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Matthias Hamburger - One of the best experts on this subject based on the ideXlab platform.
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NMR-Based Metabolomic Study on Isatis tinctoria: Comparison of Different Accessions, Harvesting Dates, and the Effect of Repeated Harvesting.
Journal of natural products, 2015Co-Authors: Niels Guldbrandsen, Sarantos Kostidis, Hartmut Schäfer, Maria De Mieri, Manfred Spraul, Alexios-leandros Skaltsounis, Emmanuel Mikros, Matthias HamburgerAbstract:Isatis tinctoria is an ancient dye and medicinal plant with potent anti-inflammatory and antiallergic properties. Metabolic differences were investigated by NMR spectroscopy of accessions from different origins that were grown under identical conditions on experimental plots. For these accessions, metabolite profiles at different harvesting dates were analyzed, and single and repeatedly harvested plants were compared. Leaf samples were shock-frozen in liquid N2 immediately after being harvested, freeze-dried, and cryomilled prior to extraction. Extracts were prepared by pressurized liquid extraction with ethyl acetate and 70% aqueous methanol. NMR spectra were analyzed using a combination of different methods of multivariate data analysis such as principal component analysis (PCA), canonical analysis (CA), and k-nearest neighbor concept (k-NN). Accessions and harvesting dates were well separated in the PCA/CA/k-NN analysis in both extracts. Pairwise statistical total correlation spectroscopy (STOCSY) reve...
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NMR-Based Metabolomic Study on Isatis tinctoria: Comparison of Different Accessions, Harvesting Dates, and the Effect of Repeated Harvesting
2015Co-Authors: Niels Guldbrandsen, Sarantos Kostidis, Maria De Mieri, Manfred Spraul, Alexios-leandros Skaltsounis, Emmanuel Mikros, Hartmut Schäfer, Matthias HamburgerAbstract:Isatis tinctoria is an ancient dye and medicinal plant with potent anti-inflammatory and antiallergic properties. Metabolic differences were investigated by NMR spectroscopy of accessions from different origins that were grown under identical conditions on experimental plots. For these accessions, metabolite profiles at different harvesting dates were analyzed, and single and repeatedly harvested plants were compared. Leaf samples were shock-frozen in liquid N2 immediately after being harvested, freeze-dried, and cryomilled prior to extraction. Extracts were prepared by pressurized liquid extraction with ethyl acetate and 70% aqueous methanol. NMR spectra were analyzed using a combination of different methods of multivariate data analysis such as principal component analysis (PCA), canonical analysis (CA), and k-nearest neighbor concept (k-NN). Accessions and harvesting dates were well separated in the PCA/CA/k-NN analysis in both extracts. Pairwise statistical total correlation spectroscopy (STOCSY) revealed unsaturated fatty acids, porphyrins, carbohydrates, indole derivatives, isoprenoids, phenylpropanoids, and minor aromatic compounds as the cause of these differences. In addition, the metabolite profile was affected by the repeated harvest regime, causing a decrease of 1,5-anhydroglucitol, sucrose, unsaturated fatty acids, porphyrins, isoprenoids, and a flavonoid
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Metabolomic studies on Isatis tinctoria - Comparison of different origins, harvesting dates, and the effect of repeated harvesting
Planta Medica, 2013Co-Authors: Niels Guldbrandsen, Sarantos Kostidis, Alexios-leandros Skaltsounis, Emmanuel Mikros, Matthias HamburgerAbstract:Isatis tinctoria (Brassicaceae) is an ancient dye and medicinal plant with potent anti-inflammatory and anti-allergic properties [1]. We investigated metabolic differences by NMR spectroscopy of plants grown under identical conditions on experimental plots at the Agricultural Field Station of Thuringia in Dornburg, Germany. Comparisons were carried out for plants of different geographic origins, different harvesting dates, and between single and repeatedly harvested plants. For the study, plants of six origins were compared, and they were harvested at six time points. In addition, the effect of repeated harvesting was investigated. Leaf samples were shock-frozen with liquid N2 immediately after harvest, freeze-dried, and cryomilled prior to extraction. Extracts were prepared by pressurized liquid extraction (PLE) with 70% aqueous methanol. The spectra were analyzed by multivariate data analysis. The score plots produced by principal component analysis (PCA) revealed differences in the metabolic profile between the harvesting dates. The loading plots showed that the spectral region of carbohydrate resonances was responsible for these differences. In contrast, no major differences were seen in the metabolites of different origins. Partial least square discriminant analysis (PLS-DA) revealed no effect of repeated harvesting on the metabolic profiles. Reference: [1] Hamburger M., Phytochemistry Reviews, 1, 333 – 344 (2002)
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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.
Salvatore Ragusa - One of the best experts on this subject based on the ideXlab platform.
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Volatile Constituents in Dried Roots of Isatis tinctoria L. (Brassicaceae)
Journal of Essential Oil Research, 2010Co-Authors: Antonella Verzera, Cettina Condurso, M. Ziino, Giovanna Dima, Salvatore RagusaAbstract:Abstract The root volatile constituents of Isatis tinctoria L. (Brassicaceae) have been studied by GC-FID, and solid-phase microextraction and gas chromatography/mass spectrometry (SPME-GC/MS). Thirty components were fully characterized by mass spectra, linear retention indices, and injection of standards; the average composition (ppm) as single components and classes of substances is reported. The root volatiles in I. tinctoria were characterized by a high amount of 3-butenyl isothiocyanate, which accounted for about 82% of the total volatile fraction.
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the leaf volatile constituents of Isatis tinctoria by solid phase microextraction and gas chromatography mass spectrometry
Planta Medica, 2006Co-Authors: Cettina Condurso, Antonella Verzera, V. Romeo, M. Ziino, Alessandra Trozzi, Salvatore RagusaAbstract:The leaf volatile constituents of Isatis tinctoria L. (Brassicaceae) have been studied by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry (SPME/GC-MS). Seventy components were fully characterized by mass spectra, linear retention indices, and injection of standards; the average composition (ppm) as single components and classes of substances is reported. Aliphatic hydrocarbons, acids, alcohols, aldehydes and esters, aromatic aldehydes, esters and ethers, furans, isothiocyanates and thiocyanates, sulfurated compounds, nitriles, terpenes and sesquiterpenes were identified. Leaf volatiles in Isatis tinctoria L. were characterized by a high amount of isothiocyanates which accounted for about 40 % of the total volatile fraction. Isothiocyanates are important and characteristic flavour compounds in Brassica vegetables and the cancer chemo-protective attributes are recently responsible for their growing interest.
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The leaf volatile constituents of Isatis tinctoria by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry.
Planta medica, 2006Co-Authors: Cettina Condurso, Antonella Verzera, V. Romeo, M. Ziino, Alessandra Trozzi, Salvatore RagusaAbstract:The leaf volatile constituents of Isatis tinctoria L. (Brassicaceae) have been studied by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry (SPME/GC-MS). Seventy components were fully characterized by mass spectra, linear retention indices, and injection of standards; the average composition (ppm) as single components and classes of substances is reported. Aliphatic hydrocarbons, acids, alcohols, aldehydes and esters, aromatic aldehydes, esters and ethers, furans, isothiocyanates and thiocyanates, sulfurated compounds, nitriles, terpenes and sesquiterpenes were identified. Leaf volatiles in Isatis tinctoria L. were characterized by a high amount of isothiocyanates which accounted for about 40 % of the total volatile fraction. Isothiocyanates are important and characteristic flavour compounds in Brassica vegetables and the cancer chemo-protective attributes are recently responsible for their growing interest.
Cettina Condurso - One of the best experts on this subject based on the ideXlab platform.
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Volatile Constituents in Dried Roots of Isatis tinctoria L. (Brassicaceae)
Journal of Essential Oil Research, 2010Co-Authors: Antonella Verzera, Cettina Condurso, M. Ziino, Giovanna Dima, Salvatore RagusaAbstract:Abstract The root volatile constituents of Isatis tinctoria L. (Brassicaceae) have been studied by GC-FID, and solid-phase microextraction and gas chromatography/mass spectrometry (SPME-GC/MS). Thirty components were fully characterized by mass spectra, linear retention indices, and injection of standards; the average composition (ppm) as single components and classes of substances is reported. The root volatiles in I. tinctoria were characterized by a high amount of 3-butenyl isothiocyanate, which accounted for about 82% of the total volatile fraction.
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the leaf volatile constituents of Isatis tinctoria by solid phase microextraction and gas chromatography mass spectrometry
Planta Medica, 2006Co-Authors: Cettina Condurso, Antonella Verzera, V. Romeo, M. Ziino, Alessandra Trozzi, Salvatore RagusaAbstract:The leaf volatile constituents of Isatis tinctoria L. (Brassicaceae) have been studied by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry (SPME/GC-MS). Seventy components were fully characterized by mass spectra, linear retention indices, and injection of standards; the average composition (ppm) as single components and classes of substances is reported. Aliphatic hydrocarbons, acids, alcohols, aldehydes and esters, aromatic aldehydes, esters and ethers, furans, isothiocyanates and thiocyanates, sulfurated compounds, nitriles, terpenes and sesquiterpenes were identified. Leaf volatiles in Isatis tinctoria L. were characterized by a high amount of isothiocyanates which accounted for about 40 % of the total volatile fraction. Isothiocyanates are important and characteristic flavour compounds in Brassica vegetables and the cancer chemo-protective attributes are recently responsible for their growing interest.
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The leaf volatile constituents of Isatis tinctoria by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry.
Planta medica, 2006Co-Authors: Cettina Condurso, Antonella Verzera, V. Romeo, M. Ziino, Alessandra Trozzi, Salvatore RagusaAbstract:The leaf volatile constituents of Isatis tinctoria L. (Brassicaceae) have been studied by Solid-Phase Microextraction and Gas chromatography/Mass Spectrometry (SPME/GC-MS). Seventy components were fully characterized by mass spectra, linear retention indices, and injection of standards; the average composition (ppm) as single components and classes of substances is reported. Aliphatic hydrocarbons, acids, alcohols, aldehydes and esters, aromatic aldehydes, esters and ethers, furans, isothiocyanates and thiocyanates, sulfurated compounds, nitriles, terpenes and sesquiterpenes were identified. Leaf volatiles in Isatis tinctoria L. were characterized by a high amount of isothiocyanates which accounted for about 40 % of the total volatile fraction. Isothiocyanates are important and characteristic flavour compounds in Brassica vegetables and the cancer chemo-protective attributes are recently responsible for their growing interest.
Christine Oberthür - One of the best experts on this subject based on the ideXlab platform.
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flavone c glycosides from Isatis tinctoria leaves
Heterocycles, 2005Co-Authors: Yongxian Cheng, Christine Oberthür, Bernd Schneider, Heidemarie Graf, Sven Adler, Matthias HamburgerAbstract:Two new flavone C-glycosides, chrysoeriol 6-C-β-D-glucopyranosyl-(1→3)-β-glucopyranoside (1) and apigenin 6-C-β-D-glucopyranosyl-(1→3)-β-glucopyranoside (2) were isolated from a methanolic extract of Isatis tinctoria leaves and identified on the basis of spectral analysis and hydrolysis. Two known flavone C-glycosides, isoscoparin (3) and isovitexin (4), were also identified.
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the content of indigo precursors in Isatis tinctoria leaves a comparative study of selected accessions and post harvest treatments
Phytochemistry, 2004Co-Authors: Christine Oberthür, Matthias Hamburger, Heidemarie GrafAbstract:We recently clarified the nature of indigo precursors in woad (Isatis tinctoria L.), by identifying the major indoxyl glycoside as isatan A (indoxyl-3-O-(6'-O-malonyl-beta-D-ribohexo-3-ulopyranoside)), and by correcting the structure of the related isatan B (indoxyl-3-O-beta-D-ribohexo-3-ulopyranoside). A quantitative densitometric assay for isatans A and B, and indican, was established and validated. HPTLC separation on silica gel was followed by densitometric analysis of indigoid pigments formed after treatment with dilute acid or base. The seasonal variation of indoxyl glycosides in woad leaves was investigated with first-year plants (rosette stage) of five defined I. tinctoria L. and one I. indigotica L. accessions. Isatan A content reached up to 7.6% of dry weight in I. tinctoria, and up to 21.8% in I. indigotica. The influence of various post-harvest treatments was studied. High concentrations of isatans A and B were found in freeze-dried leaf samples, whereas the content of indican was lowest. Conventional drying at ambient or 40 degrees C led to complete disappearance of isatans A and B. The concentration of indican, in contrast, was 3- to 5-fold higher in leaf samples submitted to drying at ambient and 40 degrees C, respectively.
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Tryptanthrin content in Isatis tinctoria leaves--a comparative study of selected strains and post-harvest treatments.
Planta medica, 2004Co-Authors: Christine Oberthür, Matthias HamburgerAbstract:Tryptanthrin is a pharmacologically active compound in the anti-inflammatory herb Isatis tinctoria, with potent inhibitory activity on prostaglandin and leukotriene synthesis and on inducible NO synthase. The tryptanthrin content of five defined woad strains was analyzed in dependence of the time of harvest and post-harvest treatment. Tryptanthrin was determined by a validated ESI-LC-MS isotope dilution assay with d(8)-tryptanthrin as internal standard. The tryptanthrin concentration in freeze-dried leaf samples was low. Drying at ambient temperature led to a significant increase of tryptanthrin concentration, but the highest concentrations were found when leaves were dried at 40 degrees C. Tryptanthrin content in fermented woad leaves was below the limit of quantification. Tryptanthrin appears thus to be a product of post-harvest processes, but details of its formation remain to be elucidated.
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the elusive indigo precursors in woad Isatis tinctoria l identification of the major indigo precursor isatan a and a structure revision of isatan b
Chemistry & Biodiversity, 2004Co-Authors: Christine Oberthür, Bernd Schneider, Heidemarie Graf, Matthias HamburgerAbstract:A metabolite-profiling study of shock-frozen leaves of Isatis tinctoria L., an old indigo dye plant and medicinal herb, revealed a complex pattern of indigo-forming compounds with higher polarities than the known indigo precursors isatan B and indican. These highly unstable compounds underwent rapid post-harvest transformation and were not detected in air-dried leaves. The major indigo precursor, named isatan A (4), was isolated by rapid normal-phase and gel chromatography, along with isatan B (3). A full spectral data set of 3 showed that the previous structure assignment as 'indoxyl-5-ketogluconate' has to be revised to 1H-indol-3-yl beta-D-ribohex-3-ulopyranoside. Isatan A (4) was identified as 1H-indol-3-yl 6'-O-(carboxyacetyl)-beta-D-ribohex-3'-ulopyranoside. In aqueous solution, glycosides 3 and 4 occur as hydrates and undergo rapid hydrolysis under very mild acidic or basic conditions.
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The content of indigo precursors in Isatis tinctoria leaves — a comparative study of selected accessions and post-harvest treatments
Phytochemistry, 2004Co-Authors: Christine Oberthür, Heidemarie Graf, Matthias HamburgerAbstract:We recently clarified the nature of indigo precursors in woad (Isatis tinctoria L.), by identifying the major indoxyl glycoside as isatan A (indoxyl-3-O-(6'-O-malonyl-beta-D-ribohexo-3-ulopyranoside)), and by correcting the structure of the related isatan B (indoxyl-3-O-beta-D-ribohexo-3-ulopyranoside). A quantitative densitometric assay for isatans A and B, and indican, was established and validated. HPTLC separation on silica gel was followed by densitometric analysis of indigoid pigments formed after treatment with dilute acid or base. The seasonal variation of indoxyl glycosides in woad leaves was investigated with first-year plants (rosette stage) of five defined I. tinctoria L. and one I. indigotica L. accessions. Isatan A content reached up to 7.6% of dry weight in I. tinctoria, and up to 21.8% in I. indigotica. The influence of various post-harvest treatments was studied. High concentrations of isatans A and B were found in freeze-dried leaf samples, whereas the content of indican was lowest. Conventional drying at ambient or 40 degrees C led to complete disappearance of isatans A and B. The concentration of indican, in contrast, was 3- to 5-fold higher in leaf samples submitted to drying at ambient and 40 degrees C, respectively.
Sabrina Tozzi - One of the best experts on this subject based on the ideXlab platform.
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Seasonal variation of indigo precursors in Isatis tinctoria L. and Polygonum tinctorium Ait. as affected by water deficit
Environmental and Experimental Botany, 2006Co-Authors: Elisabetta Campeol, Sabrina Tozzi, Luciana G. Angelini, Marcello BertolacciAbstract:In order to identify new crops suitable for indigo production in Italy, seasonal variation in productivity of indigo precursors was studied in woad (Isatis tinctoria L., Family Cruciferae) and in dyer’s knotweed (Polygonum tinctorium Ait., Family Polygonaceae), grown in central Italy under temperate climate. Indigo precursors, indoxyl-3-ketogluconate (isatan B) and indoxyl-β-D-glucoside (indican), were measured in leaves by HPLC analysis under well watered versus rain fed field conditions, and the amount of indigo derived by stoichiometric calculations. Woad showed lower indigo potential than dyer’s knotweed, evaluated as either amount of indigo either per leaf weight or per plant. However, in water stress conditions, woad appeared to be drought tolerant as opposed to dyer’s knotweed revealed very sensitive. In fact, in dyer’s knotweed leaf yield was over 50% reduced in water stress field conditions, characterizing central and southern Italy during July and August, as compared to some 30% in woad. Dyer’s knotweed appears to be more productive, providing water is supplied appropriately, thus making proper irrigation plans necessary to achieve sustainable high yields
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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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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:Abstract 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 β-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°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 fa...
