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Meinhart H. Zenk - One of the best experts on this subject based on the ideXlab platform.
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poppy alkaloid profiling by electrospray tandem mass spectrometry and electrospray ft icr mass spectrometry after ring 13c6 tyramine feeding
Phytochemistry, 2007Co-Authors: Jurgen Schmidt, Toni M. Kutchan, Meinhart H. Zenk, Chotima Boettcher, Christine KuhntAbstract:Papaver alkaloids play a major role in medicine and pharmacy. In this study, [ring-13C6]-tyramine as a biogenetic precursor of these alkaloids was fed to Papaver somniferum seedlings. The alkaloid pattern was elucidated both by direct infusion high-resolution ESI-FT-ICR mass spectrometry and liquid chromatography/electrospray tandem mass spectrometry. Thus, based on this procedure, the structure of about 20 alkaloids displaying an incorporation of the labeled tyramine could be elucidated. These alkaloids belong to different classes, e.g. morphinan, benzylisoquinoline, protoberberine, benzo[c]phenanthridine, phthalide isoquinoline and protopine. The valuable information gained from the alkaloid profile demonstrates that the combination of these two spectrometric methods represents a powerful tool for evaluating biochemical pathways and facilitates the study of the flux of distant precursors into these natural products.
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Biotransformation of thebaine by cell cultures of Papaver somniferum and Mahonia nervosa
Phytochemistry, 1997Co-Authors: Rudolf Wilhelm, Meinhart H. ZenkAbstract:Abstract A Papaver somnifverum cell culture transforms thebaine into tetrahydrothebaine and thebainone while Mahonia nervosa transforms thebaine into oripavine
Gabriella Roda - One of the best experts on this subject based on the ideXlab platform.
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Analysis of fluid extracts obtained from Papaver rhoeas petals contaminated with Papaver bracteatum petals.
Planta medica, 2012Co-Authors: Veniero Gambaro, Paola Minghetti, Sebastiano Arnoldi, Maria Laura Colombo, Lucia Dellʼacqua, Antonella Casiraghi, Katia Guerrini, Fiorenza Farè, Gabriella RodaAbstract:In this paper, we report a case of misidentification of medicinal plants involving dried petals of Papaver rhoeas (red poppy) contaminated with Papaver bracteatum (scarlet poppy) petals. Preliminary TLC analysis indicated the presence of thebaine either in the fluid extracts or in the petals. It was therefore necessary to carry out an accurate botanic examination of the plant material, which revealed contamination of the red poppy petals with scarlet poppy petals. Moreover, to confirm the adulteration, we developed and validated an efficient, reversed-phase ion pair HPLC method for determination of the alkaloids specific for the Papaver species. Six petal batches and five commercial fluid extracts were analyzed. Only one petal batch from Iran contained thebaine and its analogue oripavine while the alkaloids typical for the Papaver bracteatum species were identified in all fluid extracts, meaning that they were all prepared with contaminated petals.
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Analysis of fluid extracts obtained with Papaver rhoeas petals contaminated with Papaver bracteatum petals
'Georg Thieme Verlag KG', 2012Co-Authors: Veniero Gambaro, Paola Minghetti, Sebastiano Arnoldi, Maria Laura Colombo, Antonella Casiraghi, Katia Guerrini, L. Dell’, F. Farè, Gabriella RodaAbstract:In this paper we refer a case of misidentification of medicinal plants involving dried petals of Papaver rhoeas contaminated with Papaver bracteatum petals. Preliminarily, TLC analysis evidenced the presence of thebaine either in the fluid extracts or in the petals. In this frame it was necessary to carry out an accurate botanic examination of the vegetable material which revealed the contamination of the red poppy petals with scarlet poppy petals. Moreover to confirm the adulteration, we developed and validated an efficient reverse phase ion pair HPLC method for the determination of the alkaloids contained in the Papaver species. Six petal batches and five commercial fluid extracts were analysed. Only one petal batch coming from Iran resulted to contain thebaine and its analogue oripavine, while all the fluid extracts contained the alkaloids typical of the Papaver bracteatum species, meaning that they were all prepared with contaminated petals
Toni M. Kutchan - One of the best experts on this subject based on the ideXlab platform.
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poppy alkaloid profiling by electrospray tandem mass spectrometry and electrospray ft icr mass spectrometry after ring 13c6 tyramine feeding
Phytochemistry, 2007Co-Authors: Jurgen Schmidt, Toni M. Kutchan, Meinhart H. Zenk, Chotima Boettcher, Christine KuhntAbstract:Papaver alkaloids play a major role in medicine and pharmacy. In this study, [ring-13C6]-tyramine as a biogenetic precursor of these alkaloids was fed to Papaver somniferum seedlings. The alkaloid pattern was elucidated both by direct infusion high-resolution ESI-FT-ICR mass spectrometry and liquid chromatography/electrospray tandem mass spectrometry. Thus, based on this procedure, the structure of about 20 alkaloids displaying an incorporation of the labeled tyramine could be elucidated. These alkaloids belong to different classes, e.g. morphinan, benzylisoquinoline, protoberberine, benzo[c]phenanthridine, phthalide isoquinoline and protopine. The valuable information gained from the alkaloid profile demonstrates that the combination of these two spectrometric methods represents a powerful tool for evaluating biochemical pathways and facilitates the study of the flux of distant precursors into these natural products.
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molecular characterization of the salutaridinol 7 o acetyltransferase involved in morphine biosynthesis in opium poppy Papaver somniferum
Journal of Biological Chemistry, 2001Co-Authors: Torsten Grothe, Rainer Lenz, Toni M. KutchanAbstract:Salutaridinol 7-O-acetyltransferase (EC ) catalyzes the conversion of the phenanthrene alkaloid salutaridinol to salutaridinol-7-O-acetate, the immediate precursor of thebaine along the morphine biosynthetic pathway. We have isolated a cDNA clone that corresponds to the internal amino acid sequences of the native enzyme purified from a cell suspension culture of opium poppy Papaver somniferum. The recombinant enzyme acetylated the 7-hydroxyl moiety of salutaridinol in the presence of acetyl-CoA. The apparent K(m) value for salutaridinol was determined to be 9 microm and 54 microm for acetyl-CoA. The gene transcript was detected in extracts from Papaver orientale and Papaver bracteatum in addition to P. somniferum. Genomic DNA gel blot analysis indicated that there is likely a single copy of this gene in the P. somniferum genome. The amino acid sequence of salutaridinol 7-O-acetyltransferase is most similar (37% identity) to that of deacetylvindoline acetyltransferase of Catharanthus roseus. Salutaridinol 7-O-acetyltransferase is the second enzyme specific to morphine biosynthesis for which we have isolated a cDNA. Taken together with the other cDNAs cloned encoding norcoclaurine 6-O-methyltransferase, (S)-N-methylcoclaurine 3'-hydroxylase, the cytochrome P-450 reductase, and codeinone reductase, significant progress has been made toward accumulating genes of this pathway to enable the end goal of a biotechnological production of morphinan alkaloids.
Blanca B. Landa - One of the best experts on this subject based on the ideXlab platform.
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Disentangling Peronospora on Papaver: Phylogenetics, Taxonomy, Nomenclature and Host Range of Downy Mildew of Opium Poppy (Papaver somniferum) and Related Species
PloS one, 2014Co-Authors: Hermann Voglmayr, Miguel Montes-borrego, Blanca B. LandaAbstract:Based on sequence data from ITS rDNA, cox1 and cox2, six Peronospora species are recognised as phylogenetically distinct on various Papaver species. The host ranges of the four already described species P. arborescens, P. argemones, P. cristata and P. meconopsidis are clarified. Based on sequence data and morphology, two new species, P. apula and P. somniferi, are described from Papaver apulum and P. somniferum, respectively. The second Peronospora species parasitizing Papaver somniferum, that was only recently recorded as Peronospora cristata from Tasmania, is shown to represent a distinct taxon, P. meconopsidis, originally described from Meconopsis cambrica. It is shown that P. meconopsidis on Papaver somniferum is also present and widespread in Europe and Asia, but has been overlooked due to confusion with P. somniferi and due to less prominent, localized disease symptoms. Oospores are reported for the first time for P. meconopsidis from Asian collections on Papaver somniferum. Morphological descriptions, illustrations and a key are provided for all described Peronospora species on Papaver. cox1 and cox2 sequence data are confirmed as equally good barcoding loci for reliable Peronospora species identification, whereas ITS rDNA does sometimes not resolve species boundaries. Molecular phylogenetic data reveal high host specificity of Peronospora on Papaver, which has the important phytopathological implication that wild Papaver spp. cannot play any role as primary inoculum source for downy mildew epidemics in cultivated opium poppy crops.
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A Nested-Polymerase Chain Reaction Protocol for Detection and Population Biology Studies of Peronospora arborescens, the Downy Mildew Pathogen of Opium Poppy, Using Herbarium Specimens and Asymptomatic, Fresh Plant Tissues
Phytopathology, 2009Co-Authors: Miguel Montes-borrego, Francisco Javier Muñoz Ledesma, Rafael M. Jiménez-díaz, Blanca B. LandaAbstract:Montes-Borrego, M., Munoz Ledesma, F. J., Jimenez-Diaz, R. M., and Landa, B. B. 2009. A nested-polymerase chain reaction protocol for detection and population biology studies of Peronospora arborescens, the downy mildew pathogen of opium poppy, using herbarium specimens and asymptomatic, fresh plant tissues. Phytopathology 99:73-81. A sensitive nested-polymerase chain reaction (PCR) protocol was developed using either of two primer pairs that improves the in planta detection of Peronospora arborescens DNA. The new protocol represented an increase in sensitivity of 100- to 1,000-fold of detection of the oomycete in opium poppy tissue compared with the detection limit of single PCR using the same primer pairs. The new protocol allowed amplification of 5 to 0.5 fg of Peronospora arborescens DNA mixed with Papaver somniferum DNA. The protocol proved useful for amplifying Peronospora arborescens DNA from 96-year-old herbarium specimens of Papaver spp. and to demonstrate that asymptomatic, systemic infections by Peronospora arborescens can occur in wild Papaver spp. as well as in cultivated opium poppy. Also, the increase in sensitivity of the protocol made possible the detection of seedborne Peronospora arborescens in commercial opium poppy seed stocks in Spain with a high frequency, which poses a threat for pathogen spread. Direct sequencing of purified amplicons allowed alignment of a Peronospora arborescens internal transcribed spacer (ITS) ribosomal DNA (rDNA) sequence up to 730-bp long when combining the sequences obtained with the two primer sets. Maximum parsimony analysis of amplified Peronospora arborescens ITS rDNA sequences from specimens of Papaver dubium, P. hybridum, P. rhoeas, and P. somniferum from different countries indicated for the first time that a degree of host specificity may exist within populations of Peronospora arborescens. The reported protocol will be useful for epidemiological and biogeographical studies of downy mildew diseases as well as to unravel misclassification of Peronospora arborescens and Peronospora cristata, the reported causal agents of the opium poppy downy mildew disease.
Veniero Gambaro - One of the best experts on this subject based on the ideXlab platform.
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Analysis of fluid extracts obtained from Papaver rhoeas petals contaminated with Papaver bracteatum petals.
Planta medica, 2012Co-Authors: Veniero Gambaro, Paola Minghetti, Sebastiano Arnoldi, Maria Laura Colombo, Lucia Dellʼacqua, Antonella Casiraghi, Katia Guerrini, Fiorenza Farè, Gabriella RodaAbstract:In this paper, we report a case of misidentification of medicinal plants involving dried petals of Papaver rhoeas (red poppy) contaminated with Papaver bracteatum (scarlet poppy) petals. Preliminary TLC analysis indicated the presence of thebaine either in the fluid extracts or in the petals. It was therefore necessary to carry out an accurate botanic examination of the plant material, which revealed contamination of the red poppy petals with scarlet poppy petals. Moreover, to confirm the adulteration, we developed and validated an efficient, reversed-phase ion pair HPLC method for determination of the alkaloids specific for the Papaver species. Six petal batches and five commercial fluid extracts were analyzed. Only one petal batch from Iran contained thebaine and its analogue oripavine while the alkaloids typical for the Papaver bracteatum species were identified in all fluid extracts, meaning that they were all prepared with contaminated petals.
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Analysis of fluid extracts obtained with Papaver rhoeas petals contaminated with Papaver bracteatum petals
'Georg Thieme Verlag KG', 2012Co-Authors: Veniero Gambaro, Paola Minghetti, Sebastiano Arnoldi, Maria Laura Colombo, Antonella Casiraghi, Katia Guerrini, L. Dell’, F. Farè, Gabriella RodaAbstract:In this paper we refer a case of misidentification of medicinal plants involving dried petals of Papaver rhoeas contaminated with Papaver bracteatum petals. Preliminarily, TLC analysis evidenced the presence of thebaine either in the fluid extracts or in the petals. In this frame it was necessary to carry out an accurate botanic examination of the vegetable material which revealed the contamination of the red poppy petals with scarlet poppy petals. Moreover to confirm the adulteration, we developed and validated an efficient reverse phase ion pair HPLC method for the determination of the alkaloids contained in the Papaver species. Six petal batches and five commercial fluid extracts were analysed. Only one petal batch coming from Iran resulted to contain thebaine and its analogue oripavine, while all the fluid extracts contained the alkaloids typical of the Papaver bracteatum species, meaning that they were all prepared with contaminated petals
