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Matthias Hamburger - One of the best experts on this subject based on the ideXlab platform.
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A comprehensive metabolite profiling of Isatis tinctoria leaf extracts
Phytochemistry, 2009Co-Authors: Tobias Mohn, Inken Plitzko, Matthias HamburgerAbstract:A broad-based characterisation of a pharmacologically active dichloromethane extract from Isatis tinctoria leaves was carried out. For a comprehensive picture we also included the polar constituents of I. tinctoria (MeOH extract) and for comparative purposes, the taxonomically closely related plant I. indigotica. Diode array detector, evaporative light scattering detector, atmospheric pressure chemical ionisation and electrospray ionisation mass spectrometry, and electrospray ionisation time-of-flight mass spectrometry detectors were used in parallel to ensure a wide coverage of secondary metabolites with highly diverging analytical properties. Off-line microprobe nuclear magnetic resonance spectroscopy after peak purification by semi-preparative high-pressure liquid chromatography served for structure elucidation of some minor constituents. More than 65 compounds belonging to various structural classes such as alkaloids, flavonoids, fatty acids, porphyrins, lignans, carotenoids, glucosinolates and cyclohexenones were unambiguously identified, and tentative structures were proposed for additional compounds. Numerous compounds were identified for the first time in the genus Isatis, and an indolic alkaloid was discovered.
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Glucosinolate pattern in Isatis tinctoria and I. indigotica seeds.
Planta Medica, 2008Co-Authors: Tobias Mohn, Matthias HamburgerAbstract:The glucosinolate patterns in seeds of five Isatis TINCTORIA and two Isatis INDIGOTICA accessions were assessed with a recently developed and validated LC-MS assay for direct analysis of glucosinolates without prior desulfatation. Glucosinolate peaks were identified with in-source fragmentation and detection of the sulfate anion ( M/Z = 97), and by MS/MS experiments. The glucosinolate patterns of the seeds showed characteristic differences compared to leaves. GlucoIsatisin and epiglucoIsatisin were diagnostic of seed samples. Qualitative and quantitative differences in glucosinolate patterns between both Isatis species were found for seed samples, enabling a differentiation of the two medicinal plants at the level of seed material.
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Seasonal changes and effect of harvest on glucosinolates in Isatis leaves.
Planta medica, 2008Co-Authors: Tobias Mohn, Kathrin Suter, Matthias HamburgerAbstract:The seasonal fluctuation of glucosinolates in five defined Isatis tinctoria and one Isatis indigotica accessions (first year, rosette stage), grown on field plots under identical conditions, was investigated. Analysis of the intact glucosinolates was carried out with shock frozen, freeze dried leaf samples using a recently developed and validated PLE (pressurized liquid extraction) protocol and ion-pair HPLC coupled with ESI-MS in the negative mode. When comparing the two Isatis species, significant qualitative and quantitative differences in the glucosinolate patterns were observed. Differences among the various Isatis tinctoria accessions were much smaller. We studied the effects of repeated harvesting during the growth season on glucosinolate concentrations and found that repeated harvest did not have a major effect on glucosinolate concentrations of newly grown leaves. Glucosinolates could not be detected in woad leaves submitted to conventional drying.
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Anti-arthritic activity of a lipophilic woad (Isatis tinctoria) extract.
Planta medica, 2006Co-Authors: María-carmen Recio, Matthias Hamburger, Miguel Cerdá-nicolás, José-luis RíosAbstract:A dichloromethane extract of Isatis tinctoria was tested in the adjuvant-induced arthritis model in rats. The extract (150 mg/kg p. o.) leads to a significant reduction of paw oedema. Radiographic, histological and clinical assessment confirmed reduced damage of cartilage and signs of inflammatory response in comparison to untreated control. No significant differences were observed in the tissular levels of cyclooxygenases 1 and -2, and of inducible nitric oxide synthase in Isatis treated and untreated animals. High dose treatment with Isatis extract for two weeks did not result in macroscopic lesions of the gastric mucosa.
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A comparative study on the skin penetration of pure tryptanthrin and tryptanthrin in Isatis tinctoria extract by dermal microdialysis coupled with isotope dilution ESI-LC-MS.
Planta medica, 2003Co-Authors: Christine Oberthür, Christian Heinemann, Peter Elsner, Eva Benfeldt, Matthias HamburgerAbstract:The indolo[2,1- b]quinazoline alkaloid tryptanthrin has recently been identified as a pharmacologically active compound in Isatis tinctoria, with potent dual inhibitory activity on prostaglandin and leukotriene synthesis. To investigate the skin penetration of tryptanthrin from solutions of pure compound and Isatis extracts, we developed and validated a cutaneous microdialysis model using ex vivo pig foreleg. Microdialysis was performed by placing linear probes in the dermis of the skin in situ, and tryptanthrin concentrations in the dialysates were determined by isotope dilution electrospray ionization LC-MS in the selected ion mode. Measurable concentrations of tryptanthrin were detected 30 min after application. A dose-dependent increase in tryptanthrin concentrations in the dialysate was observed for the Isatis extracts, but not for pure tryptanthrin. Microscopic analysis showed that the pure compound crystallized from the solution but remained in an amorphous state in the extracts.
Tobias Mohn - One of the best experts on this subject based on the ideXlab platform.
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A comprehensive metabolite profiling of Isatis tinctoria leaf extracts
Phytochemistry, 2009Co-Authors: Tobias Mohn, Inken Plitzko, Matthias HamburgerAbstract:A broad-based characterisation of a pharmacologically active dichloromethane extract from Isatis tinctoria leaves was carried out. For a comprehensive picture we also included the polar constituents of I. tinctoria (MeOH extract) and for comparative purposes, the taxonomically closely related plant I. indigotica. Diode array detector, evaporative light scattering detector, atmospheric pressure chemical ionisation and electrospray ionisation mass spectrometry, and electrospray ionisation time-of-flight mass spectrometry detectors were used in parallel to ensure a wide coverage of secondary metabolites with highly diverging analytical properties. Off-line microprobe nuclear magnetic resonance spectroscopy after peak purification by semi-preparative high-pressure liquid chromatography served for structure elucidation of some minor constituents. More than 65 compounds belonging to various structural classes such as alkaloids, flavonoids, fatty acids, porphyrins, lignans, carotenoids, glucosinolates and cyclohexenones were unambiguously identified, and tentative structures were proposed for additional compounds. Numerous compounds were identified for the first time in the genus Isatis, and an indolic alkaloid was discovered.
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Glucosinolate pattern in Isatis tinctoria and I. indigotica seeds.
Planta Medica, 2008Co-Authors: Tobias Mohn, Matthias HamburgerAbstract:The glucosinolate patterns in seeds of five Isatis TINCTORIA and two Isatis INDIGOTICA accessions were assessed with a recently developed and validated LC-MS assay for direct analysis of glucosinolates without prior desulfatation. Glucosinolate peaks were identified with in-source fragmentation and detection of the sulfate anion ( M/Z = 97), and by MS/MS experiments. The glucosinolate patterns of the seeds showed characteristic differences compared to leaves. GlucoIsatisin and epiglucoIsatisin were diagnostic of seed samples. Qualitative and quantitative differences in glucosinolate patterns between both Isatis species were found for seed samples, enabling a differentiation of the two medicinal plants at the level of seed material.
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Seasonal changes and effect of harvest on glucosinolates in Isatis leaves.
Planta medica, 2008Co-Authors: Tobias Mohn, Kathrin Suter, Matthias HamburgerAbstract:The seasonal fluctuation of glucosinolates in five defined Isatis tinctoria and one Isatis indigotica accessions (first year, rosette stage), grown on field plots under identical conditions, was investigated. Analysis of the intact glucosinolates was carried out with shock frozen, freeze dried leaf samples using a recently developed and validated PLE (pressurized liquid extraction) protocol and ion-pair HPLC coupled with ESI-MS in the negative mode. When comparing the two Isatis species, significant qualitative and quantitative differences in the glucosinolate patterns were observed. Differences among the various Isatis tinctoria accessions were much smaller. We studied the effects of repeated harvesting during the growth season on glucosinolate concentrations and found that repeated harvest did not have a major effect on glucosinolate concentrations of newly grown leaves. Glucosinolates could not be detected in woad leaves submitted to conventional drying.
Sabrina Tozzi - One of the best experts on this subject based on the ideXlab platform.
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Light quality influences indigo precursors production and seed germination in Isatis tinctoria L. and Isatis indigotica Fort.
Photochemistry and photobiology, 2005Co-Authors: Sabrina Tozzi, Bartolomeo Lercari, Luciana Gabriella AngeliniAbstract:Isatis tinctoria L. and Isatis indigotica Fort. are biennial herbaceous plants belonging to the family of Cruciferae that are used as a source of natural indigo and show several morphological and genetic differences. Production of indigo (indigotin) precursors, indican (indoxyl beta-D glucoside) and isatan B (indoxyl ketogluconate), together with seed germination ability were compared in Isatis tinctoria and Isatis indigotica grown under six different light conditions (darkness, white, red, far red, blue, yellow light) at 25 degrees C. Light quality influenced both germination and production of indigo precursors in the two Isatis species. Different responsiveness to far red and blue light was observed. Indeed, a detrimental effect on germination by blue and far red light was found in I. tinctoria only. Different amounts of isatan B were produced under red and far red light in the two Isatis species. In I. tinctoria, the level of main indigo precursor isatan B was maximal under red light and minimal under far red light. Whereas in I. indigotica far red light promoted a large accumulation of isatan B. The photon fluence rate dependency for white and yellow light responses showed that the accumulation of indigo precursors was differently influenced in the two Isatis species. In particular, both white and yellow light enhanced above 40 micromol m(-2) s(-1) the production of isatan B in I. indigotica while only white light showed a photon fluence dependency in I. tinctoria. These results suggest a different role played by the labile and stable phytochrome species (phyA and phyB) in the isatan B production in I. tinctoria and I. indigotica. I. indigotica, whose germination percentage was not influenced by light quality, demonstrated higher germination capability compared with I. tinctoria. In fact, I. tinctoria showed high frequency of germination in darkness and under light sources that establish high phytochrome photoequilibrium (red, white and yellow light). Germination in I. tinctoria was negatively affected by far red and blue light. I. indigotica seeds appear to be indifferent to canopy-like light (far red). Our results provide further insights on the distinct behaviour of I. tinctoria and I. indigotica that belong to two different genetic clusters and different original environments.
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Quantitative Analysis of Indigo and Indigo Precursors in Leaves of Isatis spp. and Polygonum tinctorium
Biotechnology progress, 2004Co-Authors: Kg Gilbert, Hamish G. Maule, Bernd Rudolph, Mervyn Lewis, Harold J. Vandenburg, Ester Sales, Sabrina Tozzi, David T. CookeAbstract:Analysis of extracts from two woad species (Isatis tinctoria and Isatis indigotica) and Polygonum tinctorium revealed that only one indigo precursor (indican) was present in Polygonum, but two precursors were found in Isatis spp. This was done using high performance liquid chromatography (HPLC), coupled to an evaporative light scattering detector (ELSD). In Isatis spp., the indigo precursors indican and a fraction representing isatan B were identified. The proportion of indican and isatan B was different between the two Isatis spp. tested. For the first time, it was possible to quantify the precursors in woad plant species, and the results were found to be in good agreement with those made from total indigo quantification using two different spectrophotometric methods or a derivatization technique.
José-luis Ríos - One of the best experts on this subject based on the ideXlab platform.
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Anti-arthritic activity of a lipophilic woad (Isatis tinctoria) extract.
Planta medica, 2006Co-Authors: María-carmen Recio, Matthias Hamburger, Miguel Cerdá-nicolás, José-luis RíosAbstract:A dichloromethane extract of Isatis tinctoria was tested in the adjuvant-induced arthritis model in rats. The extract (150 mg/kg p. o.) leads to a significant reduction of paw oedema. Radiographic, histological and clinical assessment confirmed reduced damage of cartilage and signs of inflammatory response in comparison to untreated control. No significant differences were observed in the tissular levels of cyclooxygenases 1 and -2, and of inducible nitric oxide synthase in Isatis treated and untreated animals. High dose treatment with Isatis extract for two weeks did not result in macroscopic lesions of the gastric mucosa.
Luciana Gabriella Angelini - One of the best experts on this subject based on the ideXlab platform.
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Light quality influences indigo precursors production and seed germination in Isatis tinctoria L. and Isatis indigotica Fort.
Photochemistry and photobiology, 2005Co-Authors: Sabrina Tozzi, Bartolomeo Lercari, Luciana Gabriella AngeliniAbstract:Isatis tinctoria L. and Isatis indigotica Fort. are biennial herbaceous plants belonging to the family of Cruciferae that are used as a source of natural indigo and show several morphological and genetic differences. Production of indigo (indigotin) precursors, indican (indoxyl beta-D glucoside) and isatan B (indoxyl ketogluconate), together with seed germination ability were compared in Isatis tinctoria and Isatis indigotica grown under six different light conditions (darkness, white, red, far red, blue, yellow light) at 25 degrees C. Light quality influenced both germination and production of indigo precursors in the two Isatis species. Different responsiveness to far red and blue light was observed. Indeed, a detrimental effect on germination by blue and far red light was found in I. tinctoria only. Different amounts of isatan B were produced under red and far red light in the two Isatis species. In I. tinctoria, the level of main indigo precursor isatan B was maximal under red light and minimal under far red light. Whereas in I. indigotica far red light promoted a large accumulation of isatan B. The photon fluence rate dependency for white and yellow light responses showed that the accumulation of indigo precursors was differently influenced in the two Isatis species. In particular, both white and yellow light enhanced above 40 micromol m(-2) s(-1) the production of isatan B in I. indigotica while only white light showed a photon fluence dependency in I. tinctoria. These results suggest a different role played by the labile and stable phytochrome species (phyA and phyB) in the isatan B production in I. tinctoria and I. indigotica. I. indigotica, whose germination percentage was not influenced by light quality, demonstrated higher germination capability compared with I. tinctoria. In fact, I. tinctoria showed high frequency of germination in darkness and under light sources that establish high phytochrome photoequilibrium (red, white and yellow light). Germination in I. tinctoria was negatively affected by far red and blue light. I. indigotica seeds appear to be indifferent to canopy-like light (far red). Our results provide further insights on the distinct behaviour of I. tinctoria and I. indigotica that belong to two different genetic clusters and different original environments.
