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Flavonoid Glycosides (flavonoid + glycoside)
Selected AbstractsAn investigation of the homolytic saccharide cleavage of deprotonated flavonol 3- O -glycosides in a quadrupole ion trap mass spectrometerJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2008Barry D. Davis Abstract The trend in the extent of homolytic saccharide cleavage is reported for a series of deprotonated flavonol 3- O -glycosides upon collision-induced dissociation (CID) in a quadrupole ion trap mass spectrometer. The second-generation product ions from the primary [Y0], and [Y0, H],, product ions were also identified. It was determined that the structure of both the aglycon and the saccharide portions of the flavonoid glycoside are pivotal in inducing radical cleavage. In contrast to earlier work on this subject reported for a smaller group of flavonols, the correlation between the degree of B-ring hydroxylation and the extent of radical saccharide cleavage showed several notable exceptions in the present work. Homolytic cleavage was also investigated in the context of using tandem mass spectrometry to identify the aglycon portions of flavonoid glycosides. Copyright © 2008 John Wiley & Sons, Ltd. [source] Blue light inhibits stomatal development in soybean isolines containing kaempferol-3- O -2G -glycosyl-gentiobioside (K9), a unique flavonoid glycosidePLANT CELL & ENVIRONMENT, Issue 8 2000L. Liu-Gitz ABSTRACT Stomata have a fundamental role in controlling plant photosynthesis and transpiration, but very little is known about factors controlling stomatal differentiation and development. Lines of soybean that contain a specific flavonol glycoside, kaempferol-3- O -2-glycosyl-gentiobioside (K9), as well as greatly reduced stomatal density, especially on the adaxial epidermis, have been identified. The specific effects of blue light photoreceptors on stomatal development in K9 lines and their isoline pairs containing no K9 were studied. Low irradiances of blue light (7% of total photosynthetically active radiation) added to high irradiances from low-pressure sodium lamps strongly inhibited stomatal development on the adaxial epidermis of K9 lines, but not in isoline pairs differing putatively in only one gene and lacking K9. Overall, blue light slightly increased stomatal density on the abaxial epidermis in all isolines, demonstrating differential regulation of stomatal development in the upper and lower epidermis. Blue light also caused an increase in leaf area in all isolines, indicating that changes in stomatal density were not the non-specific result of alterations in leaf area. Morphological studies revealed that the blue light-induced reduction in stomatal density in K9 lines was due to reduced stomatal initiation as well as aborted or abnormal stomatal development. As the phytochrome photostationary state was kept constant, the results indicate that one or more blue light receptors are involved in the control of stomatal development. This system should be useful for the study of mechanisms controlling stomatal development, even if the photo-inhibitory response is unique to K9 lines. [source] The phytochemical analysis and antioxidant activity assessment of orange peel (Citrus sinensis) cultivated in Greece,Crete indicates a new commercial source of hesperidinBIOMEDICAL CHROMATOGRAPHY, Issue 3 2009Firas I. Kanaze Abstract The flavonoid content of several methanolic extract fractions of Navel orange peel (flavedo and albedo of Citrus sinensis) cultivated in Crete (Greece) was first analysed phytochemically and then assessed for its antioxidant activity in vitro. The chemical structures of the constituents fractionated were originally determined by comparing their retention times and the obtained UV spectral data with the available bibliographic data and further verified by detailed LC-DAD-MS (ESI+) analysis. The main flavonoid groups found within the fractions examined were polymethoxylated flavones, O- glycosylated flavones, C- glycosylated flavones, O- glycosylated flavonols, O- glycosylated flavanones and phenolic acids along with their ester derivatives. In addition, the quantitative HPLC analysis confirmed that hesperidin is the major flavonoid glycoside found in the orange peel. Interestingly enough, its quantity at 48 mg/g of dry peel permits the commercial use of orange peel as a source for the production of hesperidin. The antioxidant activity of the orange peel methanolic extract fractions was evaluated by applying two complementary methodologies, DPPH, assay and the Co(II)/EDTA-induced luminol chemiluminescence approach. Overall, the results have shown that orange peel methanolic extracts possess moderate antioxidant activity as compared with the activity seen in tests where the corresponding aglycones, diosmetin and hesperetin were assessed in different ratios. Copyright © 2008 John Wiley & Sons, Ltd. [source] An investigation of the homolytic saccharide cleavage of deprotonated flavonol 3- O -glycosides in a quadrupole ion trap mass spectrometerJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2008Barry D. Davis Abstract The trend in the extent of homolytic saccharide cleavage is reported for a series of deprotonated flavonol 3- O -glycosides upon collision-induced dissociation (CID) in a quadrupole ion trap mass spectrometer. The second-generation product ions from the primary [Y0], and [Y0, H],, product ions were also identified. It was determined that the structure of both the aglycon and the saccharide portions of the flavonoid glycoside are pivotal in inducing radical cleavage. In contrast to earlier work on this subject reported for a smaller group of flavonols, the correlation between the degree of B-ring hydroxylation and the extent of radical saccharide cleavage showed several notable exceptions in the present work. Homolytic cleavage was also investigated in the context of using tandem mass spectrometry to identify the aglycon portions of flavonoid glycosides. Copyright © 2008 John Wiley & Sons, Ltd. [source] Evaluation of glycosylation and malonylation patterns in flavonoid glycosides during LC/MS/MS metabolite profilingJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 5 2008P. Kachlicki Abstract Flavonoid conjugates constitute several classes of plant phenolic secondary metabolites including many isomeric compounds differing in the hydroxylation pattern and substitution of their rings with different groups such as alkyls, acyls or sugars. These compounds occur in plant tissues mainly as glycosides and in many cases it is necessary to have reliable and detailed information concerning the structure of these natural products. Our results were obtained using leaf extracts of Arabidopsis thaliana and Lupinus angustifolius in which different glycosides of flavones, flavonols and isoflavones are present. Analysis of collision-induced dissociation (CID)/MS/MS spectra of protonated [M + H]+, sodiated [M + Na]+ or deprotonated [M , H], molecules recorded during HPLC runs may bring needed information in this respect. However, registration of mass spectra of [M + Na]+ ions with a good efficiency is possible only after post-column addition of a sodium acetate solution to the LC column eluate. The retention of sodium cation on the saccharidic parts of the molecule is observed after the CID fragmentation. In many cases, the location of this cation on the glycan attached to C-3 hydroxyl group of flavonol led to assignment of its structure. Additionally, the determination of the structure of the aglycone and of the sequence of the glycan part was made possible through the CID data obtained from the [M + H]+ and [M , H], ions. CID spectra show a different order of sugar elimination from hydroxyl groups at C-3 and C-7 in flavonol glycosides isolated from A. thaliana leaves and give sufficient information to discriminate flavonoid O-diglycosides from flavonoid di-O-glycosides. Copyright © 2007 John Wiley & Sons, Ltd. [source] Direct stereochemical assignment of hexose and pentose residues in flavonoid O -glycosides by fast atom bombardment and electrospray ionization mass spectrometry,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 12 2002Filip Cuyckens Abstract Mass spectrometric methods have been developed which allow the direct stereochemical assignment of terminal monosaccharide residues in flavonoid O -glycosides without the need for chemical hydrolysis. Standards containing a glucose, galactose, mannose, xylose, arabinose or apiose residue were examined because these monosaccharides are by far the most commonly encountered in flavonoid glycosides. Following acetylation, the major peracetylated sugar related fragments, generated by fast atom bombardment (FAB) or electrospray ionization (ESI), were selected for collisional activation employing a broad range of collision energies. Both FAB and ESI proved to be useful as ionization techniques. Stereoselective fragmentation was achieved and allowed us clearly to differentiate and characterize isomeric monosaccharide residues. The method developed was successfully applied to an unknown flavonoid containing a terminal pentose and hexose residue which was isolated from Farsetia aegyptia. Copyright © 2002 John Wiley & Sons, Ltd. [source] Spasmolytic and antidiarrhoeal properties of the Yucatec Mayan medicinal plant Casimiroa tetrameriaJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 9 2005Michael Heinrich The Maya of the Yucatán peninsula commonly use the leaves of Casimiroa tetrameria for treating gastrointestinal disorders, notably diarrhoea and dysentery, as well as gastrointestinal cramps. The phytochemical investigation resulted in the isolation of 13 compounds: eight polymethoxylated flavonoids (two as minor components with a main constituent), four flavonoid glycosides and one furanocoumarin. In this study we used two well-established models in order to assess the gastrointestinal effects of C. tetrameria extracts and isolated compounds: the USSING-chamber, a pharmacological model for diarrhoea, and the isolated guinea pig ileum, a model for modulatory effects on ileum contraction. Extracts and the class of polymethoxylated flavonoids showed strong inhibitory effects in both models, which provides ex-vivo evidence for the use of this botanical drug in the treatment of several gastrointestinal problems, most notably diarrhoea. The crude extract, polymethoxylated flavonoid-rich fractions and the polymethoxylated flavonoids tested showed prominent antisecretory activity. Polymethoxylated flavonoid-rich fractions also inhibited the histamine-induced contractions in the guinea pig model. The effects are not due to a single compound, but to a large number of structurally related compounds that all contribute to the effect. [source] Preparative isolation and purification of three flavonoid glycosides from Taraxacum mongolicum by high-speed counter-current chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 4 2008Shuyun Shi Abstract A preparative high-speed counter-current chromatography (HSCCC) was successively applied to purify three flavonoid glycosides from the aerial part of Taraxacum mongolicum, a traditional Chinese medicine. Subsequent UV, MS, and NMR analyses have led to the characterization of three flavonoid glycosides including two new compounds isoetin-7- O -,- D -glucopyranosyl-2,- O -,- L -arabinopyranoside and isoetin-7- O -,- D -glucopyranosyl-2,- O -,- D -glucopyranoside, and a known compound, isoetin-7- O -,- D -glucopyranosyl-2,- O -,- D -xyloypyranoside, which were first isolated from T. mongolicum. The two-phase solvent system composed of ethyl acetate/n -butanol/water (2:1:3, v/v/v) was performed in HSCCC. Consequently, a total of 25.7 mg isoetin-7- O -,- D -glucopyranosyl-2,- O -,- L -arabinopyranoside, 19.1 mg isoetin-7- O -,- D -glucopyranosyl-2,- O -,- D -glucopyranoside, and 10.6 mg isoetin-7- O -,- D -glucopyranosyl-2,- O -,- D -xyloypyranoside were obtained with purity of 98.7, 98.3, and 99.1%, respectively, as determined by HPLC from 500 mg enriched extract after cleaning-up by polyamide resin. [source] DOSY NMR applied to analysis of flavonoid glycosides from Bidens sulphureaMAGNETIC RESONANCE IN CHEMISTRY, Issue 12 2009Edilene Delphino Rodrigues Abstract 2D DOSY 1H NMR has proved to be a useful technique in the identification of the molecular skeleton of the four major compounds of ethyl acetate extract of aerial parts of Bidens sulphurea (Asteraceae). The combination of this technique with HPLC, mass spectrometry and other NMR techniques enabled the identification of four flavonoid glycosides: quercetin-3- O -,- D -galactopyranoside, quercetin-3- O -,- D -glycopyranoside, quercetin-3- O -,- L -arabinofuranoside and quercetin-3- O -,- D -rhamnopyranoside. Copyright © 2009 John Wiley & Sons, Ltd. [source] Fragmentation pathways of acylated flavonoid diglucuronides from leaves of Medicago truncatulaPHYTOCHEMICAL ANALYSIS, Issue 3 2010ukasz Marczak Abstract Introduction , Flavonoids are important plant compounds occurring in tissues mostly in the form of glycoconjugates. Most frequently the sugar moiety is comprised of mono- or oligosaccharides consisting of common sugars like glucose, rhamnose or galactose. In some plant species the glycosidic moiety contains glucuronic acid and may be acylated by phenylpropenoic acids. Methodology , Flavonoid glyconjugates were extracted from leaves of Medicago truncatula ecotype R108 and submitted to analysis using high-performance liquid chromatography combined with high-resolution tandem (quadrupole-time of flight, QToF) mass spectrometry. Results , The studied leaf extracts contained 26 different flavonoid glycosides among which 22 compounds were flavone (apigenin, luteolin, chrysoeriol and tricin) glucuronides and 13 were acylated with aromatic acids (p -coumaric, ferulic or sinapic). The fragmentation pathways observed in positive and negative ion mass spectra differed substantially between each other and from these of flavonoid glycosides which did not contain acidic sugars. The application of high-resolution MS techniques allowed unequivocal differentiation between ions with the same nominal m/z values containing different substituents (e.g. ferulic acid or glucuronic acid). Eleven of the identified flavonoids have not been reported previously in this species. Perspectives , The presented unique fragmentation pathways of flavonoid glucuronates enable detection of these compounds in tissue extracts from different plant species. Copyright © 2009 John Wiley & Sons, Ltd. [source] Characterisation of new oligoglycosidic compounds in two Chinese medicinal herbsPHYTOCHEMICAL ANALYSIS, Issue 4 2002Sandra Apers Abstract A series of caffeic acid derivatives (3,5-dicaffeoyl-quinic acid, 3,4-dicaffeoyl-quinic acid, and 4,5-dicaffeoyl-quinic acid), and the new compound ,,3,4-trihydroxyphenethyl- O -[,-apiofuranosyl-(1,4)-,-rhamnopyranosyl-(1,3)]-(4- O -caffeoyl)-,-glucopyranoside (wedelosin), as well as three known flavonoid glycosides (quercetin 3- O -,-glucoside, kaempferol 3- O -,-apiosyl-(1-2)-,-glucoside, and astragalin or kaempferol 3- O -,-glucoside) were isolated from the Chinese medicinal herb Wedelia chinensis. Wedelosin showed an inhibitory activity on both the classical and the alternative activation pathway of the complement system. Another Chinese medicinal herb, Kyllinga brevifolia, yielded two known flavonoid glycosides [kaempferol 3- O -,-apiosyl-(1-2)-,-glucoside and isorhamnetin 3- O -,-apiosyl-(1-2)-,-glucoside], and a new quercetin triglycoside [quercetin 3- O -,-apiofuranosyl-(1,2)-,-glucopyranoside 7- O -,-rhamnopyranoside]. The latter compound showed a moderate anti-viral activity. Copyright © 2002 John Wiley & Sons, Ltd. [source] Identification and quantification of galloyl derivatives, flavonoid glycosides and anthocyanins in leaves of Pistacia lentiscus L.PHYTOCHEMICAL ANALYSIS, Issue 2 2002A. Romani Abstract Separation, identification and quantification of polyphenols was carried out on leaves of Pistacia lentiscus L., an evergreen member of the family Anacardiaceae, using semi-preparative HPLC, HPLC-photodiode array detection and HPLC-MS analysis, together with 1H- and 13C NMR. Three major classes of secondary metabolites were detected: (i) gallic acid and galloyl derivatives of both glucose and quinic acid; (ii) flavonol glycosides, i.e. myricetin and quercetin glycosides; and (iii) anthocyanins, namely delphinidin 3- O -glucoside and cyanidin 3- O -glucoside. Low amounts of catechin were also detected. The concentration of galloyl derivatives was extremely high, representing 5.3% of the leaf dry weight, and appreciable amounts of myricetin derivatives were also detected (1.5% on a dry weight basis). These findings may be useful in establishing a relationship between the chemical composition of the leaf extract and the previously reported biological activity of P. lentiscus, and may also assign a new potential role of P. lentiscus tissue extracts in human health care. Copyright © 2002 John Wiley & Sons, Ltd. [source] Antioxidant and antiinflammatory activities of Sideritis perfoliata subsp. perfoliata (Lamiaceae)PHYTOTHERAPY RESEARCH, Issue 4 2008Maria-Thiresia Charami Abstract Sideritis perfoliata L. subsp. perfoliata is a plant widely used in folk medicine in Greece since antiquity because of its antiinflammatory, antirheumatic, antiulcer, digestive and vasoprotective properties. Phytochemical investigations of the polar extracts afforded four flavonoid glycosides, four phenylpropanoic glycosides, caffeic acid and one iridoid, ajugoside. Reactive oxygen species (ROS) are implicated in the aetiology of several inflammatory processes. In the present study polar fractions and isolated compounds from S. perfoliata subsp. perfoliata were evaluated for their antioxidant activity using DPPH spectrophotometric and TBA lipid peroxidation assays, as well as for their antiinflammatory activity using the soybean lipoxygenase bioassay. All extracts and isolated compounds showed significant antioxidant and inhibitory activity against soybean lipoxygenase. These findings give support to the ethnopharmacological use of the plant in the treatment of several inflammatory ailments. Copyright © 2008 John Wiley & Sons, Ltd. [source] Additional antiprotozoal constituents from Cuphea pinetorum, a plant used in Mayan traditional medicine to treat diarrhoeaPHYTOTHERAPY RESEARCH, Issue 8 2005Fernando Calzada Abstract In addition to kaempferol and quercetin already found in the roots from Cuphea pinetorum, bioassay-guided fractionation of the crude extract of the aerial part of this species gave four flavonoid glycosides, quercetin-3- O - , -rhamnopyranoside, luteolin-7- O - , - d -glucopyranoside, apigenin-7- O - , - l -rhamnopyranoside and apigenin-7- O - , - d -glucopyranoside, as well as squalen and , -sitosterol. In vitro antiamoebic and antigiardial activities of isolated compounds indicated that kaempferol is the principal antiprotozoal agent in C. pinetorum. Based on finding this antiprotozoal inhibitor, flavonoids were studied in order to elucidate structure-activity relationships. These data suggest that kaempferol may play an important role in antidiarrhoeal activity of C. pinetorum. Copyright © 2005 John Wiley & Sons, Ltd. [source] Negative ion ,chip-based' nanospray tandem mass spectrometry for the analysis of flavonoids in glandular trichomes of Lychnophora ericoides Mart. (Asteraceae)RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 23 2008Leonardo Gobbo-Neto This paper reports a method for the analysis of secondary metabolites stored in glandular trichomes, employing negative ion ,chip-based' nanospray tandem mass spectrometry. The analyses of glandular trichomes from Lychnophora ericoides, a plant endemic to the Brazilian ,cerrado' and used in traditional medicine as an anti-inflammatory and analgesic agent, led to the identification of five flavonoids (chrysin, pinocembrin, pinostrobin, pinobanksin and 3- O -acetylpinobanksin) by direct infusion of the extracts of glandular trichomes into the nanospray ionisation source. All the flavonoids have no oxidation at ring B, which resulted in a modification of the fragmentation pathways compared with that of the oxidised 3,4-dihydroflavonoids already described in the literature. The absence of the anti-inflammatory and antioxidant di- C -glucosylflavone vicenin-2, or any other flavonoid glycosides, in the glandular trichomes was also demonstrated. The use of the ,chip-based' nanospray QqTOF apparatus is a new fast and useful tool for the identification of secondary metabolites stored in the glandular trichomes, which can be useful for chemotaxonomic studies based on metabolites from glandular trichomes. Copyright © 2008 John Wiley & Sons, Ltd. [source] Characterization of phenolic compounds in the Chinese herbal drug Tu-Si-Zi by liquid chromatography coupled to electrospray ionization mass spectrometry,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2005Min Ye Phenolic compounds are the major bioactive constituents of the Chinese herbal drug Tu-Si-Zi, which is prepared from the seeds of Cuscuta chinensis. However, seeds of C. australis also are offered under the name of this drug in the herb market. In order to make a comparison of their chemical constituents, the phenolic compounds of these two Cuscuta species were analyzed by high-performance liquid chromatography/diode-array detection/electrospray ion trap tandem mass spectrometry (HPLC/DAD/ESI-MSn). A total of 50 compounds were observed in the methanol extracts, including 23 flavonoids, 20 lignans and 7 quinic acid derivatives. These compounds were separated on a C18 column and identified or tentatively characterized based on UV spectra and MS fragmentation behavior. In contrast to previous reports, the phenolic patterns of these two Cuscuta species were found to be very different. Kaempferol and astragalin were the predominant constituents of C. australis, while hyperoside was the major compound in C. chinensis. Most of the identified compounds, especially the acylated flavonoid glycosides, have not previously been reported from Cuscuta species. In addition, a 30,Da neutral loss observed for flavonols was investigated and could be used to differentiate flavonoid isomers such as kaempferol and luteolin. The ESI-MS fragmentation behavior of furofuran lignans was also investigated, and a characteristic pathway is proposed. The large differences observed between the phenolic constituents of C. chinensis and C. australis strongly encouraged further comparison of the bioactivities of these two species. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||