Characterization Of Flavonoid Glycosides Research Articles

Identification of Flavonoid Glycosides of Methanol Extract from Cucumis dipsaceus Ehrenb. (Fruit) by using HPLC-UV-ESI-MS Methods

The present work is to identify the Chemical Composition of methanolic extract from Cucumis dipsaceus Ehrenb. (Fruit) by using HPLC-UV-ESI-MS Methods. It is very proficient method with amalgamation of liquid chromatography attached to electrospray ionization mass spectrometry in tendem means with positive and negative ion recognition. This is a simple and rapid method for characterization of flavonoid glycosides by using Reversed Phase High Performance Liquid Chromatography coupled to Electrospray Ionization Quadropole Time – of – Flight Mass Spectrometry (RP-HPLC-ESI-Q-TOF-MS). The correctness of mass information generated by Q-TOF-MS jointly with the fragmentation blueprint of the complete scan sprint of MS/MS investigation has been a valuable tool to cautiously characterization of 12 flavonoid glycosides (Molecular weight: 497.04 (RT:3.586), 475.06 (RT:6.801), 393.48 (RT:12.594), 336.50 (RT:16.473), 723.00 (RT:17.774), 452.52(RT:18.253), 978.95 (RT: 25.665), 836.20 (RT: 26.889), 893.00 (RT: 27.925), 838.32 (RT: 31.592), 507.44 (RT: 31.592), 415.18, (RT:33.849) in the methanol extract of this fruit. All these flavonoid glycosides are the first time reported from fruit of Cucumis dipsaceus Ehrenb., and also highlighting the importance of this fruit as a rich source of likely flavonoid glycosides as antioxidants and hepatoprotective agent. It was concluded that these flavonoid glycosides were Myceritin -3-O- β -D-glucopyranoside (497), Apigenin 7 – O – 6’’ – O acetyl – β – D - glucopyranoside (475), 5,6 Dihydroxy 7,8 – dimethoxyapigenin - 6 – O – sulfate (393), 5-p-coumaroylquinic acid (336 or 338), 6’’ -O-(3-hydroxy-3- methylglutaroyl)-2’’ - O - pentosyl-C - hexosyl-luteolin (723), Catechin-3-O-glucoside (452), 3’,4’,5’,5,7 – Methyl derivative of quercetin 3 – O – (2” - feruloylglucosyl)(1->6) – [apiosyl1->2)] glucoside (978.859), Quercetin 3 – O – β – D -(6 – O – sinnapoyl – 2 – O - – O – β – D glucopyranosyl) glucopyranoside (833), Apigenin 7-O-(6''-dihydrogalloyl)-glucosyl-8-C-rhamnosyl-6-C-glucoside (893), precursor or isomer ion of Quercetin 3 – O – β – D -(6 – O – sinnapoyl – 2 – O - – O – β – D glucopyranosyl) glucopyranoside 838.32 , 3’,4’,7 – Methyl derivative of quercetin 3 – O – β – D - glucopyranoside (507) and 415 (Daidzein 7 – O – glucoside).

Characterization of flavonoid glycosides from rapeseed bee pollen using a combination of chromatography, spectrometry and nuclear magnetic resonance with a step-wise separation strategy

To identify the structures of flavonoid glycosides in bee pollen collected from rapeseed plants (Brassica napus L.), we utilised an approach that combined liquid chromatography–diode array detector–electrospray ionization–mass spectrometry (LC–DAD–ESI–MS) and nuclear magnetic resonance (NMR) technology with a step-wise separation strategy. We identified four constituents of high purity in rape bee pollen samples: (1) quercetin-3-O-β-D-glucosyl-(2→l)-β-glucoside, (2) kaempferol-3, 4′-di-O-β-D-glucoside, (3) 5, 7, 4′-trihydroxy-3′-methoxyflavone-3-O-β-D-sophoroside and (4) kaempferol-3-O-β-D-glucosyl-(2→l)-β-D-glucoside. This study will also provide useful reference standards for qualification and quantification of four flavonoid glycosides in natural products.

Characterization of flavonoid glycosides from fenugreek (Trigonella foenum-graecum) crude seeds by HPLC-DAD-ESI/MS analysis.

Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon.

Characterization of flavonoid glycosides in traveller's tree (Ravenala Madagascariensis S.) leaves by HPLC-DAD-ESI-MSn

Characterization of flavonoid glycosides in traveller's tree (Ravenala Madagascariensis S.) leaves by HPLC-DAD-ESI-MSn

Systematic screening and characterization of flavonoid glycosides in Carthamus tinctorius L. by liquid chromatography/UV diode-array detection/electrospray ionization tandem mass spectrometry

The traditional Chinese medicine (TCM) is a complex system, which always consists of numerous compounds with significant difference in the content and physical and chemical properties. In this paper, a screening method based on target molecular weights was developed to characterize the flavonoid glycosides in the flower of Carthamus tinctorius L. The screening tables of aglycone and glycan were designed, respectively, in order to select and combine freely. The multiple reaction monitoring (MRM) scan mode with higher sensitivity and selectivity was adopted in the screening, which benefit the characterization for the minor components. Seventy-seven flavonoid glycosides were screened out finally, and their structures were characterized by tandem mass spectrometric method in both positive and negative ion modes. The glycosylation mode, aglycone, sequence and/or the interglycosidic linkages of the glycan portion and glycosylation position were elucidated by the fragmentation rule in the MS. Numerous compounds screened out with this method showed the structure variety in secondary plant metabolites, and the purposeful screening systemically and subsequent structure characterization offered more information about the chemical constitutions of TCM.

Negative ion desorption chemical ionization mass spectrometry of flavonoid glycosides

Negative ion mass spectra of underivatized flavonoid O- and C-glycosides were recorded using desorption chemical ionization (DCI) at a low reagent gas pressure. Advantages and limitations of the method for the characterization of the mono-, di- and triglycosides are discussed. For all O-glycosides investigated, the aglycone moieties are found to be base anions. The molecular masses of the glycosides are indicated by the presence of [M]−. ions with fairly high abundances for monoglycosides, lower abundances for diglycosides and a very low intensity for triglycosides. In addition to the sugar moiety losses, anions which resulted from the stepwise elimination of water from the sugar moiety were also observed at m/z 290 or 306 in 1 6 linked bioses, m/z 127, 145 and 163 in deoxyhexose as well as m/z 161 and 143 in hexose. Those ions except ions due to the molecule and the retro-Diels–Alder cleavage of the aglycone moiety could not be found in electron ionization mass spectra. Consequently, information concerning the structure of the aglycone moiety could be obtained using the EI technique and of sugar moiety using the negative ion DCI technique; also the combined positive and negative ion was shown to be a good approach for the structural characterization of flavonoid glycosides.

Plant polyphenols—XIV. : Characterization of flavonoid glycosides by acidic and enzymic hydrolyses

The rates of hydrolysis of more than a hundred flavonoid glycosides have been measured, using N HCl, β-glucosidase, β-glucuronidase or anthocyanase. The results show that such measurements are useful (α) in distinguishing O- from C-glycosides, ( b) in characterizing flavonoids having sugars attached to more than one hydroxyl group, and ( c) for determining suitable conditions for the isolation of intermediate glycosides. Flavonols with glucuronic acid or glucose attached to the 7-hydroxyl are readily distinguished from those having rhamnose attached by their resistance to acid hydrolysis; times for complete hydrolysis are 180, 25 and 5 min respectively. β-Glucosidase attacks the 3-, 7- and 4′- O-glucosides of quercetin at the same rate, but preferentially removes glucose from the 7-hydroxyl group of quercetin 7-glucoside-3-sophoro-side. Anthocyanase hydrolyses anthocyanidin 3-galactosides, 3-glucosides and 3-(diglycosides) much more rapidly than 3-rhamnosides, 3-arabinosides and acylated glycosides. These procedures have been applied, in combination with other methods, to the identification of flavonol glycosides present in species Allium, Helleborus, Lathyrus, Matthiola, Potentilla and Tulipa. New glycosides now characterized are: the 7-glucuronide-3-rutinosides of kaempferol and quercetin, the 7-rhamnoside-3-lathyroside and 7-rhamnoside-3-(rhamnosylarabinoside) of kaempferol, and the 7-glucoside-3-(xylosyl-glucoside), the 3,4′-diglucoside, the 3,7-diglucuronide and the 7-glucoside-3-(caffeoylsophoroside) of quercetin.