Flavonols glycosides

An examination of the flavonoids of Villarsia (Bohm et al., 1986) revealed a heterogeneous array of flavonol glycosides, based upon kaempferol, quercetin, and isorhamnetin, with each species exhibiting a unique assortment. Surprisingly, there were greater similarities between the pigment profile of V capensis and species from eastern Australia, V exaltata (Soland. ex Sims) G. Don from Tasmania and V. reniformis R. Br. from New South Wales, than with species native to... 

A detailed study of the flavonoid chemistry of the island endemics, the closely related G. tinctoria, and live additional species from the mainland provided additional evidence pointing toward G. tinctoria as the ancestral species (Pacheco et al., 1993). The flavonoid profiles of all species consisted of flavonol glycosides as major components with an unidentified flavone glycoside and several unidentified phenolic compounds (presumably not flavonoids). The pattern of distribution of the flavonol glycosides and unidentified flavones within the set of nine species proved to be extremely informative. (The phenols were ubiquitous and are not considered further.) Kaempferol glycosides were seen in neither the island species nor G. tinctoria, but were present, in several combinations, in the rest of the mainland taxa. The isorhamnetin glycosides showed the reverse pattern, with one exception the island endemics and G. tinctoria exhibited these compounds, whereas four of the other mainland species did not. The sole exception is G. boliviari, which exhibited one of the isorhamnetin derivatives. 

Table 6.3 Flavonol glycoside profiles of Juan Fernandez Islands species of Gunnera compared to species from South America and Mexico (from Pacheco et al., 1993)...

Blemosperma nanum var. robustum lacked the flavone, but exhibited the flavonol glycosides plus cyanidin 3-0-monoglycoside [stracture 561] in some individuals. 

As relatively few standard compounds are available from commercial or other sources, identification of flavonol glycosides has to be achieved by alternative means, for example UV-, H- and C-NMR spectroscopy. Therefore hydrolysing all glycosides to aglycones followed by HPLC determination offers a practical method for the quantitative determination of flavonoids in tea (Hertog et al, 1993a Wang and Helliwell, 2001). 

FINGER A, ENGELHARDT u H and WRAY V (1991) Flavonol glycosides in tea - kaempferol and quercetin rhamnodiglucosides , J Sci Food Agric, 55, 313-21. 

PRICE K R, RHODES M j c and BARNES K A (1998) Flavonol glycoside content and composition of tea infusions made from commercially available teas and tea products , J Agric Food Chem, 46, 2517-22. 

PRICE K R, CASUSCELLi F, coLQUHOUN IJ and RHODES M J c (1998) Composition and content of flavonol glycosides in broccoli florets (Brassica olearacea) and their fate during cooking , J Sci Food Agric, 11 (4) 468-72. 

The effects of catechin, epicatechin, procyanidin B2, caffeic acid, / -coumaric acid, myricetrin, and quercetrin on the color intensity and stability of malvidin 3-glucoside at a molar ratio of 1 1 under conditions similar to red wine were evaluated. " Flavan 3-ols appeared to have the lowest protective effects and flavonols the highest strong color changes were visually perceptible. " In the complexation of malvin chloride and natural polyphenols, flavonol glycosides by far exerted the best protector effect. ... 

Sagesser, M. and Deinzer, M., HPLC-ion spray-tandem mass spectrometry of flavonol glycosides in hops, J. Am. Soc. Brew. Chem., 54, 129, 1996. 

M. J. Dubber, V. Sewram, N. Mshicileli, G.S. Shephard and I. Kanfer, The simultaneous determination of selected flavonol glycosides and aglycones in Ginkgo biloba oral dosage forms by high performance liquid chromatography electrospray ionization mass spectrometry, J. Pharmaceut. Biomed., 37, 723 731 (2005). 

Wang J and Sporns P. 2000a. MALDI-TOF MS analysis of food flavonol glycosides. J Agric Food Chem... 

RETENTION TIMES AND TENTATIVE STRUCTURES OF FLAVONOL GLYCOSIDES IN THE UNHYDROLYSED BERRY EXTRACTS... 

Direct injection API-Electrospray MS is capable of analyzing much larger and less volatile substances than either EI/MS or CI/MS. As a result, this method is often used to provide structural information on peptides, proteins, and polymers derived from both natural and synthetic processes it is also useful in the analysis of many natural compounds including molecules such as saponins and flavonol glycosides, derived from plants. When using direct injection API-electrospray, partial purification and EC preparation are performed elsewhere and a collected fraction is dissolved in an appropriate solvent and injected as a bolus into the mass spectrometer (flow or direct injection or syringe infusion). This has an advantage, as the mass... 

Cnshnie TP, Hamilton VE, Chapman DG Taylor PW, Lamb AJ. (2007) Aggregation of Staphylococcus aureus following treatment with the antibacterial flavonol glycoside galangin. J Appl Microbiol 103 1562-1567. 

Kim HY, Moon BH, Lee HI, Choi DH. (2004) Flavonol glycosides from the leaves of Eucommia ulmoides O. with glycation inhibitory activity. J Ethnopharm 93 227-230. 

After hydrolysis of the obtained flavonol glycosides, flavonol aglycones and sugars were identified by HPLC and gas chromatography-mass spectrometry (GC-MS), respectively. (109 words)... 

Zuo, Y. Chen, H. Deng, Y. Isolation and Identification of Flavonol Glycosides in American Cranberry Fruit using HPLC and GC-MS. Proceedings of the 233rd American Chemical Society National Meeting, Chicago, IL, March 25-29, 2007. 

The raison d etre for the proliferation of flavone and flavonol glycosides in nature continues to intrigue plant scientists. The ability of UV-B radiation to damage DNA, RNA, and proteins as well as to impair processes like photosynthesis is well known. Most flavonoids are very efficient antioxidants and chemoprotectants, and are therefore used in a plethora of food supplements and nutraceuticals [30]. Some flavonoids, however, have a Janus face - they could be excellent antioxidants but also have negative features. 

Ishikura, N. Flavonol glycosides in the flowers of Hibiscus mutahilis f. versicolor. Agr Biol Chem 1982 46 1705-1706. Smith, R. M., and]. M. Robinson. The essential oil of ginger from Fiji. Phytochemistry 1981 20 203-206. Anon. Analgesic formulations containing shogaol and gingerol. Patent-Japan Kokai Tokkyo Koho-82 46,914 1982 5 pp. 

Modifications of the method (dry-column chromatography, vacuum liquid chromatography, VLC, for example) are also of practical use for the rapid fractionation of plant extracts. VLC with a polyamide support has been reported for the separation of flavonol glycosides. ... 

Flavonol glycosides from Epilobium species RP-18 15-25 p,m 460 X 26 mm MeOH-H20, 35 65 38... 

The technique of CPC was also employed as a key step in the purification of 26 phenolic compounds from the needles of Norway spruce (Picea abies, Pinaceae). An aqueous extract of needles (5.45 g) was separated with the solvent system CHCl3-Me0H-i-Pr0H-H20 (5 6 1 4), initially with the lower phase as mobile phase and then subsequently switching to the upper phase as mobile phase. Final purification of the constituent flavonol glycosides, stilbenes, and catechins was by gel filtration and semipreparative HPLC. °... 

Flavonoids from Hippophae rhamnoides Flavonol glycosides from Vernonia galamensis Flavonol glycosides from Picea abies Flavonol glycosides from Polypodium decumanum Flavone C-glycosides from Cecropia lyratiloba... 

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