Rutin flavonol O-glycoside

Fig-1 Structures of naringenin (flavanone, 1), naringin (flavanone O-glycoside, 2) and rutin (flavonol O-glycoside, 3), ketoconazole (4), 7/3-hydroxycholesterol (5) and 25-hydroxycholesterol (6), resveratrol (7) and etoposide (8, VP-16)... 

Fig. 2 Structures of four flavonols of rutin (flavonol O-glycoside) (3), kaempferol (9), quercetin (10) and myricetin (11)...

Procyanidins with different degrees of polymerization such as dimers, trimers, and polymers from extracts of different natural sources were found to be nonmutagenic in the Salmonella mutagenesis assay. Moreover, the mutagenic impurity in procyanidin B-4 was isolated by reversed-phase high-performance liquid chromatography (HPLC). Procyanidin B-4 was identified as rutin (flavonol O-glycoside, 3) (Fig. 22) [55]. 

Rutin (= Quercetin 3-rutinoside Rutoside) (flavonol O-glycoside)... 

Rutin (= Quercetin 3-0-Rut Quercetin 3-0-Rha-Glc 3,5,7,3, 4 -Pentahydroxy-flavone 3- 0-Rut Rutoside) (flavonol O-glycoside) Salvianolic acid K (phenylpropanoid) Salviaflaside (glycosylated phenypropanoid) Scopoletin (= Chrysatropic acid Gelseminic acid 7-Hydroxy-6-methoxycoumarin ... 

Fig. I6A A methanoiic extract of Lespedezae herba (4) contains more highly glycosidated flavonoids (R, range 0.05-0.35) such as kaempferol- and/or isorhamnetin-rhamno-glucoside and rutin (Tl). The EtAc extract (5,6) contains the enriched yellow zones of flavon-C-glyco.sides such as isoorientin (R, -- 0.S/T3), orientin (R, — 0.65/T3) overlapped by isovitexin, a.s well as flavonol-O-glycosides such as lespedin, hyperoside, isoquerdtrin and querdtrin (Rf 0.6-0.8).

So the spectrum of rutin (quercetin-3-O-mtinoside, MW 610 da) is characterized by the presence of the sodium adduct (m/z 633) the molecular ion ([MH], m/z 611) is almost absent. Also, the abundance of the aglycone residue (miz 302) is low, indicating that the removal of the glucose residue is hindered. The same behavior can be observed for other flavonol-3-O-glycosides, as described for Ginkgo biloba and St. John s wort extracts (see Secs. II.A and II.B). 

The flavonols and their glycosides contribute to specific taste characteristics such as bitterness and astringency in berry fruits and their products (Shahidi and Naczk, 1995). The molecular structure of flavonols lacks the conjugated double bonds of the anthocyanins, and they are thereby colorless. They may, however, contribute to discoloration of berry fruits, as they are readily oxidized by O-phenoloxidase in the presence of catechin and chlorogenic acid. Discoloration may also occur as a consequence of complex formation with metallic ions. On the other hand, the flavonol glycoside rutin is known to form complexes with anthocyanins, thus stabilizing the color of these compounds. 

FIGURE 1. Effects of glycosidases on the mutagenicities of flavonol glycosides. Rutin (a) and astragalin (b) were preincubated with hesperidinase ( ), jS-glucosidase (O), or no addition (A), and the mutation assay was then carried out by the preincubation method with S-9 Mix and strain TA98. 

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