Glycoside flavonoid

Polyethylene glycol 4000 flavonoide glycosides no information dipping solution, 5% in ethanol, phytochemical investigations [273]... 

Several complexes of [Bu2Sn(IV)] with flavonoid glycosides 3-[6-0-(6-deoxy-a-L-mannopyranosyl)-(jS-D-glucopyranosyl)oxy]-2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4-H-l-benzopyran-4-one (rutin) and 2, 4, 3-trihydroxy-5, 4-dimetoxychalcone 4-rutinoside (hesperidin) and flavonoid aglycones (quercetin, morin, hesperitin, and other flavones) (Figure 5) were prepared. 

A recent phytogeny of the genus (Soltis et al., 2001) revealed that the South American taxa are most closely related to species from eastern Asia. In terms of flavonoid profiles, this requires us to reappraise the significance of the simple compounds. Thus, as suggested above, the simple flavonoid glycoside profile of C. valdivicum appears to represent a loss of biosynthetic capacities, in particular, extra oxygenation, and not a simple profile to which structural features were added in later stages of evolution. 

Flavonoids glycosides of the genus were also studied in detail and again L. tridentata, with 17 of the 18 identified compounds, exhibited the most complex array. The close relationship between L. tridentata and L. divaricata was again... 

The chemical formulae for a variety of plant phenols are given in Fig. 16.2, including examples of simpler phenols, such as cinnamic acid derivative, and of tocopherols, flavonoids, flavonoid glycosides and anthocyanidins. The flavonoids include the following subclasses flavanones (taxifolin), flavones (luteolin), flavonols (quercetin) and flavanols (catechin/epicatechin). The... 

Knowledge of the identity of phenolic compounds in food facilitates the analysis and discussion of potential antioxidant effects. Thus studies of phenolic compounds as antioxidants in food should usually by accompanied by the identification and quantification of the phenols. Reversed-phase HPLC combined with UV-VIS or electrochemical detection is the most common method for quantification of individual flavonoids and phenolic acids in foods (Merken and Beecher, 2000 Mattila and Kumpulainen, 2002), whereas HPLC combined with mass spectrometry has been used for identification of phenolic compounds (Justesen et al, 1998). Normal-phase HPLC combined with mass spectrometry has been used to identify monomeric and dimeric proanthocyanidins (Lazarus et al, 1999). Flavonoids are usually quantified as aglycones by HPLC, and samples containing flavonoid glycosides are therefore hydrolysed before analysis (Nuutila et al, 2002). 

Flavonoids Flavonoids Flavonoid glycosides Isoprenylated flavones... 

The plant is known elaborate a series of quite unusual phenanthrene alkaloid derivatives, of which aristoliukine-C, aristofolin A and E, aristolochic acid-la methyl ester, and aristolochic acid. Other chemical constituents found in this plant are flavonoid glycosides such as kaempferol-3-O-rutinoside and quercetin kaempferol-3-O-rutinoside (3,4). Exposure to Aristolochiaceae family is associated with the development of cancer in humans. A significant advance is the toxicological effects of aristolochic acid has been provided by the work of Pezzuto et al. They showed that aristolochic acid is a mutagen... 

Cuyckens F and Claeys M. 2002. Optimization of a liquid chromatography method based on simultaneous electrospray ionization mass spectrometric and ultraviolet photodiode array detection for analysis of flavonoid glycosides. Rapid Commun Mass Spectrom 16(24) 2341—2348. 

Stobiecki M. 2000. Application of mass spectrometry for identification and structural studies of flavonoid glycosides. Phytochemistry 54(3) 237-256. 

Identification of flavonoids Quantification of individual flavonoids depends heavily on the availability of standard references. Only a limited number of common flavonoids are commercially available as standards. Standard references for flavonoid glycosides are particularly difficult to find thus direct quantification of the native glycosides is nearly impossible. Analysis of the aglycones after acid or enzymatic hydrolysis is therefore common practice. When standard flavonoids are not available, or when unknown compounds are encountered in a particular fruit or vegetable, use of a DAD... 

Pietta PG, Mauri PL, Manera E and Ceva PL. 1989. HPLC determination of the flavonoid glycosides from Betulae folium extracts. Chromatographia 28 311—312. 

The primary limitation associated with GC/MS is the need for derivatization. Derivatization introduces additional complexity to the system and is not 100% efficient. Inefficient reactions result in the presence of multiple derivatized forms of the same compound. For example, we can detect three different derivatization products of the amino acid asparagine (mw = 132) in M. truncatula roots (Fig.3.4). These include asparagine, N,0-TMS (mw = 276), asparagine, N,N,0-TMS (mw = 348), and asparagine, N,N,N,0-TMS (mw = 420). Inefficiency of the derivation reactions also limits the lower concentration range of analytes that can be profiled. Finally, derivatization is not capable of achieving volatility for all compounds, such as many of the flavonoid glycosides. If derivatization is successful and the analyte is... 

Flavonoid aglycones (isolated by acid hydrolysis of the corresponding flavonoid glycosides)... 

It was stated that the chromatographic analysis of the flavonoid profde may help the determination of taxonomic relationships between these species [125], The optimization of the separation of flavonoid glycosides of Mentha piperita (Laminaceae) was carried out on silica, amino, cyano and C18 HPTLC statinoary phases. The investigation was motivated by the spasmolytic, carminative and cholagogue characteristics of the plant. Air-dried and powdered leaves of peppermint (300 g) were extracted with methanol-water 1 1 v/v at ambient temperature. The suspension was filtered, concentrated to 200 ml acidified to pH 3 with formic acid and separated in an ODS column (400 X 40 mm i.d. particle size 40 pm). 

The separation characteristics of unmodified silica, diol, cyano, cellulose and RP-18 stationary phases were compared for the analysis of ellagitannins, gallotannins and flavonoid glycosides in the aerial parts of Erodium cicutarum (Geraniaceae) (stork s bill). Its decoction has been used in cases of dysentery, fever, wounds and worm infections. The air-dried and powdered plant material (300 g) was extracted three times with water-acetone (1 1, v/v) at ambient temperature. The collected extract was filtered and concentrated. The aqueous phase was acidified to pH 3 with formic acid and separated in an ODS column. Polphenols... 

I. Fecka, A. Kowalczyk and W. Cisowski, Optimization of the separation of flavonoid glycosides and rosmarinic acid from Mentha piperita on HPTLC plates. J. Plan. Chromatogr.— Mod. TLC 17 (2004) 22-25. 

Flavonoid glycosides Kaempferol Quercetin Apigenin Luteolin Myricetin... 

Wojcicki J, Gawroska-Szkiarz B, Bieganowski W, Patalan M, Smulski HK, Samochowiec L, Zakrzewski J. (1995). Comparative pharmacokinetics and bioavailability of flavonoid glycosides of Ginkgo biloba after a single oral administration of three formulations to healthy volunteers. Materia Med Polona. 27(4) 141-46. 

FIGURE 7.11 NMR spectrum of one of the five relatively rare flavonoid glycosides in an extract of Rhaponticum carthamoides, obtained by LC-SPE-NMR technique. (Reproduced from Miliauskas, G. et al. J. Nat. Prod. 2005, 68, 168-172. Copyright (2005). With permission American Chemical Society.)... 

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