Antioxidant flavonol glycosides from Schinus molle

Abstract

Chromatographic separation of aqueous MeOH extract of the leaves of Schinus molle L. has yielded two new acylated quercetin glycosides, named isoquercitrin 6''-O-p-hydroxybenzoate (12) and 2''-O-alpha-L-rhamnopyranosyl-hyperin 6''-O-gallate (13), together with 12 known polyphenolic metabolites for the first time from this species, namely gallic acid (1), methyl gallate (2), chlorogenic acid (3), 2''-alpha-L-rhamnopyranosyl-hyperin (4), quercetin 3-O-beta-D-neohesperidoside (5), miquelianin (6), quercetin 3-O-beta-D-galacturonopyranoside (7), isoquercitrin (8), hyperin (9), isoquercitrin 6''-gallate (10), hyperin 6''-O-gallate (11) and (+)-catechin (14). Their structures were established on the basis of chromatographic properties, chemical, spectroscopic (UV, 1H, 13C NMR) and ESI-MS (positive and negative modes) analyses. Compounds 4-9 and 11 exhibited moderate to strong radical scavenging properties on lipid peroxidation, hydroxyl radical and superoxide anion generations with the highest activities shown by 6 and 7 in comparison with that of quercetin as a positive control in vitro.

Phenolic Content of Albizia anthelmintica Leaves and Their Antioxidant and Cytotoxic Activity

“…The attachment of sugar to quercetin moiety was deduced to be at the 3-position from the down field-shifted carbon signal 156.99 (C-2), together with up field shift of C-3 at 133.92 indicate Oglycosidation at C-3. The attachment of galloyl moiety to OH-6`` proved by the down field shift of C-6`` at 63.70 and up field shift of C-5`` at 74.80 in -and 617.11 [M+H] + corresponding to the molecular weight 616.10 which support the evidence that Compound 8 is Quercetin 3-O-(6``-O-galloyl)-β-D-glucopyranoside which was in a good agreement with previously published data 13,17,18 . Compound 9 was obtained as yellow amorphous powder (39 mg).…”

“…A final confirmation of Compound 9 was achieved by comparison with previously published data. 13,17 Compound 9 was isolated once before from A. anthelmintica.…”

Plant-Derived Agents with Anti-Glycation Activity

“…It also demonstrated free radical scavenging properties [119]. Marzouk et al (2006) reported that hyperin strongly inhibited the formation of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals [117] and lipid peroxidation, as well as the hydroxyl radical and superoxide anion generation [120]. Also, hyperin inhibits lipopolysaccharide (LPS)-induced nitric oxide (NO) production [120].…”

“…More interestingly, flavonoids with the 3′,4′-dihydroxy group (i.e., quercetin and quercitrin) demonstrated the highest inhibitory activity against AGEs formation after incubation at 37°C for 14 days, with IC50 values much lower than that of AG [111]. Besides quercetin, the flavonoid glycosides isoquercitrin (quercetin-3-β-glucopyranoside) and hyperin (quercetin-3-D-galactoside) are well-known antioxidants [116][117][118]. Isoquercitrin showed outstanding antioxidant activity in yeast cells by increasing the activity of superoxide dismutase (SOD) [118].…”

Natural antioxidants isolated from Schinus areira leaves by ultrasound-assisted extraction

“…Quercetin, one of the flavonoids found widely in the human diet, has been reported to have many health benefits and it is a promising agent for the prevention of systemic inflammatory diseases such as sepsis (Chang, Tsai, Sheu, Hsieh, & Chiang, 2013). In addition, the antioxidant properties of hydroxycinammic acid derivatives, like 3-O-caffeoylquinic acid, are wellknown (Marzouk, Moharram, Haggag, Ibrahim, & Badary, 2006;Ibrahim & Haggag, 2013;Teixeira & Silva, 2013). On the other hand, the best antiradical scavenger against O 2 •-and NO• exhibited by the TCe6 leaf extracts could be associated with the highest amount of kaempferol-3-O-rutinoside.…”