Search results for "Flavonoids"
showing 10 items of 213 documents
COX-2 and sPLA2 inhibitory activity of aqueous extract and polyphenols of Rhizophora mangle (red mangrove)
2006
The aqueous extract of Rhizophora mangle bark and its polyphenolic fractions showed remarkable in vitro antiinflammatory activity in a preliminary study. The low molecular weight fraction exhibited cyclooxygenase-2 inhibitory activity while the total aqueous extract and the low molecular weight fraction showed secretory phospholipase A(2) inhibitory activity.
A density functional study of flavonoid compounds with anti-HIV activity.
2005
Abstract Quantum chemical calculations at the DFT/B3LYP theory level, with the 6-31G* basis set, was employed to calculate a set of molecular properties of 26 flavonoid compounds with anti-HIV activity. The correlation between biological activity and structural properties was obtained by using the multiple linear regression method. The model obtained showed not only statistical significance but also predictive ability. We demonstrate in this paper that the anti-HIV activity of compounds can be related with the molecular hydrophobicity (ClogP), the electronegativity ( χ ) and the charges on some key atoms, while that the toxicity can be related with the electronic affinities (EA), ClogP and …
Antibacterial activity of flavonoids and phenylpropanoids from Marrubium globosum ssp. libanoticum.
2006
Marrubium globosum Montbr. et Auch. ex Benth. ssp. libanoticum Boiss. (Lamiaceae) is a medicinal plant used for the treatment of inflammatory diseases, asthma, coughs and other pulmonary and urinary problems. The goal of our study was to assess the biological activity of M. globosum testing the methanol extract of aerial parts for its antibacterial activity against bacteria known to cause respiratory, gastrointestinal, skin and urinary disorders; the extract showed antibacterial effects against all the strains of bacteria used. A purification of this active extract showed the presence, as main constituents, of verbascoside, isorhamnetin 3-O-beta-D-rutinoside, quercetin 3-O-beta-D-rutinoside…
Analytical procedure elaboration of total flavonoid content determination and antimicrobial activity of bee bread extracts
2019
Sixteen ethanolic extracts were obtained from seven different bee bread samples. The total flavonoid content in the extracts was determined by aluminium-chloride method and was in the range of 8.3 mg/L ± 6.24% to 195.3 mg/L ± 1.35% and 28.8 mg/L ± 19.33% to 603.3 mg/L ± 4.64% with reference to quercetin and rutin, respectively. The relative standard deviations (RSD) for parallel measurements for the calibration curves of quercetin dehydrate and rutin trihydrate were in the range of 0.51% to 9.39% and 5.02% to 19.91%, respectively. The RSD for parallel measurements for the extracts with reference to quercetin dihydrate and rutin trihydrate were in the range of 0.23% to 11.64% and 4.64% to 19…
Physyological role of t-PMET in erythrocytes redox homeostasis: influence of flavonoids
2013
PHYSYOLOGICAL ROLE OF t-PMET IN ERYTHROCYTES REDOX HOMEOSTASIS:INFLUENCE OF FLAVONOIDS D. Di Majo1, M. La Guardia2, M. Crescimanno1, C. Flandina1, G. Leto1, M. Giammanco1 1Unità Didattico Scientifica di Fisiologia e Farmacologia, Dip. DIGSPO, Università di Palermo; 2Dip. STEBICEF, Università degli Studi di Palermo. Corresponding author: Danila Di Majo, Unità Didattico Scientifica di Fisiologia e Farmacologia, Dip. DIGSPO,Università degli Studi di Palermo. e-mail. danila.dimajo@unipa.it, phone +390916236405 Background In the last decade the trans-Plasma Membrane Electron Transport (t-PMET) has been subject to more research. Ever growing evidence has demonstrated that t-PMET occurs in all typ…
Plant Occurring Flavonoids as Modulators of the Aryl Hydrocarbon Receptor
2021
International audience; The aryl hydrocarbon receptor (AhR) is a transcription factor deeply implicated in health and diseases. Historically identified as a sensor of xenobiotics and mainly toxic substances, AhR has recently become an emerging pharmacological target in cancer, immunology, inflammatory conditions, and aging. Multiple AhR ligands are recognized, with plant occurring flavonoids being the largest group of natural ligands of AhR in the human diet. The biological implications of the modulatory effects of flavonoids on AhR could be highlighted from a toxicological and environmental concern and for the possible pharmacological applicability. Overall, the possible AhR-mediated harmf…
Prenylated Flavonoids from the Roots of Tephrosia rhodesica
2020
Five new compounds—rhodimer (1), rhodiflavan A (2), rhodiflavan B (3), rhodiflavan C (4), and rhodacarpin (5)—along with 16 known secondary metabolites, were isolated from the CH2Cl2–CH3OH (1:1) extract of the roots of Tephrosia rhodesica. They were identified by NMR spectroscopic, mass spectrometric, X-ray crystallographic, and ECD spectroscopic analyses. The crude extract and the isolated compounds 2–5, 9, 15, and 21 showed activity (100% at 10 μg and IC50 = 5–15 μM) against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum. peerReviewed
Resveratrol, a polyphenolic phytoalexin present in red wine, enhances expression and activity of endothelial nitric oxide synthase.
2002
Background— Estrogens can upregulate endothelial nitric oxide synthase (eNOS) in human endothelial cells by increasing eNOS promoter activity and enhancing the binding activity of the transcription factor Sp1. Resveratrol, a polyphenolic phytoalexin found in grapes and wine, has been reported to act as an agonist at the estrogen receptor. Therefore, we tested the effect of this putative phytoestrogen on eNOS expression in human endothelial cells. Methods and Results— Incubation of human umbilical vein endothelial cells (HUVEC) and HUVEC-derived EA.hy 926 cells with resveratrol for 24 to 72 hours upregulated eNOS mRNA expression in a time- and concentration-dependent manner (up to 2.8-fold)…
Simultaneous determination of main phenolic acids and flavonoids in tomato by micellar electrokinetic capillary electrophoresis
2017
[EN] A methodology for the determination of tomato phenolic acids and flavonoids has been developed combining MEKC and DAD detection. The influence on polyphenol separation of pH and background electrolyte, BGE (borax, acetonitrile, methanol and SDS concentrations), was studied and optimized using response surface methodology and weighted desirability function. Separation of polyphenols was achieved within 20 min at 15 degrees C using 11.3 mM borax and 11.2 mM SDS adjusted to pH 8.5 as BGE. Validation was performed using standards and tomato extracts. Recoveries ranged from 77 to 106%. Acceptable repeatabilities were obtained for peak area (% RSD <3.1% and <3.7%) and migration times (% RSD …
Therapeutic potential of dietary polyphenols against brain ageing and neurodegenerative disorders
2010
In recent years there has been a growing interest, supported by a large number of experimental and epidemiological studies, in the beneficial effects of some commonly used food-derived products in preventing various age-related pathologic conditions, ranging from cancer to neurodegenerative diseases. Spices and herbs often contain active phenolic substances endowed with potent antioxidative and chemopreventive properties. Curcumin is a phytochemical compound extracted from the rhizome of Curcuma Longa. It is the pigment responsible for the characteristic yellow color of Indian curry. Data from our and other laboratories demonstrated that curcumin, as well as some other polyphenols, strongly…