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1.
Gels ; 8(1)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35049575

RESUMO

With the currently available materials and technologies it is difficult to mimic the mechanical properties of soft living tissues. Additionally, another significant problem is the lack of information about the mechanical properties of these tissues. Alternatively, the use of phantoms offers a promising solution to simulate biological bodies. For this reason, to advance in the state-of-the-art a wide range of organs (e.g., liver, heart, kidney as well as brain) and hydrogels (e.g., agarose, polyvinyl alcohol -PVA-, Phytagel -PHY- and methacrylate gelatine -GelMA-) were tested regarding their mechanical properties. For that, viscoelastic behavior, hardness, as well as a non-linear elastic mechanical response were measured. It was seen that there was a significant difference among the results for the different mentioned soft tissues. Some of them appear to be more elastic than viscous as well as being softer or harder. With all this information in mind, a correlation between the mechanical properties of the organs and the different materials was performed. The next conclusions were drawn: (1) to mimic the liver, the best material is 1% wt agarose; (2) to mimic the heart, the best material is 2% wt agarose; (3) to mimic the kidney, the best material is 4% wt GelMA; and (4) to mimic the brain, the best materials are 4% wt GelMA and 1% wt agarose. Neither PVA nor PHY was selected to mimic any of the studied tissues.

2.
Animals (Basel) ; 11(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34438639

RESUMO

The physiological and endocrine benefits of sustained exercise in fish were largely demonstrated, and this work examines how the swimming activity can modify the effects of two diets (high-protein, HP: 54% proteins, 15% lipids; high-energy, HE: 50% proteins, 20% lipids) on different growth performance markers in gilthead sea bream juveniles. After 6 weeks of experimentation, fish under voluntary swimming and fed with HP showed significantly higher circulating growth hormone (GH) levels and plasma GH/insulin-like growth-1 (IGF-1) ratio than fish fed with HE, but under exercise, differences disappeared. The transcriptional profile of the GH-IGFs axis molecules and myogenic regulatory factors in liver and muscle was barely affected by diet and swimming conditions. Under voluntary swimming, fish fed with HE showed significantly increased mRNA levels of capn1, capn2, capn3, capns1a, n3, and ub, decreased gene and protein expression of Ctsl and Mafbx and lower muscle texture than fish fed with HP. When fish were exposed to sustained exercise, diet-induced differences in proteases' expression and muscle texture almost disappeared. Overall, these results suggest that exercise might be a useful tool to minimize nutrient imbalances and that proteolytic genes could be good markers of the culture conditions and dietary treatments in fish.

3.
Front Plant Sci ; 11: 560024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33224158

RESUMO

Four rotation sequences consisting of ungrafted tomato cv. Durinta - melon cv. Paloma or tomato grafted onto the resistant rootstock 'Aligator' - melon grafted onto the resistant Cucumis metuliferus accession BGV11135, and in reverse order, were conducted from 2015 to 2017 in a plastic greenhouse infested or not with Meloidogyne incognita to determine the plant tolerance (T), the minimum relative crop yield (m) and fruit quality. The relationship between M. incognita densities in soil at transplanting (Pi) of each crop and the crop yield was assessed and T and m were estimated by the Seinhorst's damage model. In addition, the volume and the number of nuclei of single giant cells and the number of giant cells, its volume and the number of nuclei per feeding site in susceptible tomato and melon were compared to those in the resistant tomato and C. metuliferus 15 days after nematode inoculation in pot test. The relationship between the Pi and the relative crop yield fitted the Seinhorst's damage model in both ungrafted and grafted tomato and melon, but not for all years and cropping seasons. The estimated T for ungrafted and grafted tomato did not differ but m was lower in the former (34%) than the latter (67%). Sodium concentration in fruits from ungrafted but not from grafted tomato increased with nematode densities in spring 2015 and 2016. The estimated ungrafted melon T did not differ from the grafted melon cultivated in spring, but it did when it was cultivated in summer. The relative crop yield of ungrafted melon was lower (2%) than the grafted cultivated in spring (62%) and summer (20%). Sodium concentration in melon fruits from ungrafted plants increased with nematode densities. No variations in fruit quality from grafted melon cultivated in spring were found, although less dry matter and soluble solid content at highest nematode densities were registered when it was cultivated in summer. Lower number of giant cells per feeding site was observed in both susceptible tomato germplasms compared to the resistant ones but they were more voluminous and held higher number of nuclei per giant cell and per feeding site.

4.
J Sci Food Agric ; 96(2): 413-21, 2016 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25615522

RESUMO

BACKGROUND: The commercial potato cultivars are diverse not only in their physical characteristics but also in their nutritional compositions and their content of functional compounds (resistant starch, total phenolic content and antioxidant activity), but there is little information about these differences. The aim of this study was to characterise the nutritional value (focusing on carbohydrates and functional compounds) and instrumental parameters of eight potato cultivars consumed in Spain and to determine whether these parameters are useful for classifying the cultivars. RESULTS: Significant Pearson's correlations were found due to the common and complex interactions between the constituents of potatoes and their properties (P < 0.05). Principal component analysis revealed the correlations among the physicochemical properties, and the first two principal components explained 56.84% of the variance among the cultivars studied. CONCLUSION: The eight cultivars could be classified into three groups: (1) Red Pontiac, Caesar, Kennebec, Agria and Cherie cultivars, (2) Agata and Monalisa cultivars and (3) Spirit cultivar. The results demonstrated that certain nutritional and functional parameters indicated the potential efficacy of different cultivars to satisfy the nutritional needs of consumers, improving the knowledge on the biochemical basis of potato processing to obtain higher-quality products.


Assuntos
Manipulação de Alimentos , Tubérculos/química , Tubérculos/classificação , Solanum tuberosum/classificação , Antioxidantes , Carboidratos/química , Concentração de Íons de Hidrogênio , Fenóis , Pigmentação , Análise de Componente Principal
5.
Food Chem ; 197 Pt B: 1301-10, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26675872

RESUMO

The different intensities of common culinary techniques (boiling, baking and microwaving) produce several changes that reduce the nutritional and physical properties of potatoes. This study evaluated the effect of those cooking methods on the quality of commercial potato tubers (Agata, Kennebec, Caesar and Red Pontiac). The higher weight losses were obtained for baking, but the potato softening depended on the cultivar. Color losses were independent of the intensity of the treatment; however, microwaving promoted a prompt starch gelatinization with respect to the other methods. The resistant starch retention of baking and microwaving was higher than that of boiling, and the maximum retention of bioactive compounds was obtained with the lower core temperature during boiling, as well as higher temperature and shorter baking time and the lower power and longer microwaving time. Principal component analysis revealed significant relationships between the instrumental and functional properties of cooked potatoes.


Assuntos
Culinária/métodos , Solanum tuberosum/química , Antioxidantes/farmacologia , Carboidratos/análise , Cor , Temperatura Alta , Fenóis/análise , Tubérculos/química , Análise de Componente Principal , Amido/química
6.
J Agric Food Chem ; 55(13): 5147-55, 2007 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-17536831

RESUMO

Osmotic dehydration was assessed as an operation for supplementing a solid foodstuff (a gel was used as the model food) with grape phenolics from a concentrated red grape must to increase its antioxidant properties. The model food was processed for up to 24 h, and the osmotic pressure was adjusted by diluting the concentrated red grape must. In all conditions tested, low molecular weight phenolics (

Assuntos
Antioxidantes/análise , Alimentos Fortificados/análise , Frutas/química , Fenóis/administração & dosagem , Fenóis/análise , Vitis/química , Flavonoides/administração & dosagem , Flavonoides/análise , Conservação de Alimentos , Polifenóis
7.
J Agric Food Chem ; 54(26): 9955-8, 2006 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-17177527

RESUMO

A semi-industrial application of the continuous stabilization of white wine protein using a column packed with zirconia was studied and compared to the traditional bentonite treatment using a Macabeu white wine. Physicochemical and wine sensory properties were evaluated using a rating system and triangle tests. Continuous protein stabilization was analyzed in three residence times, and the equivalent of 300 BV of wine was used for both treatments. Wine protein content was reduced by 21%, 40%, and 42% using the continuous process with residence times of 7.5, 15, and 30 min, respectively, and by 61.4% using the bentonite treatment. The wines obtained from the packed column were protein stable up to 25, 75, and 175 BV for residence times of 7.5, 15, and 30 min, respectively. The amount of polyphenol removed was less than 10%, and similar amounts were removed from the wine regardless of residence time, while 20.6% of polyphenol was removed using bentonite. The physicochemical and sensory properties of wine treated with bentonite were similar to those of wine treated with zirconia.


Assuntos
Bentonita , Proteínas de Plantas/análise , Sensação , Vinho/análise , Zircônio , Adsorção , Bentonita/química , Fenômenos Químicos , Físico-Química , Flavonoides/análise , Manipulação de Alimentos/métodos , Fenóis/análise , Polifenóis , Zircônio/química
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