Marigold (Calendula officinalis L.) is one of the most common and widespread plants used medicinally all over the world. The present study aimed to evaluate the anti-acetylcholinesterase activity of marigold flowers, detect the compounds responsible and perform chemical analysis of marigold commercial products. Analysis of 23 varieties of C. officinalis flowers introduced into Siberia allowed u...

The presence of an α-1,6-glucosaccharide enhances absorption of water-soluble quercetin glycosides, a mixture of quercetin-3-O-β-d-glucoside (Q3G, 31.8%), mono (23.3%), di (20.3%) and more d-glucose adducts with α-1,4-linkage to a d-glucose moiety of Q3G, in a ligated small intestinal loop of anesthetized rats. We prepared α-1,6-glucosaccharides with different degrees of polymerization (DP) enz...

Seven flavonoids have been isolated from the aerial parts of Halostachys caspica C. A. Mey. (Chenopodiaceae) for the first time. By means of physicochemical and spectrometric analysis, they were identified as luteolin (1), chrysin (2), chrysin 7-O-β-D-glucopyranoside (3), quercetin (4), quercetin 3-O-β-D-glucopyranoside (5), isorhamentin-3-O-β-D-glucopyranoside (6), and isorhamentin-3-O-β-D-rut...

A new biflavonol glycoside, quercetin-3-O-β-D-glucopyranoside-(3'→O-3''')-quercetin-3-O-β-D-galactopyranoside (9), together with eight known compounds was isolated for the first time from the leaves of Machilus zuihoensis Hayata (Lauraceae). The structure of compound 9 was elucidated by various types of spectroscopic data analysis. Analysis of the biological activity assay found that compound 9...

In an effort to characterize fruit ripening-related genes functionally, two glucosyltransferases, FaGT6 and FaGT7, were cloned from a strawberry (Fragaria x ananassa) cDNA library and the full-length open reading frames were amplified by rapid amplification of cDNA ends. FaGT6 and FaGT7 were expressed heterologously as fusion proteins in Escherichia coli and target protein was purified using af...

Analogues or isosteres of α,γ-diketoacid (DKA) 1a show potent inhibition of hepatitis C virus (HCV) NS5B polymerase through chelation of the two magnesium ions at the active site. The anti-HCV activity of the flavonoid quercetin (2) could partly be attributed to it being a structural mimic of DKAs. In order to delineate the structural features required for the inhibitory effect and improve the ...

5,7-dihydroxy-3-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]-2-(3,4-dihydroxyphenyl)-4H-1-benzopyran-4-one (quercetin 3-sophorotrioside), a flavonol triglycoside, isolated from Pisum sativum shoots and showing protective effects on liver injury induced by chemicals, was synthesized for the first time. The target compound was successfully synthesized in eig...

China is one of the most important centers of diversity for Eriobotrya japonica Lindl. in the world. In this study, seven loquat cultivars grown in China were evaluated for their phenolic compounds and antioxidant activity. Eleven phenolic compounds, i.e., 3-p-coumaroylquinincacid (3-p-CoQA), 5-caffeoylquinic acid (5-CQA), 4-caffeoylquinic acid (4-CQA), 3-caffeoylquinic acid (3-CQA), 5-feruloyl...

The effects of elevated CO2 concentrations on the antioxidant capacity and flavonoid content in strawberry fruit (Fragaria x ananassa Duch.) were studied under field conditions. Increased CO(2) (300 and 600 micromol mol(-1) above ambient) concentrations resulted in increases in ascorbic acid (AsA), glutathione (GSH), and ratios of AsA to dehydroascorbic acid (DHAsA) and GSH to oxidized glutathi...

two new prenylated flavonoids, named scariosin (1) and isorhynchospermin (2) were isolated from the leaves of paracalyx scariosa together with kaempferol, quercetin, kaempferol 3-o- rutinoside and rutin. the structures of (1) and (2) were characterized as 8-c- prenyl- taxifolin 7,3'-dimethylether and 6-c-prenylquercetin 7,4'-dimethylether by their chemical and spectra data, respectively.