Using exhaustive chromatographic separation we have isolated (-)-tigloyl-deangeloyl-gomisin F as a novel dibenzocyclooctadiene lignan from schisandra chinensis. With the help of HPLC, we further isolated (+)-schisandrin, (+)-deoxyschisandrin, (+)-γ-schisandrin, (-)-gomisin J, (+)-gomisin A, (-)-gomisin N, (-)-tigloyl-gomisin P, (-)-wuweizisu C, (-)-gomisin D, rubrisandrin A, (-)-gomisin G, (+)-gomisin K (3) and (-)-schisantherin C. A full NMR description of (-)-schisantherin C was carried out with the aim to confirm previous reports of its structure. Compounds isolated were identified on the basis of UV, IR, (1)H- and (13)C-NMR and MS. The cytotoxicity of lignans was tested for the BY-2 cell line alone and as a synergistic effect with the cytotoxic agent camptothecin. Lignans showed various toxicity and synergistic and antagonistic effects on camptothecin-induced cytotoxicity. Cytotoxicity against colon cancer cell line LoVo was also tested.

• MeSH
• apoptóza účinky léků   MeSH
• buněčné linie MeSH
• chemická frakcionace MeSH
• cytotoxiny chemie   izolace a purifikace   toxicita   MeSH
• lidé MeSH
• lignany chemie   izolace a purifikace   toxicita   MeSH
• nádorové buněčné linie MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• proliferace buněk účinky léků   MeSH
• rostlinné extrakty chemie   MeSH
• Schisandra chemie   MeSH
• tabák účinky léků   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The antioxidant properties of pomiferin, isopomiferin, osajin and catalposide are evaluated. The electrochemical behaviour of these compounds at a carbon paste electrode was studied using square wave voltammetry. Oxidative signals, optimized frequencies and appropriate pH acetate buffer conditions were determined. The detection limits (3S/N) for pomiferin, isopomiferin, osajin and catalposide were estimated to be 50 pg/ml, 800 pg/ml, 40 pg/ml and 10 ng/ml, respectively. Furthermore, spectrometric test was employed with 2,2-diphenyl-1-picrylhydrazyle (DPPH) to evaluate the antioxidant activities of these compounds. Based on the obtained results, the highest antioxidant activity measured by DPPH tests was found at pomiferin followed by isopomiferin. The activities of osajin and catalposide were undetectable. The protective effects of pomiferin, isopomiferin, osajin and catalposide on DNA exposed to oxygen radicals in vitro were also studied. Changes in height of oxidative signals for the four bases (guanine, thymine, adenine and cytosine) were measured for DNA exposed to oxygen radicals, generated by Fenton's reaction, non-oxidized ssDNA (50 microg/ml) displayed well developed signals; however, after oxidative damage the observed oxidative signals decreased. Significant protective effects were observed for pomiferin and osajin. Decreased effect was observed for isopomiferin while a further reduced protective effect was seen for DNA exposed to catalposide. Based on the obtained results, pomiferin had the highest antioxidant activity followed by isopomiferin, osajin and catalposide.

• MeSH
• antioxidancia analýza   farmakologie   chemie   MeSH
• benzopyrany MeSH
• elektrochemie MeSH
• financování organizované MeSH
• glukosidy MeSH
• isoflavony analýza   farmakologie   chemie   MeSH
• koncentrace vodíkových iontů MeSH
• molekulární struktura MeSH
• oxidace-redukce účinky léků   MeSH
• spektrofotometrie metody   MeSH
• Publikační typ
• srovnávací studie MeSH

Eight C-6-geranylflavonoids ( 1- 8) were isolated from an ethanol extract of Paulownia tomentosa fruits. Tomentodiplacone ( 1), 3'- O-methyl-5'-hydroxydiplacone ( 2), 3'- O-methyl-5'- O-methyldiplacone ( 3), and tomentodiplacone B ( 4) were obtained as new compounds, and 3'- O-methyldiplacol ( 5) was isolated for the first time from a natural source. The structures of these new compounds were determined by using mass spectrometry (including HRMS) and 1D and 2D NMR spectroscopy, and the absolute configurations of the compounds were determined by circular dichroism. The antibacterial activities of 1- 8 against seven bacteria and yeast were evaluated.

• MeSH
• antibakteriální látky farmakologie   chemie   izolace a purifikace   MeSH
• Bacteria účinky léků   MeSH
• Candida albicans účinky léků   MeSH
• cirkulární dichroismus MeSH
• financování organizované MeSH
• flavonoidy farmakologie   chemie   izolace a purifikace   MeSH
• léčivé rostliny chemie   MeSH
• mikrobiální testy citlivosti MeSH
• molekulární struktura MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• ovoce chemie   MeSH
• Scrophulariaceae chemie   MeSH
• Geografické názvy
• Česká republika MeSH

Paulownia tomentosa is a large indecidous tree planted mostly for its fast growing wood and decorative purposes. The tree is also used in traditional Chinese medicine. As a part of our study of natural polyphenols, the fruits of Paulownia tomentosa were extracted by EtOH and than subjected to liquid/liquid extraction. Fractions were analysed by TLC and HPLC to determine presence of phenolic substances. We identified and quantified acteoside (1) and isoacteoside (2) in the EtOAc and n-BuOH extracts; mimulone (3) and diplacone (4) in the MeOH extract. To determine the antiradical activity of extracts we used the anti DPPH and peroxynitrite assays. The activity was expressed as Trolox C equivalents, IC50 for DPPH scavenging and a time dependency course was established. The polyphenols content was determined; results were expressed as gallic acid equivalents. Using these methods we found the fractions of the n-BuOH, EtOAc and MeOH extracts that display antiradical activity, which could be exploited as potential pharmaceuticals.

• MeSH
• fenoly farmakologie   izolace a purifikace   MeSH
• financování organizované MeSH
• flavonoidy farmakologie   izolace a purifikace   MeSH
• léčivé rostliny MeSH
• léky rostlinné čínské farmakologie   izolace a purifikace   MeSH
• ovoce chemie   MeSH
• rozpouštědla MeSH
• scavengery volných radikálů farmakologie   izolace a purifikace   MeSH
• stromy MeSH

Antioxidant activity of methanolic extracts from inflorescence rachises, corollas, calyxes, leaves, valves of capsules and hypertrophied placenta of Catalpa bignonioides by 1,1-diphenyl-2-picrylhydrazyl reduction (DPPH) and tyrosine nitration inhibition induced by peroxynitrite was tested.

• MeSH
• antioxidancia aplikace a dávkování   farmakologie   chemie   terapeutické užití   MeSH
• bifenylové sloučeniny MeSH
• Bignoniaceae MeSH
• financování organizované MeSH
• fytoterapie MeSH
• květy MeSH
• lidé MeSH
• listy rostlin MeSH
• pikráty chemie   MeSH
• rostlinné extrakty aplikace a dávkování   farmakologie   chemie   terapeutické užití   MeSH
• tyrosin chemie   MeSH
• Check Tag
• lidé MeSH