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41.
42.
Cristina Jansen-Alves Karina F. Fernandes Michele M. Crizel-Cardozo Fernanda D. Krumreich Caroline D. Borges Rui C. Zambiazi 《Food and Bioprocess Technology》2018,11(7):1422-1436
Propolis presents several health benefits due to the presence of bioactive compounds, mainly phenolic compounds; however, its application in food is limited due to undesirable odor and low water solubility. The bioactive compounds are usually susceptible to degradation by exposure to light, heat, or oxygen or by interaction with other compounds, which may limit its biological activity. The study aimed the propolis extract microencapsulation using rice, pea, soybean, and ovoalbumin proteins as wall material by spray drying and to analyze their in vitro digestion. The propolis extract presented a high concentration of apigenin. Encapsulation efficiency was greater than 70%, and it was maintained the antioxidant activity of propolis (88% inhibition of DPPH for propolis extract and >?73% for the microparticles). The DSC, ATR-FTIR, and X-ray diffraction techniques confirmed the encapsulation. The microparticles showed different shapes, sizes, and physical characteristics. The microparticles encapsulated with pea protein could be used in formulations of Minas Frescal cheese due to the controlled released, whereas the other microparticles could be used in pudding formulations. 相似文献
43.
Rafael A. Amaral Cristiano P. Borges Alberto C. Habert Nicolas R. J.‐D. Mermier 《化学工程与技术》2016,39(6):1171-1176
Emission of sulfur compounds to the atmosphere is universally recognized as one key target to be reduced. For membrane pervaporation which is considered as a potential purification process of fuels, dual‐layer polyurethane (PU)/polyethersulfone hollow‐fiber membranes were prepared. A novel fabrication technique is proposed using a quadruple spinneret to produce the fiber with such morphology by simultaneous spinning of two polymer solutions in the presence of two corresponding precipitation media. Activated carbon was added into the PU solution to improve the transport properties of the selective layer. Resulting hollow‐fiber membranes showed very good adhesion between the selective layer and its support, in addition to an effective removal of a sulfur compound such as 2‐methyl thiophene from a typical model fuel, an indication of good prospects for both the fabrication technique and for sulfur removal by pervaporation of fuels. 相似文献
44.
45.
Dayana Pereira de Andrade Cíntia Lacerda Ramos Diego Alvarenga Botrel Soraia Vilela Borges Rosane Freitas Schwan Disney Ribeiro Dias 《International Journal of Food Science & Technology》2019,54(7):2355-2362
The probiotic strains Lactobacillus brevis CCMA1284 and Lactobacillus plantarum CCMA0359 were microencapsulated by spray drying using different matrices – whey powder (W), whey powder with inulin (WI) and whey powder with maltodextrin (WM). Viability of the microencapsulated strains in acid and bile juices and during 90 days of storage (seven and 25 °C) was evaluated. The two strains exhibited high encapsulation efficiency (> 86%) by spray drying. The different matrices maintained L. plantarum viability above six log CFU g−1 at 7 °C for 90 days, whereas similar results for L. brevis were observed only for W. The use of inulin as matrix of encapsulation did not enhance bacterial viability in the evaluated conditions. In general, the use of W and WM as matrices was effective for L. plantarum viability. However, only W was effective for L. brevis in the evaluated conditions. The spray drying technique was successfully adopted for the encapsulation of L. plantarum CCMA0359 and L. brevis CCMA1284 strains. 相似文献
46.
A feasibility study of Lactobacillus plantarum in fruit powders after processing and storage
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Sandra Borges Joana Barbosa Joana Silva Ana M. Gomes Manuela Pintado Cristina L. M. Silva Alcina M. M. B. Morais Paula Teixeira 《International Journal of Food Science & Technology》2016,51(2):381-388
The aim of this study was to develop fruit powders (apple, banana and strawberry) enriched with a probiotic strain (Lactobacillus plantarum 299v). Two methodologies were proposed: (i) drying of the fruit with probiotic culture incorporated (by convection) or (ii) drying of fruit (by convection) and addition of spray‐dried probiotic culture. In the first methodology, processing caused a notable reduction in probiotic viable counts in apple, but this reduction was lower during drying of banana and strawberry. A large reduction in viable cells was also recorded during storage. In the second methodology, the survival of L. plantarum 299v was considerably higher during spray‐drying, and fruit powders with a microbial content suitable for a probiotic food (108–109 cfu g?1) were obtained. The fruit powders incorporating L. plantarum 299v can be stored at 4 °C or at room temperature, for at least 3 months. This preliminary study demonstrated that fruit powders are good carriers of probiotic cultures, but the techniques used to produce them should be carefully considered. 相似文献
47.
Davide Anghinolfi Giorgio Cannata Fulvio Mastrogiovanni Cristiano Nattero Massimo Paolucci 《Computers & Operations Research》2012
This paper faces the problem of optimizing the wiring and the connections in a tactile skin for robots. The robotic skin is a device composed of a network of tactile sensors, whose wiring can be very complex: the control of this complexity is a key problem. In the considered robotic skin, skin elements are grouped into skin patches, which output tactile data that have to be read by a micro-controller. The logical connections between the sensors must be defined in order to route signals through the network. A finite set of micro-controllers is given and a set of constraints is imposed on the given assignment and routing. The considered problem has a combinatorial nature and it can be formulated as a Minimum Constrained Spanning Forest problem with costs on arcs that cannot be a priori defined as they are solution-dependent. The problem is NP-hard. The paper introduces a mathematical formulation and then proposes a Multi-Start Heuristic algorithm and an Ant Colony Optimization approach whose effectiveness is evaluated through experimental tests performed on both real and synthetically generated instances. 相似文献
48.
Ana C. Borges A. Jayakrishnan Pierre-Etienne Bourban Christopher J.G. Plummer Dominique P. Pioletti Jan-Anders E. Månson 《Materials science & engineering. C, Materials for biological applications》2012,32(8):2235-2241
Poly(oxyethylene 20 sorbitan) monolaurate (Tween® 20) methacrylates were synthesized by coupling methacryloyl chloride (MeOCl) to Tween 20 in the presence of 4-(N,N-dimethylamino) pyridine, using THF as a solvent, in order to investigate their suitability as precursors for photopolymerizable hydrogels in tissue engineering applications. The degree of substitution could be controlled by adjusting the molar ratio of MeOCl and Tween 20, giving three different monomers: Tween 20 monomethacrylate, Tween 20 dimethacrylate and Tween 20 trimethacrylate. Combined 1 H NMR and MALDI-TOF MS confirmed these monomers to be of high purity and to have polydispersities less than 1.3. It was shown that aqueous solutions of the monomers were photoactive, all the methacrylate groups reacting within 30 minutes exposure to a UV light intensity of 145 mW/cm2. Aqueous Tween 20 trimethacrylate was then combined with N-vinyl-2-pyrrolidone (NVP), giving tough copolymer hydrogels on photopolymerization, whose swelling ratios and swelling rates could be tuned by varying the Tween 20 trimethacrylate content. The use of a flexible spacer with a multifunctional monomer gives a permanent three-dimensional network, whilst maintaining degrees of swelling of between 60 and 85%, with potential for a wide range of biological and non-biological applications. 相似文献
49.
Renato Bacchetta Paolo Tremolada Cristiano Di Benedetto Nadia Santo Umberto Fascio Giuseppe Chirico Anita Colombo Marina Camatini Paride Mantecca 《Carbon》2012,50(12):4607-4618
Lethal and teratogenic potentials of carbon nanoparticles (CNPs) in their amorphous form were investigated by the standardized Frog Embryo Teratogenesis Assay-Xenopus (FETAX), a 96-h in vitro whole-embryo toxicity test based on the amphibian Xenopus laevis. Embryos were acutely exposed to 1, 10, 100 and 500 mg/L CNP suspensions and evaluated for lethality, malformations and growth inhibition. Larvae were processed for histological and ultrastructural analyses to detect the main affected organs, to look for specific lesions at the subcellular level and to image and track CNPs into tissues. Only the highest CNP suspension resulted in being embryolethal for X. laevis larvae, while malformed larva percentages significantly differed from controls starting from 100 mg/L. The stomach and gut were the preferential CNP accumulation sites, on the contrary, the digestive epithelium remained intact. The analyses showed the presence of isolated nanoparticles and/or aggregates in different secondary target organs. CNPs were found in circulating erythrocytes. The research confirms the good tolerance of X. laevis towards pure elemental carbon in its nanoparticulate amorphous form, but highlights the possibility of CNP transfer toward all body areas. 相似文献
50.
Paulo H. R. Borges Neil B. Milestone Juliana O. Costa Cyril J. Lynsdale Túlio H. Panzera André L. Christophoro 《Materials and Structures》2012,45(5):663-678
Blended cement pastes are currently used for encapsulation of low level and intermediate level nuclear waste in the UK. However,
there is still little information on the long-term durability of those mixes to some chemical attacks. Accelerated testing
may predict the long-term durability or at least help the selection of more durable formulations. In this work, blended blastfurnace
slag (BFS)/Portland cement (OPC) pastes containing 60, 75 and 90% BFS and pulverised fuel ash (PFA)/OPC pastes with 40, 55
and 75% PFA were cured at 20 and 60°C for 90 days then submitted to natural and accelerated carbonation (5% CO2). The effects of the curing temperature as well as the OPC replacement level on the carbonation ratio are presented. Results
showed a good correlation between natural and accelerated carbonation for the pastes studied. Carbonation was found to be
governed by the amount of calcium hydroxide available in the mixes before the process started. 相似文献