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Your search keyword '"Roulard, Romain"' showing total 9 results
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9 results on '"Roulard, Romain"'

3. Relationship Between the Structure of the Flavone C -Glycosides of Linseed (Linum usitatissimum L.) and Their Antioxidant Activity.

Author

Ghozzi, Imen, Fontaine, Jean-Xavier, Molinié, Roland, Elboutachfaiti, Redouan, Akkouche, Lylia, Sebei, Khaled, Mathiron, David, Hano, Christophe, Garros, Laurine, Choque, Elodie, Roulard, Romain, Petit, Laurent, Delattre, Cédric, Petit, Emmanuel, and Quéro, Anthony

Subjects
FLAX, IRON chelates, FLAVONOIDS, METHYL groups, HYDROXYL group, FLAVONES
Abstract

Flavonoids have been documented to have good antioxidant activities in vitro. In recent years, reports on the antioxidant activities of flavone C-glycosides, a subclass of flavonoids, have attracted great attention. Despite the wealth of information on this subject, the correlation between structure and function is not well understood. In this work, the relationship between the structure and the antioxidant activity of 12 flavone C-glycosides extracted from the aerial part of winter linseed (Linum usitatissimum L.) was studied to fill the current gaps. Orientin, isoorientin, vitexin, isovitexin, swertisin, swertiajaponin, carlinoside, schaftoside, lucenin-1, lucenin-2, vicenin-1, and vicenin-2 were purified by preparative HPLC and by the drowning-out crystallization method. Then, the control of the purity and the confirmation of the chemical structures were assessed by LC-MS and NMR analyses. The antioxidant activity was evaluated using ABTS, CUPRAC, FRAP, and iron chelating activity in vitro assays. Luteolin and its flavone C-glycoside derivatives exhibited higher antioxidant activity than apigenin and its flavone C-glycosides derivatives. This could be attributed to the ortho-dihydroxyl groups at C-3′ and C-4′ of the B ring in the flavonoid skeleton, which seemed to play an important role in antioxidant behavior. These results indicate that the antioxidant activity of these compounds, derived from apigenin and luteolin, can be closely related to their structural characteristics, including the position and nature of the sugars, the number of hydroxyl groups, and the presence of methyl group. [ABSTRACT FROM AUTHOR]

Published
2024
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4. Growth-inhibiting effects of the unconventional plant APYRASE 7 of Arabidopsis thaliana influences the LRX/RALF/FER growth regulatory module

Author

Gupta, Shibu; https://orcid.org/0000-0003-0412-7423, Guérin, Amandine; https://orcid.org/0000-0001-7143-5042, Herger, Aline; https://orcid.org/0000-0003-1043-6441, Hou, Xiaoyu; https://orcid.org/0009-0000-0216-4648, Schaufelberger, Myriam; https://orcid.org/0000-0003-4060-7870, Roulard, Romain; https://orcid.org/0000-0002-3200-7130, Diet, Anouck; https://orcid.org/0009-0002-7612-4168, Roffler, Stefan, Lefebvre, Valérie; https://orcid.org/0000-0003-4482-3810, Wicker, Thomas; https://orcid.org/0000-0002-6777-7135, Pelloux, Jérôme; https://orcid.org/0000-0002-9371-1711, Ringli, Christoph; https://orcid.org/0000-0002-5533-2235, Gupta, Shibu; https://orcid.org/0000-0003-0412-7423, Guérin, Amandine; https://orcid.org/0000-0001-7143-5042, Herger, Aline; https://orcid.org/0000-0003-1043-6441, Hou, Xiaoyu; https://orcid.org/0009-0000-0216-4648, Schaufelberger, Myriam; https://orcid.org/0000-0003-4060-7870, Roulard, Romain; https://orcid.org/0000-0002-3200-7130, Diet, Anouck; https://orcid.org/0009-0002-7612-4168, Roffler, Stefan, Lefebvre, Valérie; https://orcid.org/0000-0003-4482-3810, Wicker, Thomas; https://orcid.org/0000-0002-6777-7135, Pelloux, Jérôme; https://orcid.org/0000-0002-9371-1711, and Ringli, Christoph; https://orcid.org/0000-0002-5533-2235

Abstract

Plant cell growth involves coordination of numerous processes and signaling cascades among the different cellular compartments to concomitantly enlarge the protoplast and the surrounding cell wall. The cell wall integrity-sensing process involves the extracellular LRX (LRR-Extensin) proteins that bind RALF (Rapid ALkalinization Factor) peptide hormones and, in vegetative tissues, interact with the transmembrane receptor kinase FERONIA (FER). This LRX/RALF/FER signaling module influences cell wall composition and regulates cell growth. The numerous proteins involved in or influenced by this module are beginning to be characterized. In a genetic screen, mutations in Apyrase 7 (APY7) were identified to suppress growth defects observed in lrx1 and fer mutants. APY7 encodes a Golgi-localized NTP-diphosphohydrolase, but opposed to other apyrases of Arabidopsis, APY7 revealed to be a negative regulator of cell growth. APY7 modulates the growth-inhibiting effect of RALF1, influences the cell wall architecture and -composition, and alters the pH of the extracellular matrix, all of which affect cell growth. Together, this study reveals a function of APY7 in cell wall formation and cell growth that is connected to growth processes influenced by the LRX/RALF/FER signaling module.

Published
2024

5. Growth-inhibiting effects of the unconventional plant APYRASE 7 of Arabidopsis thaliana influences the LRX/RALF/FER growth regulatory module

Author

Gupta, Shibu, primary, Guérin, Amandine, additional, Herger, Aline, additional, Hou, Xiaoyu, additional, Schaufelberger, Myriam, additional, Roulard, Romain, additional, Diet, Anouck, additional, Roffler, Stefan, additional, Lefebvre, Valérie, additional, Wicker, Thomas, additional, Pelloux, Jérôme, additional, and Ringli, Christoph, additional

Published
2024
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6. Seasonal Variation in Cell Wall Composition and Carbohydrate Metabolism in the Seagrass Posidonia oceanica Growing at Different Depths

Author

Ismael, Marwa, primary, Charras, Quentin, additional, Leschevin, Maïté, additional, Herfurth, Damien, additional, Roulard, Romain, additional, Quéro, Anthony, additional, Rusterucci, Christine, additional, Domon, Jean-Marc, additional, Jungas, Colette, additional, Vermerris, Wilfred, additional, and Rayon, Catherine, additional

Published
2023
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8. Combined LC-MS/MS and Molecular Networking Approach Reveals Antioxidant and Antimicrobial Compounds from Erismadelphus exsul Bark

Author

Essono Mintsa, Morel, primary, N’nang, Elvis Otogo, additional, Choque, Élodie, additional, Siah, Ali, additional, Jacquin, Justine, additional, Muchembled, Jerome, additional, Molinié, Roland, additional, Roulard, Romain, additional, Cailleu, Dominique, additional, Beniddir, Mehdi A., additional, Obiang, Cédric Sima, additional, Ondo, Joseph-Privat, additional, Kumulungui, Brice, additional, and Mesnard, François, additional

Published
2022
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