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排序方式: 共有3447条查询结果,搜索用时 15 毫秒
91.
María Janeth Rodríguez-Roque María Alejandra Rojas-GraüPedro Elez-Martínez Olga Martín-Belloso 《Food chemistry》2013
The aim of this research was to evaluate changes in the phenolic compounds, isoflavones and antioxidant activity of soymilk following in vitro gastrointestinal digestion (including dialysis). Gastric digestion significantly influenced the release of bioactive substances from the soymilk matrix, increasing the concentration of total phenolic components (35% as the sum of individuals and 14% by Folin–Ciocalteu [F–C] method), total isoflavone content (22%) and total antioxidant activity (76%). The concentration of all those compounds was reduced significantly in the duodenal fraction in comparison to gastric digestion and their lowest concentration was observed in the dialysed fraction, where phenolic acids were not detected. The bioaccessibility of soymilk phenolic compounds was 15% as the sum of individuals and 20% by F–C assay; isoflavones 36% and constituents with antioxidant activity 27%. Results suggest that most of these compounds were sufficiently available to be absorbed and could contribute health benefits. 相似文献
92.
Emilia Ferrer Amparo Alegría Rosaura Farr Pedro Abelln Fernando Romero Gonzalo Clemente 《Journal of the science of food and agriculture》2003,83(5):465-472
The evolution of the Maillard reaction (MR) by measuring the available lysine and furosine (FUR) contents in adapted and follow‐up powdered milk‐based infant formulas over the shelf‐life storage period, at 20 and 37 °C, was studied. Available lysine and FUR contents were determined by fluorimetry and high‐performance liquid chromatography respectively. Statistically significant differences were found between adapted and follow‐up infant formulas with respect to the available lysine and FUR contents. Available lysine contents decreased significantly throughout the storage time, and the contents at 37 °C were lower than at 20 °C. A statistically significant increase in FUR contents was observed during the storage period, with the contents being high at 37 °C than at 20 °C. A simple regression analysis between the available lysine and FUR contents during (a) the first year (b) the second year and (c) the two storage years was applied. The best correlations were obtained during the first year of storage. The results obtained show a clear MR evolution during the storage of infant formulas. Copyright © 2003 Society of Chemical Industry 相似文献
93.
Blanco Massani M Morando PJ Vignolo GM Eisenberg P 《Journal of the science of food and agriculture》2012,92(6):1318-1323
BACKGROUND: Bacteriocins produced by lactic acid bacteria offer enormous promise for food safety preservation. In this study an active multilayer film obtained by the incorporation of lactocin 705 and lactocin AL705, two bacteriocins produced by Lactobacillus curvatus CRL705 with antimicrobial activity against Lactobacillus plantarum CRL691 and Listeria innocua 7, respectively, was characterized for its potential application in active packaging technology. Film activity performance at different storage conditions, bacteriocins transfer into water and sunflower oil, and film surface properties were evaluated. RESULTS: Film activity against L. innocua 7 was maintained during 2, 4 and 6 weeks at 30, 10 and 5 °C respectively. At 30 and 10 °C, activity loss against L. plantarum CRL691 was observed on the second week of storage and after the fourth week at 5 °C. Results showed no significant difference for active multilayer film contact angle and seal properties compared to the control (without bacteriocins). A decrease in lactocin 705 inhibitory activity after sunflower oil contact was observed, while lactocin AL705 remained unaffected. After water contact, film activity was retained for both bacteriocins. CONCLUSIONS: As demonstrated by antimicrobial activity and physico‐mechanical properties retention, lactocin 705 and AL705 active multilayer film present potential for application in active packaging technology. Copyright © 2011 Society of Chemical Industry 相似文献
94.
A comprehensive study of hazelnut oil composition with comparisons to other vegetable oils,particularly olive oil. 总被引:4,自引:0,他引:4
Benitez-Sánchez Pedro Luis León-Camacho Manuel Aparicio Ramón 《European Food Research and Technology》2003,218(1):13-19
Crude and refined hazelnut oils from different countries were characterised by major and minor compounds. Fatty acids, triacylglycerides, waxes, sterols, methyl-sterols, terpenic and aliphatic alcohols, tocopherols, tocotrienols and hydrocarbons were identified and quantified by gas chromatography and high-performance liquid chromatography. The levels of these chemical compounds in hazelnut oils together with the equivalent carbon numbers and triacylglyceride carbon numbers, were compared with the results of analyses of samples of other vegetable oils. The statistical procedure of cluster analysis was used to characterise hazelnut oils versus other edible oils. 相似文献
95.
96.
Cuenca Angel García Pedro Albertos Pedro Salt Julián 《International Journal of Control, Automation and Systems》2011,9(6):1194-1202
International Journal of Control, Automation and Systems - This paper presents a Non-Uniform Predictor-Observer (NUPO) based control approach in order to deal with two of the main problems related... 相似文献
97.
Pedro Gómez-Gasquet Carlos Andrés Francisco-Cruz Lario 《Expert systems with applications》2012,39(9):8095-8107
This paper deals with a variant of flowshop scheduling, namely, the hybrid or flexible flowshop with sequence dependent setup times. This type of flowshop is frequently used in the batch production industry and helps reduce the gap between research and operational use. This scheduling problem is NP-hard and solutions for large problems are based on non-exact methods. An improved genetic algorithm (GA) based on software agent design to minimise the makespan is presented. The paper proposes using an inherent characteristic of software agents to create a new perspective in GA design. To verify the developed metaheuristic, computational experiments are conducted on a well-known benchmark problem dataset. The experimental results show that the proposed metaheuristic outperforms some of the well-known methods and the state-of-art algorithms on the same benchmark problem dataset. 相似文献
98.
The problem of integrating data from multiple data sources—either on the Internet or within enterprises—has received much attention in the database and AI communities. The focus has been on building data integration systems that provide a uniform query interface to the sources. A key bottleneck in building such systems has been the laborious manual construction of semantic mappings between the query interface and the source schemas. Examples of mappings are element location maps to address and price maps to listed-price. We propose a multistrategy learning approach to automatically find such mappings. The approach applies multiple learner modules, where each module exploits a different type of information either in the schemas of the sources or in their data, then combines the predictions of the modules using a meta-learner. Learner modules employ a variety of techniques, ranging from Naive Bayes and nearest-neighbor classification to entity recognition and information retrieval. We describe the LSD system, which employs this approach to find semantic mappings. To further improve matching accuracy, LSD exploits domain integrity constraints, user feedback, and nested structures in XML data. We test LSD experimentally on several real-world domains. The experiments validate the utility of multistrategy learning for data integration and show that LSD proposes semantic mappings with a high degree of accuracy. 相似文献
99.
María Jose García-Jimnez Myriam Torres-Rico Jos L. de Paz Pedro M. Nieto 《International journal of molecular sciences》2022,23(6)
Pleiotrophin (PTN) is a neurotrophic factor that participates in the development of the embryonic central nervous system (CNS) and neural stem cell regulation by means of an interaction with sulfated glycosaminoglycans (GAGs). Chondroitin sulfate (CS) is the natural ligand in the CNS. We have previously studied the complexes between the tetrasaccharides used here and MK (Midkine) by ligand-observed NMR techniques. The present work describes the interactions between a tetrasaccharide library of synthetic models of CS-types and mimetics thereof with PTN using the same NMR transient techniques. We have concluded that: (1) global ligand structures do not change upon binding, (2) the introduction of lipophilic substituents in the structure of the ligand improves the strength of binding, (3) binding is weaker than for MK, (4) STD-NMR results are compatible with multiple binding modes, and (5) the replacement of GlcA for IdoA is not relevant for binding. Then we can conclude that the binding of CS derivatives to PTN and MK are similar and compatible with multiple binding modes of the same basic conformation. 相似文献
100.
Carolina Gismene Jorge Enrique Hernndez Gonzlez Angela Rocio Nio Santisteban Andrey Fabricio Ziem Nascimento Lucas dos Santos Cunha Fbio Rogrio de Moraes Cristiano Luis Pinto de Oliveira Caio C. Oliveira Paola Jocelan Scarin Provazzi Pedro Geraldo Pascutti Raghuvir Krishnaswamy Arni Ricardo Barros Mariutti 《International journal of molecular sciences》2022,23(17)
Staphylococcal exfoliative toxins (ETs) are glutamyl endopeptidases that specifically cleave the Glu381-Gly382 bond in the ectodomains of desmoglein 1 (Dsg1) via complex action mechanisms. To date, four ETs have been identified in different Staphylococcus aureus strains and ETE is the most recently characterized. The unusual properties of ETs have been attributed to a unique structural feature, i.e., the 180° flip of the carbonyl oxygen (O) of the nonconserved residue 192/186 (ETA/ETE numbering), not conducive to the oxyanion hole formation. We report the crystal structure of ETE determined at 1.61 Å resolution, in which P186(O) adopts two conformations displaying a 180° rotation. This finding, together with free energy calculations, supports the existence of a dynamic transition between the conformations under the tested conditions. Moreover, enzymatic assays showed no significant differences in the esterolytic efficiency of ETE and ETE/P186G, a mutant predicted to possess a functional oxyanion hole, thus downplaying the influence of the flip on the activity. Finally, we observed the formation of ETE homodimers in solution and the predicted homodimeric structure revealed the participation of a characteristic nonconserved loop in the interface and the partial occlusion of the protein active site, suggesting that monomerization is required for enzymatic activity. 相似文献