The antioxidant activity of Scorzonera parviflora Jacq. roots were assessed by measuring their ability to scavenge ABTS and DPPH radicals. Bioactivity-guided fractionation was utilized to identify the compound(s) responsible for this activity. The most active phase, ethyl acetate, was isolated using column chromatography. The resulting fractions were then purified using preparative TLC on reverse phase and semi-preparative HPLC. The structures of the pure compounds were elucidated by spectral analysis (MS and 1H, 13C, 2D-NMR). Three undescribed phenolic acid derivatives, namely parvifloric acid A (1), B (2), and C (3), and one new sesquiterpene lactone, parviflorin (4) together with seven known compounds were isolated and identified as scopolin (5), scopoletin (6), caffeic acid (7), protocatechuic acid (8), 4,5-O-dicaffeoylquinic acid (9) 3,5-O-dicaffeoylquinic acid (10), and 3,5-O-dicaffeoylquinic acid methyl ester (11). Finally, the pure compounds obtained were tested to evaluate their antioxidant capacities, using ABTS and DPPH radical scavenging potencies. The highest activity was observed with 3,5-O-dicaffeoylquinic acid (10), followed by its methyl ester.
- Klíčová slova
- Antioxidant activity, Asteraceae, Phenolic acids, Scorzonera parviflora, Sesquiterpene lactone,
- MeSH
- antioxidancia * farmakologie izolace a purifikace chemie MeSH
- fytonutrienty farmakologie izolace a purifikace MeSH
- hydroxybenzoáty * izolace a purifikace farmakologie chemie MeSH
- kořeny rostlin * chemie MeSH
- molekulární struktura MeSH
- Scorzonera * chemie MeSH
- seskviterpeny farmakologie izolace a purifikace chemie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antioxidancia * MeSH
- fytonutrienty MeSH
- hydroxybenzoáty * MeSH
- phenolic acid MeSH Prohlížeč
- seskviterpeny MeSH
Seasonal variations of phenolic compounds, in leaves of Zostera marina L. from the Baltic Sea near Kiel/Germany were investigated. Dominant compounds were mono- and disulfated flavonoids and phenylpropanoic acids, in particular luteolin 7,3'-O-disulfate and diosmetin 7-O-sulfate as well as rosmarinic acid, a dimeric phenylpropanoid. All detected sulfated flavones showed similar seasonal trends: there were two significant concentration peaks in June and November. Moreover, two geographically distinct flavonoid chemotypes were identified based on their respective main flavonoid; one chemotype was characterized by the prevalence of luteolin 7,3'-O-disulfate (German Baltic Sea), and the other by the prevalence of diosmetin 7-O-sulfate (Norwegian North Sea). Furthermore, an undescribed tetrameric phenylpropanoid, 7'',8''-didehydrosalvianolic acid B, was isolated and its structure was established by extensive NMR, MS, and CD experiments. This compound inhibited activity of Na+/K+-ATPase in the micro-molar range without any cytotoxic effects against human cancer and normal cells.
- Klíčová slova
- Seasonality of natural product contents, Sulfated phenolics, Zostera marina, Zosteraceae,
- MeSH
- fenoly chemie MeSH
- listy rostlin MeSH
- roční období MeSH
- Zosteraceae * chemie MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Německo MeSH
- Názvy látek
- fenoly MeSH
Seven previously undescribed sesquiterpene lactones, three known sesquiterpene lactones (ixerin D, 15-p-hydroxyphenylacetyllactucin, and 15-p-hydroxyphenylacetyllactucin-8-sulfate), and two known quinic acid derivatives (3-O-feruloylquinic acid and 3,5-di-O-caffeoylquinic acid) were isolated from Sonchus palustris L. roots. Four formerly undescribed compounds were elucidated to be 3β,14-dihydroxycostunolide-3-O-β-D-glucopyranosyl-(2-O-p-hydroxyphenylacetyl)-14-O-p-hydroxyphenylacetate, 15-p-methoxyphenylacetyllactucin, 15-p-methoxyphenylacetyllactucin-8-sulfate, and 8-p-hydroxyphenylacetyllactucin-15-sulfate. Additionally, three undescribed conjugates of lactucin and a eudesmanolide type sesquiterpenic acid, sonchpalustrin, 4″-O-methylsonchpalustrin, and isosonchpalustrin, were characterized. The structures of the newly discovered natural products were elucidated using 1D and 2D NMR spectroscopy and UHPLC-HRMS. 15-p-Hydroxyphenylacetyllactucin and 15-p-methoxyphenylacetyllactucin showed significant in vitro cytotoxicity against CEM and BJ cells with IC50 values ranging from 3.9 to 9.8 μM. Compounds 3 and 4 showed also strong anti-inflammatory activity in vitro.
- Klíčová slova
- Biological activities, Chemophenetics, Quinic acid derivatives, Schleswig-Holstein, Sesquiterpene lactones, Sonchus palustris,
- MeSH
- antitumorózní látky fytogenní chemie izolace a purifikace farmakologie MeSH
- Asteraceae chemie MeSH
- fytonutrienty chemie izolace a purifikace farmakologie MeSH
- kultivované buňky MeSH
- laktony chemie izolace a purifikace farmakologie MeSH
- léky antitumorózní - screeningové testy MeSH
- lidé MeSH
- proliferace buněk účinky léků MeSH
- seskviterpeny chemie izolace a purifikace farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antitumorózní látky fytogenní MeSH
- fytonutrienty MeSH
- laktony MeSH
- seskviterpeny MeSH
Zosteraphenols, two new tetracyclic diarylheptanoids were isolated from the seagrass Zostera marina. The rotameric equilibrium of the strained tetracyclic structures, involving a diastereomeric minor rotamer with opposite axial chirality, resulted in coalescent NMR spectra. Although the elusive minor rotamer was only characterized with 1H chemical shifts, the excellent agreement between experimental and DFT-calculated chemical shifts of both rotamers unequivocally supported this analysis. Absolute configuration of zosteraphenols was determined by DFT prediction of their ECD spectra.