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Ortega,Viviana Guadalupe; Ramírez,José Alberto; Velázquez,Gonzalo; Tovar,Beatriz; Mata,Miguel; Montalvo,Efigenia. |
The objective of this study was to evaluate the effect of pressurization on the concentration of some antioxidant compounds and the antiradical efficiency during the ripening process of 'Ataulfo' mango. The fruits at physiological maturity stage were pressurized at 15, 30, or 60 MPa for 10 or 20 min. Control fruits were not pressurized. The fruits were stored at 25 °C and changes in the concentration of ascorbic acid, total phenols, total flavonoids, total carotenoids, and antiradical efficiency were evaluated. It was demonstrated that in 'Ataulfo' mango high hydrostatic pressure treatments at 60 and 30 MPa for 20 minutes induced the synthesis of ascorbic acid during storage maybe as a consequence of physiological changes and possible structural... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mangifera indica L; High hydrostatic pressure; Antioxidants. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612013000300027 |
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Zeng, Xiang; Birrien, Jean-louis; Fouquet, Yves; Cherkashov, Georgy; Jebbar, Mohamed; Querellou, Joel; Oger, Philippe; Cambon-bonavita, Marie-anne; Xiao, Xiang; Prieur, Daniel. |
A novel hydrothermal site was discovered in March 2007, on the mid-Atlantic ridge during the cruise 'Serpentine'. At a depth of 4100 m, the site 'Ashadze' is the deepest vent field known so far. Smoker samples were collected with the ROV 'Victor 6000' and processed in the laboratory for the enrichment of anaerobic heterotrophic microorganisms under high-temperature and high-hydrostatic pressure conditions. Strain CH1 was successfully isolated and assigned to the genus Pyrococcus, within the Euryarchaeota lineage within the Archaea domain. This organism grows within a temperature range of 80 to 108 degrees C and a pressure range of 20 to 120 MPa, with optima for 98 degrees C and 52 MPa respectively. Pyrococcus CH1 represents the first obligate piezophilic... |
Tipo: Text |
Palavras-chave: Thermococcales; Extremophile; Deep sea hydrothermal vent; High hydrostatic pressure; Archaea. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6812.pdf |
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Cario, Anais; Mizgier, Alex; Thiel, Axel; Jebbar, Mohamed; Oger, Phil M.. |
Most Thermococcales accumulate di-myo-inositol-phosphate (DIP) as an organic solute as a response to heat stress. We have studied the accumulation of this osmolyte in the high-hydrostatic pressure adapted hyperthermophile Thermococcus barophilus. We found no accumulation of DIP under any of the stress conditions tested, although this archaeon harbors the 3 DIP synthesis genes. Lack of synthesis is due to the lack of expression of TERMP_01135 coding for the second step of DIP synthesis. In contrast to other species, the T. barophilus synthesis operon is interrupted by a four gene locus, in reverse orientation. Restoring an operon like structure at the DIP locus restored DIP synthesis, but did not have an impact on growth characteristics, suggesting that... |
Tipo: Text |
Palavras-chave: High hydrostatic pressure; Heat stress; Di-myo-inositol-phosphate; Thermococcus barophilus. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00270/38113/37216.pdf |
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Oger, Philippe M.; Jebbar, Mohamed. |
The current paper reviews strategies employed by microorganisms from the deep biosphere, especially piezophiles (from the greek piezo = to press and philo = love), to cope with high hydrostatic pressure (HHP) prevailing in these biotopes. The aim of this review is not to constitute an exhaustive report of our current knowledge on the physiology of piezophiles, as recent reviews have covered part of this subject in detail (Abe, 2007; Lauro and Bartlett, 2008; Michiels et al., 2008; Simonato et al., 2006). Rather, we illustrate here, via a few chosen examples, where we stand in our understanding of the mechanisms employed by microorganisms from the depths of our planet to cope with HHP. (C) 2010 Institut Pasteur. Published by Elsevier Masson SAS. All rights... |
Tipo: Text |
Palavras-chave: Adaptation and evolution; Archaea; Deep biosphere; High hydrostatic pressure; Piezophile; Stress response. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00027/13797/11043.pdf |
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