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排序方式: 共有524条查询结果,搜索用时 46 毫秒
71.
72.
Carolina Castro Amalia Peréz-Jiménez Filipe Coutinho Geneviève Corraze Stéphane Panserat Helena Peres Aires Oliva Teles Paula Enes 《Fish physiology and biochemistry》2018,44(3):911-918
The aim of the present study was to assess the impact of an acute handling stress on hepatic oxidative status of European sea bass (Dicentrarchus labrax) juveniles fed diets differing in lipid so urce and carbohydrate content. For that purpose, four diets were formulated with fish oil (FO) and vegetable oils (VO) as lipid source and with 20 or 0% gelatinized starch as carbohydrate source. Triplicate groups of fish with 74 g were fed each diet during 13 weeks and then subjected to an acute handling stress. Stress exposure decreased hematocrit (Ht) and hemoglobin (Hb) levels. Independent of dietary treatment, stress exposure increased hepatic lipid peroxidation (LPO). Stressed fish exhibited lower glucose 6-phosphate dehydrogenase (G6PD), catalase (CAT), and superoxide dismutase (SOD) activities, independent of previous nutritional history. In the VO groups, stress exposure increased glutathione peroxidase (GPX) activity. Diet composition had no effect on Ht and Hb levels. In contrast, dietary carbohydrate decreased hepatic LPO and CAT activity and increased glutathione reductase (GR) and G6PD activities. Dietary lipids had no effect on LPO. Fish fed the VO diets exhibited higher G6PD activity than fish fed the FO diets. In conclusion, dietary carbohydrates contributed to the reduction of oxidative stress in fish. However, under the imposed handling stress conditions, liver enzymatic antioxidant mechanisms were not enhanced, which may explain the overall increased oxidative stress. 相似文献
73.
Carine de Freitas Souza Matheus Dellaméa Baldissera Adriane Erbice Bianchini Elisia Gomes da Silva Rosa Helena Veraz Mourão Lenise Vargas Flores da Silva Denise Schmidt Berta Maria Heinzmann Bernardo Baldisserotto 《Fish physiology and biochemistry》2018,44(1):21-34
The viability using Lippia alba essential oil as an anesthetic for fish was studied, particularly with respect to physiological effects during recovery. Anesthesia of silver catfish (Rhamdia quelen) using 100 and 300 μL L?1 of two different chemotypes of L. alba essential oil (citral EO-C and linalool EO-L) prevented the increase of plasma cortisol levels caused by handling, but did not avoid alterations in energetic metabolism. Silver catfish did not have increased the levels of thiobarbituric acid reactive species in the kidney and liver during recovery after anesthesia with either EO, avoiding lipid damage. On the other hand, fish anesthetized with EO-C showed higher protein carbonylation levels, superoxide dismutase, catalase, and glutathione S-transferase activities and non-protein thiol group levels in both tissues compared to controls. Our results suggest that both oils show antioxidant capacity, but anesthesia with EO-L does not cause damage to lipids or proteins, only temporary changes, typical of physiological adjustments during recovery from anesthesia. Therefore, EO-L is an effective anesthetic for silver catfish with fewer side effects than EO-C. 相似文献
74.
Lippia alba (Verbenaceae) hydrolate as sedative of tambaqui (Colossoma macropomum) juveniles in simulated transport conditions 下载免费PDF全文
Hugo Napoleão Pereira da Silva Elen Monique de Oliveira Sousa Janna Laely dos Santos Maia Mônica Tatiane Lima Pinheiro Soraia Valeria de Oliveira Coelho Lameirão Rosa Helena Veras Mourão José Guilherme Soares Maia Bernardo Baldisserotto Lenise Vargas Flores da Silva 《Aquaculture Research》2018,49(1):128-134
Lippia alba hydrolate (LAH) is produced as a secondary product in essential oil extraction. The objective of this study was to evaluate the use of LAH in a simulation of the transport of tambaqui (Colossoma macropomum) juveniles. A series of 17 hr simulations were performed using load densities of 30, 60 and 90 juveniles per L and four LAH concentrations of 0.4%, 1%, 2% and 5%, with a control of just water. Fish survival, temperature, dissolved oxygen, conductivity, pH, ammonia excretion, alkalinity water hardness and net Na+, K+, Cl‐ fluxes, were all evaluated before and after the transport simulations. Mucous cell densities in the gills were also determined microscopically, post simulation. The results showed that addition of 5% LAH achieved better survival during the simulation than the water control. Dissolved oxygen was significantly lower with an increased load density. Also, conductivity, NH4 excretion and net ionic fluxes (K+ and Cl?) were lower with 5% LAH, although mainly where higher load densities were tested. Mucous cell density was lower in LAH concentrations of 2% and 5%, again with higher load densities. In view of these findings, it is suggested that 5% LAH is an effective sedative for use in the transport of tambaqui, mainly with high load densities. This work is the first study of LAH and highlights its potential applications in aquaculture management. 相似文献
75.
Ivana Šola Mirta Stipaničev Valerija Vujčić Božena Mitić Ana Huđek Gordana Rusak 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(3):189-195
Native Crocus taxa are abundant in regions with moderate and dry climate; however, their potential in the food industry has thus far been neglected. The objective of this study was to compare the quantitative and qualitative flavonoid content and antioxidant and cytotoxic activity in organs of several populations of Croatian native taxa and assess their potential for application in the food industry. The dominant flavonoids in the native Crocus taxa were kaempferol and quercetin. Tepals contained similar or higher concentrations of flavonoid-glycosides than other organs. Tepals from Cvv1 and Cvv2 populations contained more flavonoid-glycosides than the commonly used spice saffron (C. sativus stigmas). The FRAP antioxidant activity of Cvv1 and Cvv5 tepals was similar to that of standard Trolox. DPPH inhibition of Cvv1 and Cvv3 tepals was within the range of that recorded for saffron. Cvv1 tepals significantly reduced reactive oxygen species in the broadest concentration range (50–1000 μg/ml), and showed considerable antioxidant activity in the ABTS assay, equal to 82% of standard Trolox antioxidant activity. A significantly higher concentration of kaempferol-rutinoside was recorded in this than in other taxa. The flavonoid showed a very strong or strong correlation with antioxidant assays results, and a negative correlation with cellular reactive oxygen species concentration. We therefore presumed that kaempferol-rutinoside is one of the main antioxidant phenolics in Crocus tepals. None of the tested extracts showed cytotoxicity toward Caco-2 cells. The results revealed that Cvv tepals have potential as a food supplement and are a promising material for further food safety tests. 相似文献
76.
Luciana Linhares de Azevedo Bittencourt Kelly Alencar Silva Valéria Pereira de Sousa Gizele Cardoso Fontes-Sant’Ana Maria Helena Rocha-Leão 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(4):278-286
In the processing of fruits such as blueberry (Vaccinium sp), that has high levels of phenolic acid, the food industry produces tons of organic waste that causes harm to the environment. Encapsulation is a technique used to take advantage of these wastes. Several methods are used to encapsulate substances, among them ionotropic gelation proves to be a simple, precise, efficient and economical method for obtaining particles with encapsulated bioactives. In this manner, the aim of this study was to test sodium alginate as wall material to encapsulate blueberry residue by ionotropic gelation. The microbeads were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD), total phenolic compounds, antioxidant capacity and in vitro dissolution. The results showed that the microbeads had surface invagination; retention of 67.01% of the phenolic compounds after encapsulation and 68.2%, phenolic release 120 min after in vitro dissolution. The results suggest that the tested matrix was suitable for encapsulation. The produced microbeads are promising for applications in food products, once the phenolic compounds present in the blueberry residues were maintained after encapsulation. 相似文献
77.
Bosiljka Šaravanja Krešimir Malarić Tanja Pušić Darko Ujević 《Fibers and Polymers》2016,17(1):136-142
The aim of this research is to investigate shield effect properties of the fabrics with inox yarns included in the construction, which are used for special professional garments and should protect from electromagnetic microwave irradiation. The investigation was done prior to and after the professional care procedures of dry and wet cleaning in ten cleaning cycles. Shield effect measurements were done on the face and on the back of the fabric, weftwise and warpwise, prior to and after the first, third, fifth, seventh and tenth cycles of dry and wet cleaning, at the frequencies from 0.9 to 2.4 GHz. The results obtained indicated that shield effect of the fabric tested was reduced after professional care procedures, especially so after 5 cycles. The investigations also revealed that shield effect could be considerably enhanced if the inox yarns were incorporated into the fabric in the direction of the warp. 相似文献
78.
Helena M. Amaro Fátima Fernandes Patrícia Valent?o Paula B. Andrade I. Sousa-Pinto F. Xavier Malcata A. Catarina Guedes 《Marine drugs》2015,13(10):6453-6471
Microalgae are well known for their biotechnological potential, namely with regard to bioactive lipidic components—especially carotenoids and polyunsaturated fatty acids (PUFA), well-known for therapeutic applications based on their antioxidant capacity. The aim of this work was to evaluate the influence of four distinct food-grade solvents upon extractability of specific lipidic components, and on the antioxidant capacity exhibited against both synthetic (2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+•)) and biological reactive species (O2•− and •NO−). A eukaryotic microalga (Scenedesmus obliquus (M2-1)) and a prokaryotic one (Gloeothece sp.) were used as case studies. Concerning total antioxidant capacity, the hexane:isopropanol (3:2) and acetone extracts of Sc. obliquus (M2-1) were the most effective against DPPH• and ABTS+•, respectively. Gloeothece sp. ethanol extracts were the most interesting scavengers of O2•−, probably due the high content of linolenic acid. On the other hand, acetone and hexane:isopropanol (3:2) extracts were the most interesting ones in •NO− assay. Acetone extract exhibited the best results for the ABTS assay, likely associated to its content of carotenoids, in both microalgae. Otherwise, ethanol stood out in PUFA extraction. Therefore, profiles of lipidic components extracted are critical for evaluating the antioxidant performance—which appears to hinge, in particular, on the balance between carotenoids and PUFAs. 相似文献
79.
80.
Edita Mazurová Klára Hilscherová Tereza Šídlová-Štěpánková Heinz-R. Köhler Rita Triebskorn Dirk Jungmann John P. Giesy 《Journal of Soils and Sediments》2010,10(3):423-433