Flavonoids and their glycosides, including anthocyanins

Purification, characterization and anti-proliferation activities of polysaccharides extracted from Viscum coloratum (Kom.) Nakai.

BackgroundDiarylheptanoids isolated from Curcuma comosa Roxb. have been recently identified as phyto estrogens. However, the mechanism underlying their actions has not yet been identified.Objective...

Diarylheptanoid Phytoestrogens Isolated from the Medicinal Plant Curcuma Comosa: Biologic Actions in Vitro and in Vivo Indicate Estrogen Receptor-Dependent Mechanisms

Diarylheptanoids, natural products with a 1,7-diphenylheptane structural skeleton, are mainly distributed in the roots, rhizomes and bark of Alpinia, Zingiber, Curcuma and Alnus species They have become of interest in natural product research over the past twenty years because of their remarkable anti-cancer, anti-emetic, estrogenic, anti-microbial and anti-oxidant activity This paper compiles all 307 naturally occurring diarylheptanoids from 46 plants as reported in 137 references with their distributions, physiological activities and 13C-NMR spectral data

https://journals.sagepub.com/doi/pdf/10.1177/1934578X1000501035

Naturally occurring diarylheptanoids.

Recently, considerable scientific and therapeutic interest has focused on the structure and functions of the flavonoids. In a previous study, we suggested that hydroxyl (OH) substitutions on specific carbons in the skeleton of the flavonoids might significantly affect their apoptosis-modulating properties. Here, to investigate the effect of various OH substitutions on their diphenylpropane (C6C3C6) skeleton carbons, we selected 10 different flavonoids and assessed their role on UV-induced apoptosis of human keratinocytes, the principal cell type of epidermis. The results showed that 5,7,3',4'-tetrahydroxylflavanone (eriodictyol) and 3,4'-dihydroxy flavone (3,4'-DHF) had a positive effect on cell proliferation of human HaCaT keratinocytes. Treatment with eriodictyol in particular resulted in significant suppression of cell death induced by ultraviolet (UV) light, a major skin-damaging agent. We found that eriodictyol treatment apparently reduced the percentage of apoptotic cells and the cleavage of poly(ADP-ribose) polymerase, concomitant with the repression of caspase-3 activation and reactive oxygen species (ROS) generation. The anti-apoptotic and anti-oxidant effects of eriodictyol were also confirmed in UV-induced cell death of normal human epidermal keratinocyte (NHEK) cells. Taken together, these findings suggest that eriodictyol can be used to protect keratinocytes from UV-induced damage, implying the presence of a complex structure-activity relationship (SAR) in the differential apoptosis-modulating activities of various flavonoids.

The anti-apoptotic and anti-oxidant effect of eriodictyol on UV-induced apoptosis in keratinocytes.

Two new flavanone glucosides, (2S)-homoeriodictyol 7,4′-di-O-β-D-glucopyranoside (4) and (2R)-eriodictyol 7,4′-di-O-β-D-glucopyranoside (5) were isolated from the branches and leaves of Viscum coloratum (KOMAR) NAKAI (Loranthaceae), along with three known flavanone glucosides: (2S)-homoeriodictyol 7-O-β-D-glucopyranoside (1), (2S)-eriodictyol 7-O-β-D-glucopyranoside (2), and (2S)-naringenin 7-O-β-D-glucopyranoside (3). The structures of these compounds were elucidated using spectroscopic methods. The antioxidant activities of these isolated compounds were evaluated by colorimetric methods based on their scavenging effects on hydroxyl radicals and superoxide anion radicals, respectively. All the compounds showed potent albeit varied degrees of antioxidative activities and the structure–activity relationship is discussed.

https://www.jstage.jst.go.jp/article/cpb/54/1/54_1_133/_pdf

Antioxidative Flavanone Glycosides from the Branches and Leaves of Viscum coloratum

Mistletonone, a novel diarylheptanoid, was isolated from the branches and leaves of Viscum coloratum (Kom.) Nakai (Loranthaceae). It was identified as 1,7-di-(p-hydroxyphenyl)-5-hydroxyl-cis-2,3-epoxy-1-one on the basis of spectral evidence. The compound showed significant scavenging effects on hydroxyl radicals and superoxide anion radicals in the direct assay using the electron spin resonance (ESR) technique.

/pdf/mistletonone-a-novel-antioxidative-diarylheptanoid-from-the-3pgonpgz40.pdf

Hui Yao

Papers

Antioxidative Flavanone Glycosides from the Branches and Leaves of Viscum coloratum

Mistletonone, a Novel Antioxidative Diarylheptanoid from the Branches and Leaves of Viscum coloratum