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71.
Leandro Nole Eduardo Arnaud Bertrand Thierry Frdou Alex Souza Lira Rayssa Siqueira Lima Beatrice Padovani Ferreira Frdric Menard Flvia Lucena‐Frdou 《水产资源保护:海洋与淡水生态系统》2020,30(4):761-774
- Tetraodontiformes fishes play a critical role in benthic and demersal communities and are facing threats due to anthropogenic impacts and climate change. However, they are poorly studied worldwide. To improve knowledge on the socio‐ecological significance and conservation of Tetraodontiformes a review of literature addressing the diversity, ecology, use and trade, conservation, and main threats of Tetraodontiformes combined with a comprehensive in situ dataset from two broad‐range multidisciplinary oceanographic surveys performed along the Tropical Brazilian Continental Shelf was undertaken.
- Twenty‐nine species were identified, being primarily found on coral reefs and algal ecosystems. At these habitats, tetraodontids present highly diversified trophic categories and might play an important role by balancing the marine food web
- Coral reef ecosystems, especially those near to the shelf break, seem to be the most important areas of Tetraodontiformes fishes, concentrating the highest values of species richness, relative abundance and the uncommon and Near Threatened species.
- Ninety per cent of species are commonly caught as bycatch, being also used in the ornamental trade (69%) and as food (52%), serving as an important source of income for artisanal local fisheries.
- Tetraodontiformes are threatened by unregulated fisheries, overexploitation, bycatch, and habitat loss due to coral reef degradation and the potential effects of climate change. These factors are more broadly impacting global biodiversity, food security, and other related ecosystem functions upon which humans and many other organisms rely.
- We recommend the following steps that could improve the conservation of Tetraodontiformes along the tropical Brazilian Continental shelf and elsewhere: (i) data collection of the commercial, incidental, ornamental and recreational catches; (ii) improvement of the current legislation directed at the marine ornamental harvesting; (iii) increase efforts focused on the education and conservation awareness in coastal tourism and communities; and, most important, (iv) creation of marine reserves networks in priority areas of conservation, protecting either the species and key habitats for its survival.
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73.
Cytoprotection by neutral fraction of tannat red wine against oxidative stress-induced cell death 总被引:1,自引:0,他引:1
Echeverry C Blasina F Arredondo F Ferreira M Abin-Carriquiry JA Vasquez L Aspillaga AA Diez MS Leighton F Dajas F 《Journal of agricultural and food chemistry》2004,52(24):7395-7399
Some of the beneficial effects of the Mediterranean diet on human pathologies have been attributed to red wine polyphenols. It has been postulated that the antioxidant activity of the latter would be also responsible for the cytoprotective capacity of red wine that has been reported in a few papers. Nevertheless, red wine shows a complex composition, and the active fraction is not known yet. In this context, the protective capacity of total lyophilized extracts of red wine and anthocyanin, neutral, or acidic fractions, was explored in PC12 cells in culture after a hydrogen peroxide insult. Although all fractions showed high antioxidant activity, only the neutral fraction was cytoprotective. The analysis of this active fraction showed that it was rich in the aglycons quercetin and myricetin as well as the glycosides of kaempferol, isorhamnetin, epicatechin, and catechin, some of which are known to be cytoprotective. This is the first paper to reveal the active fraction of total wine responsible of its cytoprotection. 相似文献
74.
Kamara BI Brandt EV Ferreira D Joubert E 《Journal of agricultural and food chemistry》2003,51(13):3874-3879
The fermented leaves and stems of Cyclopia intermedia are used to brew Honeybush tea, a herbal tea indigenous to South Africa. The plant is also used to manufacture a sweet herbal infusion used for restorative properties such as soothing coughs and alleviating bronchial complaints including tuberculosis, pneumonia, and catarrh. It is claimed to have a low tannin content and no caffeine and contains various antioxidants. Continued investigations into the phenolic content of the leaves and stems of C. intermedia yielded tyrosol and a methoxy analogue, 2-[4-[O-alpha-apiofuranosyl-(1' '-->6')-beta-d-glucopyranosyloxy]phenyl]ethanol, 4-[O-alpha-apiofuranosyl-(1' '-->2')-beta-d-glucopyranosyloxy]benzaldehyde, five glycosylated flavonols, two isoflavones, four flavanones, two isoflavones, and two flavones. Structure elucidation was done by NMR, CD, and MS methods. Because flavonoids are presumed to contribute significantly toward the scavenging effects of active oxygen species, our results indicate that the tentative claimed health-promoting properties may be attributed to the presence of these and other phenolics in C. intermedia. 相似文献
75.
Oliveira CM Silva Ferreira AC Guedes De Pinho P Hogg TA 《Journal of agricultural and food chemistry》2002,50(7):2121-2124
This work describes a new potentiometric method to evaluate the resistance to oxidation of white wines. Reduction and oxidation titrations were made, and coefficient of variation obtained were 10.87 and 2.65%, respectively. The antioxidant powers of ascorbic acid (Aas) and sulfur dioxide (SO(2)) were evaluated by this method, SO(2) proving to be much less active in this respect than ascorbic acid. The two agents did not demonstrate any antioxidant synergy. A relationship between oxygen present and ascorbic acid was found by the proposed method (1 mmol of O(2) <--> 0.84 mmol of Aas). This method enables the distinction of different wines on the basis of their resistance to oxidation. 相似文献
76.
Effect of coupling media on velocity and attenuation of ultrasonic waves in Brazilian wood 总被引:1,自引:0,他引:1
Raquel?Gon?alvesEmail author Alex?Julio?Trinca Gisleiva?Cristina?dos?Santos Ferreira 《Journal of Wood Science》2011,57(4):282-287
Coupling media are necessary to ensure that transducers bond to wood specimens to minimize coupling losses and improve the
accuracy of ultrasonic measurements. There are several types of coupling media available, and the optimal choice is not known.
In this work, we analyzed the results of ultrasonic wave attenuation for 0.1-MHz longitudinal and transverse transducers with
six different materials as coupling media in nine species of Brazilian wood with densities in the range 700–1170 kg/m3. Tests were performed using constant pressure on the transducer and with wave propagation in the longitudinal direction.
For transverse transducers, the polarization was in the radial and tangential directions. The results were analyzed statistically
and showed that, for attenuation in both longitudinal and transverse waves, the material used for coupling had significant
effects, whereas the wood species had no effect. For longitudinal waves, the statistical evaluation showed that the coupling
material performance was strongly dependent on the species of wood, but it was not possible to observe any tendency of behavior
associated with specific anatomical properties. 相似文献
77.
Ferreira V Ortín N Escudero A López R Cacho J 《Journal of agricultural and food chemistry》2002,50(14):4048-4054
The aroma of a Grenache rosé wine from Calatayud (Zaragoza, Spain) has been elucidated following a strategy consisting of an aroma extract dilution analysis (AEDA), followed by the quantitative analysis of the main odorants and the determination of odor activities values (OAVs) and, finally, by a series of reconstitution and omission tests with synthetic aroma models. Thirty-eight aroma compounds were found in the AEDA study, 35 of which were identified. Twenty-one compounds were at concentrations higher than their corresponding odor thresholds. An aroma model prepared by mixing the 24 compounds with OAV > 0.5 in a synthetic wine showed a high qualitative similarity with the aroma of the rosé wine. The addition of compounds with OAV < 0.5 did not improve the model, whereas the aroma of a model containing only odorants with OAV > 10 was very different from that of the wine. Omission tests revealed that the most important odorant of this Grenache rosé wine was 3-mercapto-1-hexanol, with a deep impact on the wine fruity and citric notes. The synergic action of Furaneol and homofuraneol also had an important impact on wine aroma, particularly in its fruity and caramel notes. The omission of beta-damascenone, which had the second highest OAV, caused only a slight decrease on the intensity of the aroma model. Still weaker was the sensory effect caused by the omission of 10 other compounds, such as fatty acids and their ethyl esters, isoamyl acetate, and higher alcohols. 相似文献
78.
Zhu Y Murali S Stoller MD Ganesh KJ Cai W Ferreira PJ Pirkle A Wallace RM Cychosz KA Thommes M Su D Stach EA Ruoff RS 《Science (New York, N.Y.)》2011,332(6037):1537-1541
Supercapacitors, also called ultracapacitors or electrochemical capacitors, store electrical charge on high-surface-area conducting materials. Their widespread use is limited by their low energy storage density and relatively high effective series resistance. Using chemical activation of exfoliated graphite oxide, we synthesized a porous carbon with a Brunauer-Emmett-Teller surface area of up to 3100 square meters per gram, a high electrical conductivity, and a low oxygen and hydrogen content. This sp(2)-bonded carbon has a continuous three-dimensional network of highly curved, atom-thick walls that form primarily 0.6- to 5-nanometer-width pores. Two-electrode supercapacitor cells constructed with this carbon yielded high values of gravimetric capacitance and energy density with organic and ionic liquid electrolytes. The processes used to make this carbon are readily scalable to industrial levels. 相似文献
79.
Barata A Campo E Malfeito-Ferreira M Loureiro V Cacho J Ferreira V 《Journal of agricultural and food chemistry》2011,59(6):2543-2553
In the present work, the aroma profiles of wines elaborated from sound and sour rot-infected grapes as raw material have been studied by sensory analysis, gas chromatography-olfactometry (GC-O), and gas chromatography-mass spectrometry (GC-MS), with the aim of determining the odor volatiles most likely associated with this disease. The effect of sour rot was tested in monovarietal wines produced with the Portuguese red grape variety Trincadeira and in blends of Cabernet Sauvignon and sour rotten Trincadeira grapes. Wines produced from damaged berries exhibited clear honey-like notes not evoked by healthy samples. Ethyl phenylacetate (EPhA) and phenylacetic acid (PAA), both exhibiting sweet honey-like aromas, emerged as key aroma compounds of sour rotten wines. Their levels were 1 order of magnitude above those found in controls and reached 304 and 1668 μg L(-1) of EPhA and PAA, respectively, well above the corresponding odor thresholds. Levels of γ-nonalactone also increased by a factor 3 in sour rot samples. Results also suggest that sour rot exerts a great effect on the secondary metabolism of yeast, decreasing the levels of volatiles related to fatty acids and amino acid synthesis. The highest levels of γ-decalactone of up to 405 μg L(-1) were also found in all of the samples, suggesting that this could be a relevant aroma compound in Trincadeira wine aroma. 相似文献
80.