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91.
Renê O. Couto Edemilson C. ConceiçãoLuíza T. Chaul Ezequiane M.S. OliveiraFrederico S. Martins Maria Teresa F. BaraKênnia R. Rezende Suzana F. AlvesJosé R. Paula 《Food chemistry》2012,131(1):99-105
In this work, spray-dried rosemary extracts were obtained. A 33 Box-Behnken design was followed to evaluate the influence of drying conditions on the contents of chemical markers and “in vitro” antioxidant activity of the powder. Although the dry products lost some of their polyphenols, they still had antioxidant activities (IC50) ranging from 17.6 to 24.8 μg · mL−1. Analysis of variance proved that studied factors and some of their interactions significantly affected most of the quality indicators. The best combination of conditions to use for obtaining dry rosemary extracts with adequate physicochemical and functional properties involves an extract feed rate of 6 mL · min−1, a drying air inlet temperature of 140 °C and a spray nozzle air flow rate of 50 L · min−1. 相似文献
92.
Fernanda Montenegro Barbosa Camila Valdejane Silva de Souza Ellane Sabryna Ribeiro Paulo Roberto Medeiros de Azevedo Karla Suzanne Florentino da Silva Chaves Damasceno Larissa Mont'Alverne Juc Seabra 《Journal of Food Safety》2021,41(1):e12869
The aim of the study was to evaluate the overall hygienic–sanitary conditions of university hospitals foodservices and assess food safety knowledge and self‐reported practices of food handlers. A self‐administered questionnaire based on sanitary standards for foodservices was given to 123 food handlers from three public hospitals. Microbiological analysis of food handling surfaces and food hygiene inspections were also performed. Food handlers' self‐reported knowledge and practices reached satisfactory levels (77.2% and 78.1%, respectively), and showed a significant positive intercorrelation (p < .05). Food hygiene inspections in the hospitals foodservices presented a 60.9% average of adequacy and microbiological analysis results showed that 66.7% of the evaluated surfaces presented significant contamination by mesophilic bacteria. The presence of coliforms at 45°C above the safety limit was identified in 47.9% of the surfaces. The results showed a need for motivating hospital food handlers to practice the safe handling knowledge that they have demonstrated in theory. 相似文献
93.
94.
Flavia Aparecida Reitz Cardoso Regiani Aparecida de Almeida Ricardo Vicente de Paula Rezende LucioCardozo-Filho Dirceu Norile Henry Franga Meier Vladimir Ferreira Cabral 《化学与化工:英文版》2014,(4):408-416
To investigate the influence of pressure and temperature on the jet velocity of a three-dimensional flow was the main goal of this study. Using a precipitation chamber with approximate capacity of 600 mL, it was studied the thermodynamic behavior of supercritical carbon dioxide mixture, dichloromethane and grape seed extract via SAS (supercritical antisolvent process). For the numerical solution, the Navier-Stokes equations were used along with the model of turbulence k-ε and Peng-Robinson equation of state with quadratic mixing rules of Van der Waals. The method of Chung was employed to determine the viscosity, thermal conductivity and mass diffusivity of the flow numerically solved through commercial code based on CFD (computational fluid dynamics). Simulations for pressures between 80 bar and 160 bar and temperatures between 308.15 K and 318.15 K showed large variations in the jet velocity, an important property in the dynamic mixing process that involves the size, size distribution and particle morphology. 相似文献
95.
96.
Thatyane Vidal Fonteles Mayra Garcia Maia Costa Ana Laura Tibério de Jesus Cláudia Patrícia Mourão Lima Fontes Fabiano André Narciso Fernandes Sueli Rodrigues 《Food and Bioprocess Technology》2013,6(10):2860-2869
The use of sonicated melon juice as substrate for Lactobacillus casei growth in cantaloupe melon juice and its effect on product quality were investigated. The survival of L. casei in the fermented juice, the product color, the post-acidification and other quality parameters were evaluated in the refrigerated product (4 °C) for a period of 42 days. Storage pH, color, sugar content, lactic acid concentration, biomass and viable cells count were determined. The caloric value of the product was also evaluated. During the refrigerated storage period, acidification and a slight reduction in the number of viable cells were observed. However, a sufficient number of viable cells were observed to guarantee the beneficial properties from probiotic consumption (>8 log CFU?ml?1) throughout the storage period, for both stocked samples (with and without sugar addition). The product color was also preserved during storage. The developed product resulted in a low caloric product. The caloric value was reduced during the storage period due to sugar consumption by the remaining microorganisms. 相似文献
97.
Michelle Leali Costa Mirabel Cerqueira Rezende Jane Maria Faulstich de Paiva Edson Cocchieri Botelho 《Polymer-Plastics Technology and Engineering》2013,52(10):1143-1153
Two different carbon/epoxy prepreg materials were characterized and compared using thermal (DSC, TGA, and DMA) and rheological analyses. A prepreg system (carbon fiber preimpregnated with epoxy resin F584) that is currently used in the commercial airplane industry was compared with a prepreg system that is a prospective candidate for the same applications (carbon fiber prepreg/epoxy resin 8552). The differences in the curing kinetics mechanisms of both prepreg systems were identified through the DSC, TGA, DMA, and rheological analyses. Based on these thermal analysis techniques, it was verified that the curing of both epoxy resin systems follow a cure kinetic of n order. Even though their reaction heats were found to be slightly different, the kinetics of these systems were nevertheless very similar. The activation energies for both prepreg systems were determined by DSC analysis, using Arrhenius's method, and were found to be quite similar. DMA measurements of the cured prepregs demonstrated that they exhibited similar degrees of cure and different glass transition temperatures. Furthermore, the use of the rheological analysis revealed small differences in the gel temperatures of the two prepreg systems that were examined. 相似文献
98.
Mayra Colardo Michele Petraroia Letizia Lerza Daniele Pensabene Noemi Martella Valentina Pallottini Marco Segatto 《International journal of molecular sciences》2022,23(9)
Cholesterol plays a crucial role in the brain, where its metabolism is particularly regulated by astrocytic activity. Indeed, adult neurons suppress their own cholesterol biosynthesis and import this sterol through ApoE-rich particles secreted from astrocytes. Recent evidence suggests that nerve growth factor (NGF) may exert neurotrophic activity by influencing cell metabolism. Nevertheless, the effect of NGF on glial cholesterol homeostasis has still not been elucidated. Thus, the aim of this project is to assess whether NGF could influence cholesterol metabolism in glial cells. To reach this objective, the U373 astrocyte-derived cell line was used as an experimental model. Immunoblot and ELISA analysis showed that proteins and enzymes belonging to the cholesterol metabolism network were increased upon NGF treatment in glial cells. Furthermore, NGF significantly increased ApoE secretion and the amount of extracellular cholesterol in the culture medium. Co-culture and U373-conditioned medium experiments demonstrated that NGF treatment efficiently counteracted rotenone-mediated cytotoxicity in N1E-115 neuronal cells. Conversely, neuroprotection mediated by NGF treatment was suppressed when N1E-115 were co-cultured with ApoE-silenced U373 cells. Taken together, these data suggest that NGF controls cholesterol homeostasis in glial cells. More importantly, NGF exerts neuroprotection against oxidative stress, which is likely associated with the induction of glial ApoE secretion. 相似文献
99.
Mayra A. Mendez-Encinas Elizabeth Carvajal-Millan Madhav P. Yadav Yolanda L. López-Franco Agustín Rascon-Chu Jaime Lizardi-Mendoza Francisco Brown-Bojorquez Erika Silva-Campa Martín Pedroza-Montero 《应用聚合物科学杂志》2019,136(15):47300
Arabinoxylans (AX) treated with protease and dialyzed (AXP) or only dialyzed (AXD) formed gels showing an increase in the elastic modulus G′ (1291 and 1419 Pa, respectively) and the ferulic acid dimers (3.34 and 3.10 μg/mg polysaccharide, respectively) and trimers (0.51 and 0.53 μg/mg polysaccharide, respectively) in comparison to AX gels (767 Pa, 0.56 and 0.12 μg/mg polysaccharide, respectively). Nevertheless, the G′ values and crosslinking contents were not different among the AXP and AXD gels, suggesting that the amount of protein removed (54%) does not affect these parameters. Confocal laser scanning microscopy analysis showed that AXP treatment promotes the homogeneity of the gels. In addition, scanning electron microscopy observations indicated that AXD and particularly AXP gels had a more compact microstructure. Thus, the partial removal of protein associated with AX does not impact the viscoelasticity and crosslinking content of the gels formed but could improve their microstructural characteristics. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47300. 相似文献
100.
Diana Jhoseline Medina-Leyte Oscar Zepeda-García Mayra Domínguez-Prez Antonia Gonzlez-Garrido Teresa Villarreal-Molina Leonor Jacobo-Albavera 《International journal of molecular sciences》2021,22(8)
Coronary artery disease (CAD) and its complications are the leading cause of death worldwide. Inflammatory activation and dysfunction of the endothelium are key events in the development and pathophysiology of atherosclerosis and are associated with an elevated risk of cardiovascular events. There is great interest to further understand the pathophysiologic mechanisms underlying endothelial dysfunction and atherosclerosis progression, and to identify novel biomarkers and therapeutic strategies to prevent endothelial dysfunction, atherosclerosis and to reduce the risk of developing CAD and its complications. The use of liquid biopsies and new molecular biology techniques have allowed the identification of a growing list of molecular and cellular markers of endothelial dysfunction, which have provided insight on the molecular basis of atherosclerosis and are potential biomarkers and therapeutic targets for the prevention and or treatment of atherosclerosis and CAD. This review describes recent information on normal vascular endothelium function, as well as traditional and novel potential biomarkers of endothelial dysfunction and inflammation, and pharmacological and non-pharmacological therapeutic strategies aimed to protect the endothelium or reverse endothelial damage, as a preventive treatment for CAD and related complications. 相似文献