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91.
Fl��via Santos Twardowski Pinto Simone Hickmann Fl?res Carolina Elisa Schneider Marco Antonio Z��chia Ayub Plinho Francisco Hertz 《Food and Bioprocess Technology》2011,4(4):559-565
In this work, the influence of oxygen mass transfer rates on the production of cyclodextrin glycosyltransferase (CGTase) by
the alkaliphilic bacterium Bacillus circulans ATCC 21783 was investigated. Experimental design and response surface methodology were applied to optimize agitation speed
and air flow rate in batch cultivations, in order to identify their significant effects and interactions with the synthesis
of CGTase. Results were expressed as the volumetric mass transfer rates of oxygen (kla, [per hour]). The maximal CGTase productivity of 155 U mL−1 h−1 was achieved with kla of 48 h−1. CGTase production was also studied in fed-batch cultures using the optimized parameters obtained in the batch experiments.
The maximal CGTase productivity on fed-batch cultivations was 137 U mL−1 h−1 with feeding rates of starch at 0.17 g L−1 h−1. 相似文献
92.
Salgado Ana Carolina Duarte Otto Carlos Muniz Bandeira 《Multimedia Tools and Applications》1999,8(3):289-291
Multimedia Tools and Applications - 相似文献
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Cristiane Franco Codevilla Tamara dos Santos Castilhos Carolina Araújo Cirne Pedro Eduardo Froehlich Ana Maria Bergold 《Drug development and industrial pharmacy》2014,40(4):488-493
Introduction: Lodenafil carbonate is a phosphodiesterase type 5 inhibitor used for the treatment of erectile dysfunction. Currently, there is no dissolution test reported for lodenafil carbonate and this drug is not listed in any pharmacopoeia.Objective: The present study focused on the development and validation of a dissolution test for lodenafil carbonate tablets, using a simulated absorption profile based on in vivo data.Methods: The appropriate conditions were determined after testing sink conditions. Different conditions as medium, surfactant concentration and rotation speed were evaluated. The percentage of dose absorbed was calculated by deconvolution, using the Wagner–Nelson method.Results: According to the obtained results, the use of 0.1?M HCl?+?1.5% SLS (900?mL, at 37?+?0.5?°C) as the dissolution medium, paddles at 25?rpm were considered adequate. The samples were quantified by UV spectroscopy at 295?nm and the validation was performed according to international guidelines. The method showed specificity, linearity, accuracy and precision, within the acceptable range. Kinetics of drug release was better described by the first-order model.Conclusion: The proposed dissolution test can be used for the routine quality control of lodenafil carbonate in tablets. 相似文献
96.
Jemish Parmar Xing Ma Jaideep Katuri Juliane Simmchen Morgan M Stanton Carolina Trichet-Paredes Lluís Soler Samuel Sanchez 《Science and Technology of Advanced Materials》2015,16(1)
Self-propelled micromotors are emerging as important tools that help us understand the fundamentals of motion at the microscale and the nanoscale. Development of the motors for various biomedical and environmental applications is being pursued. Multiple fabrication methods can be used to construct the geometries of different sizes of motors. Here, we present an overview of appropriate methods of fabrication according to both size and shape requirements and the concept of guiding the catalytic motors within the confines of wall. Micromotors have also been incorporated with biological systems for a new type of fabrication method for bioinspired hybrid motors using three-dimensional (3D) printing technology. The 3D printed hybrid and bioinspired motors can be propelled by using ultrasound or live cells, offering a more biocompatible approach when compared to traditional catalytic motors. 相似文献
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Jessica Maiuolo Francesca Oppedisano Cristina Carresi Micaela Gliozzi Vincenzo Musolino Roberta Macrì Federica Scarano Annarita Coppoletta Antonio Cardamone Francesca Bosco Rocco Mollace Carolina Muscoli Ernesto Palma Vincenzo Mollace 《International journal of molecular sciences》2022,23(24)
Reduced bioavailability of the nitric oxide (NO) signaling molecule has been associated with the onset of cardiovascular disease. One of the better-known and effective therapies for cardiovascular disorders is the use of organic nitrates, such as glyceryl trinitrate (GTN), which increases the concentration of NO. Unfortunately, chronic use of this therapy can induce a phenomenon known as “nitrate tolerance”, which is defined as the loss of hemodynamic effects and a reduction in therapeutic effects. As such, a higher dosage of GTN is required in order to achieve the same vasodilatory and antiplatelet effects. Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is a cardioprotective enzyme that catalyzes the bio-activation of GTN to NO. Nitrate tolerance is accompanied by an increase in oxidative stress, endothelial dysfunction, and sympathetic activation, as well as a loss of the catalytic activity of ALDH2 itself. On the basis of current knowledge, nitrate intake in the diet would guarantee a concentration of NO such as to avoid (or at least reduce) treatment with GTN and the consequent onset of nitrate tolerance in the course of cardiovascular diseases, so as not to make necessary the increase in GTN concentrations and the possible inhibition/alteration of ALDH2, which aggravates the problem of a positive feedback mechanism. Therefore, the purpose of this review is to summarize data relating to the introduction into the diet of some natural products that could assist pharmacological therapy in order to provide the NO necessary to reduce the intake of GTN and the phenomenon of nitrate tolerance and to ensure the correct catalytic activity of ALDH2. 相似文献
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The use of bovine rumen protein (raw and extruded) as a replacement for extruded soy protein concentrate in three meat products (pork sausage, chicken hamburger, and kibbe) was investigated. Similarity between rumen and soy protein meat products was assessed using triangle tests and sensory acceptability evaluated by consumer panelists using a nine-point hedonic scale. The addition of raw rumen protein was detected in all meat product types tested, while extruded rumen protein was only detected in kibbe. The addition of raw rumen protein decreased the acceptability of pork sausage aroma and flavor, but improved kibbe appearance, texture and overall acceptability. The addition of extruded rumen protein reduced the acceptability of chicken hamburger texture, but improved pork sausage flavor. Replacement of soy protein by bovine rumen protein is feasible based upon sensory results, but depended upon its form and the type of meat product to which it was added. 相似文献
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