were prepared by the casting method, using two different montmorillonite (MMT) clay concentrations and plasticized with glycerol. Film properties were evaluated by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy, thermogravimetric analysis, tensile properties, water retention, and water vapor transmission rate (WVRT). Typical tactoid microcomposite structures were found to be heterogeneously dispersed in the films containing MMT. A small XRD peak was found in films with MMT. Slight improvements in thermal stability and tensile strength were observed in the films with MMT. Reductions in water retention and WVRT were obtained when MMT was added into the films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44459. 相似文献
218.
The effects of fibre type (wheat bran, oat bran, cellulose microcrystalline), size (50, 80, 250 μm) and percentage of substitution (0%, 12%, 24%, 36%) on batter and layer cake characteristics were determined. Batter density, and the rheological parameters (G′ and G″) increased with fibre size, but the flow index decreased. Especially with 20% wheat bran, large-sized fibre gave the most firm, chewy and yellow cakes, while providing the most significant sensory differences with the control. Cakes with microcrystalline cellulose were the most similar to the control. All cakes obtained high sensory scores, indicating that they were not disagreeable for consumers. It is possible to obtain high quality cakes when adding up to 20% of fibre, but selection of an adequate fibre is necessary. 相似文献
219.
Fernando de la Peña Moreno Gracia Patricia Blanch Gema Flores María Luisa Ruiz del Castillo 《Journal of the science of food and agriculture》2010,90(6):989-994
BACKGROUND: Although strawberry aroma is very complex, certain compounds have been described as main contributors, i.e. furanones, aldehydes, alcohols, sulfur compounds and particularly methyl and ethyl esters. In addition, strawberries possess potent antioxidant activity because of their high content of phenolic compounds. Among them, flavonols are highlighted as important antioxidant compounds in strawberry. The objective of this study was to assess the effect of methyl jasmonate (MJ) on the composition of the major contributors to aroma and on the content of certain flavonols in strawberry fruits. RESULTS: The levels of all studied volatile compounds were significantly affected by MJ treatment, though the individual effect differed according to the specific compound considered. Most of them increased significantly (P < 0.05), except methyl butanoate, which always showed higher levels in untreated strawberries. In contrast to aroma compounds, the change in the concentration of flavonols (i.e. myricetin, quercetin and kaempferol) was not significant in MJ‐treated strawberries. Considering the health‐promoting activity of these compounds, further investigations on the experimental conditions related to the treatment are required to control flavonol bioformation by means of MJ. CONCLUSION: The exogenous application of MJ vapour to strawberry enhances, in general, the production of the most relevant aroma‐active compounds. On the contrary, MJ treatment does not appear to influence the levels of myricetin, quercetin and kaempferol. Thus postharvest MJ treatment is proposed as an approach to obtain improved strawberry fruits in terms of sensory quality and health‐promoting properties. Copyright © 2010 Society of Chemical Industry 相似文献
220.
Roxanna B. Alvarez M.F. Horstemeyer Neil Williams Augusto Ruiz 《Corrosion Science》2010,52(5):1635-1648
Pit initiation, growth, and coalescence corrosion mechanisms of an AE44 magnesium alloy subjected to a salt-water environment were quantified. Stereological quantities were evaluated using optical microscopy, scanning electron microscopy, and laser beam profilometry. Three corrosion mechanisms clearly arose: pitting, intergranular, and general. Pitting began as the result of localized galvanic dissolution between the intermetallics and magnesium matrix. Intergranular corrosion arose as pits coalesced. General corrosion arose by dissolution and regeneration of a Mg(OH)2 film at a continuous rate. Stereological quantification demonstrated that the corrosion pit number density and pit radius size distribution initially increased before decreasing due to pit coalescence. 相似文献