Search results for "Isorhamnetin"

2021

Centaurothamnus maximus (family Asteraceae), is a leafy shrub indigenous to the southwestern Arabian Peninsula. With a paucity of phytochemical data on this species, we set out to chemically characterize the plant. From the aerial parts, two newly identified guaianolides were isolated: 3β-hydroxy-4α(acetoxy)-4β(hydroxymethyl)-8α-(4-hydroxy methacrylate)-1αH,5αH, 6αH-gual-10(14),11(13)-dien-6,12-olide (1) and 15-descarboxy picrolide A (2). Seven previously reported compounds were also isolated: 3β, 4α, 8α-trihydroxy-4-(hydroxymethyl)-lαH, 5αH, 6βH, 7αH-guai-10(14),11(13)-dien-6,12-olide (3), chlorohyssopifolin B (4), cynaropikrin (5), hydroxyjanerin (6), chlorojanerin (7), isorhamnetin (8), …

Effect of alpha-linolenic acid in combination with the flavonol quercetin on markers of cardiovascular disease risk in healthy, non-obese adults: A r…

2019

Abstract Objectives Alpha-linolenic acid (ALA) and quercetin are characteristic compounds in plant-based diets. Cardioprotective effects have been described for both substances, although a possible benefit of combining ALA and quercetin has not, to our knowledge, been evaluated yet. The aim of this study was to investigate the potential independent and additive effects of ALA and quercetin on blood pressure (BP) and lipid and glucose metabolism, as well as on biomarkers of inflammation, oxidative stress, and antioxidant status in healthy, non-obese men and women. Another aim was to examine whether chronic supplementation of supranutritional doses of quercetin would result in an accumulation…

Enriched cereal bars are more effective in increasing plasma quercetin compared with quercetin from powder-filled hard capsules

2011

The flavonol quercetin, is one of the major flavonoids found in edible plants. The bioavailability of quercetin in humans may be influenced by the food matrix in which it is consumed as well as by its chemical and physical form. The objective of the present study was to investigate the biokinetics of quercetin from quercetin-enriched cereal bars and quercetin powder-filled hard capsules. In a randomised, single-blinded, diet-controlled cross-over study, six healthy women aged 22–28 years took a single oral dose of approximately 130 mg quercetin equivalents from either quercetin-enriched cereal bars (containing 93·3 % quercetin aglycone plus 6·7 % quercetin-4′-glucoside) or quercetin powder-…

Gas chromatographic–mass spectrometric investigation of the chemical composition of beebread

2009

Beebread consumption has a very long tradition; however, its composition and bioactive properties have not been studied thoroughly up to now. This study is expected to expand the knowledge of chemical composition of this bee product as a natural remedy and functional food ingredient. With the help of successive extraction with organic solvents of different polarity, more than 200 compounds were extracted from five samples of beebread and then identified by GC-MS method. The content of some phenol compounds (p-coumaric acid, kaempherol, isorhamnetin) with antioxidant properties has been determined quantitatively. Different content of free aminoacids have been detected in the analyzed samples…

Characterisation of phenolic compounds in Algerian honeys by RP-HPLC coupled to electrospray time-of-flight mass spectrometry

2017

Abstract A total of 35 honey samples from different regions of Algeria were studied to determine their phenolic profiles. Phenolic compounds, products of the secondary metabolism of plants, were extracted with amberlite XAD-4 and analysed by liquid chromatography, with diode array detection and electrospray ionisation mass spectrometry in negative ion polarity. By using colorometric assays, Erica honeys showed the highest content of phenolic compounds and flavonoids (245 ± 54 mg GAE/100 g and 29 ± 6 mg QE/100 g, respectively). More than 30 compounds were identified in the honey samples studied including 14 phenolic acids and 16 flavonoids. In general, honey samples showed different chromato…

Flavonoids from Acacia pennata and their Cyclooxygenase (COX-1 and COX-2) Inhibitory Activities

2007

Two new flavonoids quercetin 4'-O-alpha-L-rhamnopyranosyl-3-O-beta-D-allopyranoside (1) and apigenin 6-C-[2''-O-(E)-feruloyl- beta-D-glucopyranosyl]-8-C-beta-glucopyranoside (2), along with the known isorhamnetin 3-O-alpha-L-rhamnopyranoside (3), kaempferol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside (4), and isovitexin (5) were isolated from the leaves of Acacia pennata Willd. (Mimosaceae) and tested for their anti-inflammatory activity. Their structures were determined by 1D and 2D NMR and mass spectrometry. They were tested for an inhibitory effect on COX-1 and COX-2, showing 60-90% inhibition at 10(-4) g/mL and 5-14% inhibition at 10(-4) g/mL, respectively.

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…

Metabolites from the Aerial Parts of the Sicilian Population of Artemisia alba

2013

Phytochemical investigation of the CH2Cl2 extract of the aerial parts of Artemisia alba Turra afforded one new irregular sesquiterpenoid, artemiric acid, and five known metabolites: hydroxydavanone, the coumarins isofraxidin and scopoletin, (6 S*,7 S*,10 R*)–6,10-dimethyl-7,10-epoxyocta-11-enoic acid and artalbic acid. From the MeOH extract three flavonoids were identified: chrysoeriol, quercetin and isorhamnetin. The possible biogenetic pathways of artemiric and artalbic acids are discussed.

Free radical scavenging abilities of flavonoids as mechanism of protection against mutagenicity induced by tert-butyl hydroperoxide or cumene hydrope…

2003

Mutagenicity induced by tert-butyl hydroperoxide (BHP) or cumene hydroperoxide (CHP) in Salmonella typhimurium TA102 was effectively reduced by flavonols with 3',4'-hydroxyl groups such as fisetin, quercetin, rutin, isoquercitrin, hyperoxide, myricetin, myricitrin, robinetin, and to a lesser extent also by morin and kaempferol (ID50=0.25-1.05 micromol per plate). With the exception of isorhamnetin, rhamnetin, morin, and kaempferol, closely similar results were obtained with both peroxides. Hydrogenation of the double bond between carbons 2 and 3 (dihydroquercetin, dihydrorobinetin) as well as the additional elimination of the carbonyl function at carbon 4 (catechins) resulted in a loss of a…

Two isorhamnetin triglycosides from Anthyllis sericea

1989

Abstract A fraction of a methanolic extract of aerial parts of Anthyllis sericea yielded vicenin 2 and the two new compounds isorhamnetin 3- O -(2- O -β-glucopyranosyl-6- O -α-rhamnopyranosyl)-β-galactopyranoside and isorhamnetin 3- O -(2- O -β-glucopyranosyl)-βl-galactopyranoside-7- O -β-glucopyranoside.