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1.
Acta cir. bras. ; 35(6): [e202000602], jul. 2020. tab, graf
Article de Anglais | VETINDEX | ID: vti-29175

RÉSUMÉ

Purpose. To examine the effects of quercetin on healing of experimental colon anastomosis injury in early and late period.. Methods. Eighty male Wistar-Albino rats were divided into 8 groups. For all groups, left colons of the rats were resected and for the rest end-to-end anastomosis was performed. Two of the groups for which the experiment protocol was ended on the 3rd and 7th day following the anastomosis were not administered with either quercetin or dimethylsulfoxide DMSO, whereas two other groups were administered with DMSO only, and four other groups were administered with quercetin dissolved in DMSO in doses of 20 and 100 mg/kg during the protocol. At the end of the study, anastomosis line was resected, histopathological evaluation was performed and bursting pressure, malondialdehyde, superoxide dismutase, catalase, and hydroxyproline levels were measured.. Results. Quercetin significantly increased hydroxyproline, superoxide dismutase, catalase levels, histopathological healing score, bursting pressure values and decreased malondialdehyde level in early period. It also significantly increased superoxide dismutase, catalase, and hydroxyproline levels and decreased malondialdehyde level in late period. Conclusion: It was seen that quercetin speeds up the injury healing process and reveals an antioxidant effect, specifically in early period.(AU)


Sujet(s)
Animaux , Rats , Rats/traumatismes , Anastomose chirurgicale/médecine vétérinaire , Quercétine/biosynthèse , Antioxydants
2.
Molecules ; 21(1): 92, 2016 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-26784158

RÉSUMÉ

A small Chilean variety of pears growing in the town of Toconao, an oasis located at the northeastern edge of the Salar de Atacama, northern Chile, was studied by means of modern PDA and high resolution mass spectral data (UHPLC-PDA-HESI-orbitrap-MS/MS). In addition, the antioxidant features of the fruits were compared with the varieties Packhman's Triumph and Abate Fetel and correlated with the presence of phenolic compounds. The non-pigmented phenolics were fingerprinted and related to the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics and flavonoids measured by spectroscopic methods. The machine allowed a fast separation of 15 min employing a flow rate of 1 mL per minute and could accurately identify 25 compounds, including several isorhamnetin derivatives and phenolic acids, present in the peel and pulps of this Chilean variety for the first time. The compounds were monitored using a wavelength range of 210-800 nm. The native small Chilean pear showed the highest antioxidant activity measured as the bleaching of the DPPH radical, the ferric reducing antioxidant power and superoxide anion scavenging activity (8.61 ± 0.65 µg/mL, 712.63 ± 12.12 micromols trolox equivalents (µmol/TE)/100 g FW, and 82.89% ± 2.52% at 100 µg/mL, respectively).


Sujet(s)
Antioxydants/isolement et purification , Flavonoïdes/isolement et purification , Fruit/composition chimique , Phénols/isolement et purification , Pyrus/composition chimique , Quercétine/analogues et dérivés , Antioxydants/composition chimique , Antioxydants/métabolisme , Dérivés du biphényle/antagonistes et inhibiteurs , Dérivés du biphényle/composition chimique , Chili , Chromatographie en phase liquide à haute performance/instrumentation , Chromatographie en phase liquide à haute performance/méthodes , Climat désertique , Flavonoïdes/biosynthèse , Flavonoïdes/composition chimique , Phénols/composition chimique , Phénols/métabolisme , Picrates/antagonistes et inhibiteurs , Picrates/composition chimique , Extraits de plantes/composition chimique , Pyrus/métabolisme , Quercétine/biosynthèse , Quercétine/composition chimique , Quercétine/isolement et purification , Superoxydes/antagonistes et inhibiteurs , Superoxydes/composition chimique , Spectrométrie de masse en tandem/instrumentation , Spectrométrie de masse en tandem/méthodes
3.
Eur J Pharmacol ; 733: 75-80, 2014 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-24704375

RÉSUMÉ

In this work we report the vasorelaxant activity of 7-ß-O-glycosides obtained with biosynthesis of naringenin-7-ß-O-glycoside (3) and quercetin-7-ß-O-glycoside (4). These compounds were obtained from naringenin (1) and quercetin (2) glycosylation catalyzed by Beauveria bassiana ATCC 7159. Screening of the best strain as a catalyst for glycosylation was carried out and the reaction conditions established. Cultures were grown in PDSM medium for 7 days at 27 °C. After purification by reverse-phase preparative HPLC, naringenin-7-ß-O-glycoside (3) and quercetin-7-ß-O-glycoside (4) were identified by (1)H and (13)C NMR. The right position and ß-configuration of the glucose was determined through HSQC and HMBC experiments. The vasorelaxation potential of naringenin, quercetin and its glycosylated derivatives was evaluated using isolated aorta in vitro models. Interestingly, results suggest that vasorelaxation properties of naringenin, rutin and its glycosides are due to different pathways.


Sujet(s)
Flavanones/biosynthèse , Flavanones/pharmacologie , Flavonoïdes/composition chimique , Glucosides/biosynthèse , Glucosides/pharmacologie , Quercétine/analogues et dérivés , Vasodilatation/effets des médicaments et des substances chimiques , Vasodilatateurs/pharmacologie , Animaux , Aorte/effets des médicaments et des substances chimiques , Beauveria/métabolisme , Biocatalyse , Flavanones/composition chimique , Flavanones/métabolisme , Flavonoïdes/métabolisme , Glucosides/composition chimique , Glycosylation , Techniques in vitro , Mâle , Structure moléculaire , Quercétine/biosynthèse , Quercétine/composition chimique , Quercétine/isolement et purification , Quercétine/métabolisme , Quercétine/pharmacologie , Rat Wistar , Vasodilatateurs/isolement et purification
4.
Photochem Photobiol ; 89(2): 391-9, 2013.
Article de Anglais | MEDLINE | ID: mdl-23057576

RÉSUMÉ

Antioxidant compounds protect plants against oxidative stress caused by environmental conditions. Different light qualities, such as UV-A radiation and blue light, have shown positive effects on the production of phenols in plants. Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) is used for treating wounds and inflammations. Some of these beneficial effects are attributed to the antioxidant activity of plant components. We investigated the effects of blue light and UV-A radiation supplementation on the total phenol content, antioxidant activity and chromatographic profile of aqueous extracts from leaves of K. pinnata. Monoclonal plants were grown under white light, white plus blue light and white plus UV-A radiation. Supplemental blue light improved the antioxidant activity and changed the phenolic profile of the extracts. Analysis by HPLC of supplemental blue-light plant extracts revealed a higher proportion of the major flavonoid quercetin 3-O-α-L-arabinopyranosyl (1→2) α-L-rhamnopyranoside, as well as the presence of a wide variety of other phenolic substances. These findings may explain the higher antioxidant activity observed for this extract. Blue light is proposed as a supplemental light source in the cultivation of K. pinnata, to improve its antioxidant activity.


Sujet(s)
Antioxydants/métabolisme , Kalanchoe/effets des radiations , Phénols/métabolisme , Feuilles de plante/effets des radiations , Quercétine/analogues et dérivés , Kalanchoe/métabolisme , Lumière , Oxydoréduction , Extraits de plantes/composition chimique , Feuilles de plante/métabolisme , Quercétine/biosynthèse
5.
Biol Pharm Bull ; 31(12): 2321-5, 2008 Dec.
Article de Anglais | MEDLINE | ID: mdl-19043220

RÉSUMÉ

An efficient protocol for the in vitro germination and propagation of Larrea divaricata CAV. (Jarilla) was established. To determine the effect of different growth regulators on the growth rates and phenol production, apical-node microshoots from in vitro germinated plantlets were incubated on the following media: 1) full-strength MS (Murashige and Skoog) salt medium with different ratios of alpha-naphthaleneacetic acid (NAA) and N(6)-benzyladenine (BA); 2) after pre-treatment with indolebutyric acid (IBA), transfer to MS medium of different inorganic salt strengths; and 3) full-strength MS salt medium with different ratios of sucrose and IBA. Successful microshoot rooting percentages were achieved by the second and third strategies, the highest being 87.5-100%. The maximum principal shoot length and node number obtained by the second strategy corresponded to the plantlets previously induced with 50 microM IBA, and grown on half- or full-strength MS salt media (7.03+/-0.93 and 9.86+/-1.07 cm, respectively) while in the third strategy the most efficient micropropagation medium was full-strength MS salt medium supplemented with 7.5 microM IBA: 3% (w/v) sucrose (7.05+/-1.08 and 7.0+/-1.51 cm, respectively). The phenol concentration was determined by analytical HPLC. The highest content of nordihydroguiaretic acid (NDGA) accumulated in microplants of L. divaricata cultivated on half-strength MS salt medium (35.90+/-3.82 mg/g DW). Reducing the MS medium salt concentration by half, in the absence of IBA, it resulted in a higher NDGA production. NDGA production was not sensitive to the variation of IBA concentration. The medium supplemented with 5% (w/v) sucrose and 2.5 microM IBA induced not only a higher NDGA production but also a higher quercetin production.


Sujet(s)
Larrea/croissance et développement , Larrea/métabolisme , Techniques de culture de tissus/méthodes , Acclimatation , Milieux de culture , Germination , Racines de plante/croissance et développement , Racines de plante/métabolisme , Quercétine/biosynthèse , Quercétine/composition chimique , Graines/composition chimique , Solvants
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