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Littérature scientifique sur le sujet « Pyrrolizidine alkaloid »

Auteur : Grafiati
Publié le 4 juin 2021
Mis à jour le 1 février 2022

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Articles de revues sur le sujet "Pyrrolizidine alkaloid"

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Nickisch-Rosenegk, Eva von, Dietrich Schneider et Michael Wink. « Time-Course of Pyrrolizidine Alkaloid Processing in the Alkaloid Exploiting Arctiid Moth, Creatonotos transiens ». Zeitschrift für Naturforschung C 45, no 7-8 (1 août 1990) : 881–94. http://dx.doi.org/10.1515/znc-1990-7-822.

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Abstract The processing of dietary pyrrolizidine alkaloids by larvae and adults of the arctiid moth Creatonotos transiens was studied in time-course experiments: In larvae, pyrrolizidine alkaloid uptake is quickly followed by the transformation of the alkaloids into their N-oxides. Further- more, if 7 S-heliotrine is applied, a stereochemical inversion of the hydroxyl group at C 7 to 7 R-heliotrine can be observed within 48 h of feeding. The rate of this biotransformation is substantially higher in males which use the 7 R-form later as a precursor for the biosynthesis of 7 R-hydroxydanaidal, a pheromone. The resorbed pyrrolizidine alkaloids are deposited in the integument within 48 h, where they remain stored during the larval, pupal and partly also the imaginal stages. Virtually no alkaloids are lost during ecdysis. Some pyrrolizidine alkaloids can be recovered from the meconium which is released at eclosion by the imagines especially when disturbed. In the adults pyrrolizidine alkaloids are processed in different ways by the two sexes: In females, about 50-80% of total alkaloids are transferred from the integument to the ovaries and the eggs within 2 - 3 days after eclosion. If females mate with alkaloid-rich males they additionally receive with the spermatophore up to 290 jig pyrrolizidine alkaloid, which are further translocated to the eggs. A biparental endowment of eggs with acquired defence alkaloids is thus achieved. In males, 30-50% of pyrrolizidine alkaloids remain in the integu- ment; about 10 - 30% are transferred to the scent organ, the corema, where they are converted into 7 R-hydroxydanaidal. Another part (about 40%) is passed to the spermatophore. In the laboratory experiments, the sizes of the coremata and their respective 7 R-hydroxydanaidal contents are strongly dependent on the availability of dietary pyrrolizidine alkaloids during L6 and especially L7 stages. In the L7 stage even short-term feeding (4-6 h) on Senecio jaco- haea is sufficient to induce large coremata.
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Kopp, Thomas, Mona Abdel-Tawab et Boris Mizaikoff. « Core Imprinting : An Alternative and Economic Approach for Depleting Pyrrolizidine Alkaloids in Herbal Extracts ». Planta Medica International Open 7, no 01 (18 mars 2020) : e26-e33. http://dx.doi.org/10.1055/a-1121-4868.

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AbstractDue to the high toxicity of pyrrolizidine alkaloids, in 2011, the German Federal Institute of Risk Assessment recommended that their daily intake limit should be no more than 0.007 µg/kg body weight. The risk of ingesting these substances in herbal preparations, either from their inherent presence in plants or through contamination with pyrrolizidine alkaloid-containing weeds, should not be underestimated. A promising molecular imprinted polymer was developed previously to minimise exposure to these compounds. Due to the high costs of the template and the risk of template bleeding, an alternative and more economic pyrrolizidine alkaloid depleting strategy is still required. Core imprinting, which focuses on the most important structural element in the target molecule, was investigated using triethylamine and tetraethylammonium as easily available and cheap alternative templates. The suitability of core imprinting was demonstrated using a pyrrolizidine alkaloid standard solution if an excess of an alternative template compared to monocrotaline was used for imprinting. Matrix trials in pyrrolizidine alkaloid-spiked Mentha piperita, Chelidonium majus, Glycyrrhiza glabra, and Matricaria chamomilla extracts containing Echium vulgare revealed better pyrrolizidine alkaloid binding than demonstrated for the original molecular imprinted polymer. Echimidine and echimidine-N-oxide were depleted in the range of 31.8–70.0 and 26.1–45.1%, respectively. However, solvent-dependent differences in pyrrolizidine alkaloid binding and inherent plant analytical marker compounds were observed. Hence, binding of analytical marker compounds was better minimised in methanolic than in ethanolic extracts. The present study reveals core imprinting to be an economic alternative approach for depleting pyrrolizidine alkaloids in plant extracts.
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Kopp, Thomas, Mona Abdel-Tawab, Martin Khoeiklang et Boris Mizaikoff. « Development of a Selective Adsorbing Material for Binding of Pyrrolizidine Alkaloids in Herbal Extracts, Based on Molecular Group Imprinting ». Planta Medica 85, no 13 (5 août 2019) : 1107–13. http://dx.doi.org/10.1055/a-0961-2658.

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AbstractPyrrolizidine alkaloids are secondary plant constituents that became a subject of public concern because of their hepatotoxic, pneumotoxic, genotoxic, and cytotoxic effects. Due to disregardful harvesting and/or contamination with pyrrolizidine alkaloid-containing plants, there is a high risk of ingesting these substances with plant extracts or natural products. The limit for the daily intake was set to 0.007 µg/kg body weight. If contained in an extract, cleanup methods may help to minimize the pyrrolizidine alkaloid concentration. For this purpose, a material for depleting pyrrolizidine alkaloids in herbal preparations was developed based on the approach of molecular imprinting using monocrotaline. Molecular imprinted polymers are substances with specific binding characteristics, depending on the template used for imprinting. By means of group imprinting, only one molecule is used for creating selective cavities for many molecular pyrrolizidine alkaloid variations. Design of Experiment was used for the development using a 25 screening plan resulting in 64 polymers (32 MIPs/32 NIPs). Rebinding trials revealed that the developed material can compete with common cation exchangers and is more suitable for depleting pyrrolizidine alkaloids than C18- material. Matrix trials using an extract from Chelidonium majus show that there is sufficient binding capacity for pyrrolizidine alkaloids (80%), but the material is lacking in selectivity towards pyrrolizidine alkaloids in the presence of other alkaloids with similar functional groups such as berberine, chelidonine, and coptisine. Beyond this interaction, the selectivity could be proven for other structurally different compounds on the example of chelidonic acid.
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Kopp, Thomas, Liesa Salzer, Mona Abdel-Tawab et Boris Mizaikoff. « Efficient Extraction of Pyrrolizidine Alkaloids from Plants by Pressurised Liquid Extraction – A Preliminary Study ». Planta Medica 86, no 01 (21 octobre 2019) : 85–90. http://dx.doi.org/10.1055/a-1023-7419.

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AbstractPyrrolizidine alkaloids and their corresponding pyrrolizidine alkaloid-N-oxides are secondary plant constituents that became the subject of public concern due to their hepatotoxic, pneumotoxic, genotoxic, and cytotoxic effects. In contrast to the well-established analytical separation and detection methods, only a few studies have investigated the extraction of pyrrolizidine alkaloids/pyrrolizidine alkaloid-N-oxides from plant material. In this study, we have applied pressurized liquid extraction with the aim of evaluating the effect of various parameters on the recovery of pyrrolizidine alkaloids. The nature of the modifier (various acids, NH3) added to the aqueous extraction solvent, its concentration (1 or 5%), and the temperature (50 – 125 °C) were systematically varied. To analyse a wide range of structurally different pyrrolizidine alkaloids, Jacobaea vulgaris (syn. Senecio jacobaea), Tussilago farfara, and Symphytum officinale were included. Pyrrolizidine alkaloids were quantified by HPLC-MS/MS and the results obtained by pressurised liquid extraction were compared with the amount of pyrrolizidine alkaloids determined by an official reference method. Using this approach, increased rates of recovery were obtained for J. vulgaris (up to 174.4%), T. farfara (up to 156.5%), and S. officinale (up to 288.7%). Hence, pressurised liquid extraction was found to be a promising strategy for the complete and automated extraction of pyrrolizidine alkaloids, which could advantageously replace other time- and solvent-consuming extraction methods.
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El-Shazly, Assem. « Pyrrolizidine Alkaloid Profiles of Some Senecio Species from Egypt ». Zeitschrift für Naturforschung C 57, no 5-6 (1 juin 2002) : 429–33. http://dx.doi.org/10.1515/znc-2002-5-604.

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Alkaloid profiles of two Egyptian Senecio species (Senecio aegyptius var. discoideus and S. desfontainei) in addition to a cultivated species (S. cineraria) were studied using capillary GLC and GLC-mass spectrometry with respect to pyrrolizidine alkaloids (PAs). Four alkaloids were identified in S. aegyptius var. discoideus, 8 in S. desfontainei and 13 in S. cineraria. Some of these alkaloids have not been reported from these plants. The alkaloidal pattern of different plant organs (flowers, leaves, stem, root) were also investigated. Senecionine has been found to be a one of the major alkaloid in all studied species, it was isolated and its structure was elucidated by 1H- and 13C-NMR.
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Edgar, J. A., H. J. Lin, C. R. Kumana et M. M. T. Ng. « Pyrrolizidine Alkaloid Composition of Three Chinese Medicinal Herbs, Eupatorium cannabinum, E. japonicum and Crotalaria assamica ». American Journal of Chinese Medicine 20, no 03n04 (janvier 1992) : 281–88. http://dx.doi.org/10.1142/s0192415x92000291.

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The pyrrolizidine alkaloid composition of three Chinese herbs, "pei lan", "cheng gan cao" and "zi xiao rong" identified respectively as Eupatorium cannabinum, Eupatorium japonicum (Compositae) and Crotalaria assamica (Leguminosae), were studied by fast atom bombardment mass spectrometry and gas chromatography-electron impact mass spectrometry. Viridiflorine, cynaustraline, amabiline, supinine, echinatine, rinderine and isomers of these alkaloids were found in the Eupatorium species. Monocrotaline was the only pyrrolizidine alkaloid detected in the Crotalaria species.
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Lin, Ge, et Mengbi Yang. « Biotransformation of Pyrrolizidine alkaloid N-Oxide to hepatotoxic Pyrrolizidine alkaloid ». Drug Metabolism and Pharmacokinetics 34, no 1 (janvier 2019) : S58—S59. http://dx.doi.org/10.1016/j.dmpk.2018.09.205.

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Hungerford, Natasha L., Steve J. Carter, Shalona R. Anuj, Benjamin L. L. Tan, Darina Hnatko, Christopher L. Martin, Elipsha Sharma et al. « Analysis of Pyrrolizidine Alkaloids in Queensland Honey : Using Low Temperature Chromatography to Resolve Stereoisomers and Identify Botanical Sources by UHPLC-MS/MS ». Toxins 11, no 12 (11 décembre 2019) : 726. http://dx.doi.org/10.3390/toxins11120726.

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Pyrrolizidine alkaloids (PAs) are a diverse group of plant secondary metabolites with known varied toxicity. Consumption of 1,2-unsaturated PAs has been linked to acute and chronic liver damage, carcinogenicity and death, in livestock and humans, making their presence in food of concern to food regulators in Australia and internationally. In this survey, honey samples sourced from markets and shops in Queensland (Australia), were analysed by high-resolution Orbitrap UHPLC-MS/MS for 30 common PAs. Relationships between the occurrence of pyrrolizidine alkaloids and the botanical origin of the honey are essential as pyrrolizidine alkaloid contamination at up to 3300 ng/g were detected. In this study, the predominant alkaloids detected were isomeric PAs, lycopsamine, indicine and intermedine, exhibiting identical MS/MS spectra, along with lesser amounts of each of their N-oxides. Crucially, chromatographic UHPLC conditions were optimised by operation at low temperature (5 °C) to resolve these key isomeric PAs. Such separation of these isomers by UHPLC, enabled the relative proportions of these PAs present in honey to be compared to alkaloid levels in suspect source plants. Overall plant pyrrolizidine alkaloid profiles were compared to those found in honey samples to help identify the most important plants responsible for honey contamination. The native Australian vines of Parsonsia spp. are proposed as a likely contributor to high levels of lycopsamine in many of the honeys surveyed. Botanical origin information such as this, gained via low temperature chromatographic resolution of isomeric PAs, will be very valuable in identifying region of origin for honey samples.
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Chen, Xue-Peng, Lie-Feng Ma et Zha-Jun Zhan. « A New Pyrrolizidine Alkaloid from Penicillium Expansum ». Journal of Chemical Research 41, no 2 (février 2017) : 93–94. http://dx.doi.org/10.3184/174751917x14858862342142.

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A new pyrrolizidine alkaloid with an unusual O-bridge, named penexpandine, was isolated from the cultures of Penicillium expansum ACCC 30904, together with two known alkaloids, communesins A and B. The structure of the new compound was established by detailed analyses of the spectroscopic data, especially 1D- and 2D-NMR and HR-ESI-MS
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Chizzola, Remigius. « Pyrrolizidine Alkaloids in Adenostyles alliariae and A. glabra from the Austrian Alps ». Natural Product Communications 10, no 7 (juillet 2015) : 1934578X1501000. http://dx.doi.org/10.1177/1934578x1501000710.

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The alkaloid content of Adenostyles alliariae and A. glabra (Asteraceae) has been evaluated. Both species contain toxic macrocyclic unsaturated pyrrolizidine alkaloids with seneciphylline as the main compound accounting for more than 90% of the alkaloid fraction in all above ground plant parts. Further alkaloids were spartioidine, acetyl-senciphylline and senecionine. Inflorescences showed the highest alkaloid contents with 21.1 and 13.4 mg/g in A. alliariae and A. glabra, respectively. Stems and leaves had 2–3 times lower contents. Therefore, these Adenostyles species must be considered as highly toxic plants.
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Thèses sur le sujet "Pyrrolizidine alkaloid"

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Fortune, Grady Thomas Jr. « Structure-activity relationships in semisynthetic pyrrolizidine alkaloid antitumor agents ». Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/27371.

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Faulkner, Jerome Ralph. « INTERMEDIATE STEPS OF LOLINE ALKALOID BIOSYNTHESIS ». UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/209.

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Epichloë species and their anamorphs, Neotyphodium species, are fungal endophytes that inhabit cool-season grasses and often produce bioprotective alkaloids. These alkaloids include lolines, which are insecticidal and insect feeding deterrents. Lolines are exo-1-aminopyrrolizidines with an oxygen bridge between carbons 2 and 7, and are usually methylated and formylated or acetylated on the 1-amine. In previously published studies lolines were shown to be derived from the amino acids L-proline and L-homoserine. In addition the gene cluster involved in loline-alkaloid biosynthesis has also been characterized. In this dissertation a survey of plant-endophyte symbioses revealed a phenotype with only N-acetylnorloline. This phenotype provided insights into loline alkaloid production. This dissertation focuses on determining the steps to loline biosynthesis after the amino acid precursors. The study involves feeding isotopically labeled potential precursors to loline-alkaloid-producing cultures of Neotyphodium uncinatum, as well as RNA interference (RNAi) of N. uncinatum genes for steps in the pathway. Synthesized deuterated compounds were fed to loline-alkaloid-producing cultures of N. uncinatum to test their possible roles as precursors or intermediates in the loline-alkaloid pathway. N-Formylloline was extracted from the cultures and assayed by GCMS for incorporation of the deuterium label. The results indicated that N-(3-amino, 3-carboxy)propylproline and exo-1-aminopyrrolizidine are intermediates in the loline-alkaloid biosynthetic pathway. Plasmids were also designed for expression of double-stranded RNA homologous to loline-alkaloid biosynthesis genes, and introduced by transformation into N. uncinatum. This RNAi strategy resulted in fungal transformants altered in loline-alkaloid profiles. The RNAi results indicated that N-acetyl-1-aminopyrrolizidine is the intermediate before oxygen bridge formation. Based on the results of this study and the likely roles of the loline-alkaloid biosynthesis genes inferred from signature sequences of their predicted protein products, I propose a pathway of bond formation steps in loline-alkaloid biosynthesis.
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Fleischmann, Thomas John. « Semisynthetic pyrrolizidine alkaloid antitumor agents and the toxic component of eupatorium rugosum ». Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/30343.

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Bhardwaj, Minakshi. « FORMATION OF THE ETHER BRIDGE IN THE LOLINE ALKALOID BIOSYNTHETIC PATHWAY ». UKnowledge, 2017. http://uknowledge.uky.edu/chemistry_etds/75.

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Lolines are specialized metabolites produced by endophytic fungi, such as Neotyphodium and Epichloë species, that are in symbiotic relationships with cool-season grasses. Lolines are vital for the survival of the grasses because their insecticidal and antifeedant properties protect the plant from insect herbivory. Although lolines have various bioactivities, they do not have any concomitant antimammalian activities. Lolines have complex structures that are unique among naturally occurring pyrrolizidine alkaloids. Lolines have four contiguous stereocenters, and they contain an ether bridge connecting C(2) and C(7) of the pyrrolizidine ring. An ether bridge connecting bridgehead C atoms is unusual in natural products and leads to interesting questions about the biosynthesis of lolines in fungal endophytes. Dr. Pan, who was a graduate student in Dr. Schardl Lab at University of Kentucky, isolated a novel metabolite, 1-exo-acetamidopyrrolizidine (AcAP). She observed that AcAP was accumulating in naturally occurring and artificial lolO mutants. I synthesized an authentic sample of (±)-AcAP and compared it spectroscopically with AcAP isolated from a lolO mutant to determine the structure and stereochemistry of the natural product. I was also able to grow crystals of synthetic (±)-AcAP, X-ray analysis of which further supported our structure assignment. There were two possible explanations for the fact that a missing or nonfunctional LolO led to the accumulation of AcAP: that AcAP was the actual substrate of LolO, or that it was a shunt product derived from the real substrate of LolO, 1-exo-aminopyrrolizidine (AP), and that was produced only when LolO was not available to oxidize AP. To distinguish between the two hypotheses, I synthesized 2´,2´,2´,3-[2H4]-AcAP. Dr. Pan used this material to confirm that AcAP was an intermediate in loline alkaloid biosynthesis, not a shunt product. To determine the product of LolO acting on AcAP, Dr. Pan expressed LolO in yeast (Saccharomyces cerevisiae). When Dr. Pan fed AcAP (synthesized by me) to the modified organism, it produced NANL, suggesting that LolO catalyzed two C–H activations of AcAP and the formation of both C–O bonds of the ether bridge in NANL, a highly unusual transformation. Dr. Chang then cloned, expressed, and purified LolO and incubated it with (±)-AcAP, 2-oxoglutarate, and O2. He observed the production of NANL, further confirming the function of LolO. Dr. Chang also observed an intermediate, which we tentatively identified as 2-hydroxy-AcAP. In order to determine whether the initial hydroxylation of AcAP catalyzed by LolO occurred at C(2) or C(7), I prepared (±)-7,7-[2H2]- and (±)-2,2,8-[2H3]-AcAP. When Dr. Pan measured the rate of LolO-catalyzed hydroxylation of these substrates under conditions under which only one C–H activation would occur, she observed a very large kinetic isotope effect when C(2) was deuterated, but not when C(7) was deuterated, establishing that the initial hydroxylation of AcAP occurred at the C(2) position. In order to determine the stereochemical course of C–H bond oxidation by LolO at C(2) and C(7) of AcAP, I synthesized trans- and cis-3-[2H]-Pro and (2S,3R)-3-[2H]- and (2S,3S)-2,3-[2H2]-Asp. Feeding experiments with these substrates carried out by both Dr. Pan (Pro) and me (Asp) showed that at both the C(2) and C(7) positions of AcAP, LolO abstracted the endo H atoms during ether bridge formation. In summary, feeding experiments with deuterated (±)-AcAP derivatives and its amino acid precursors have shown that AcAP is an intermediate in loline biosynthesis. We have shown that LolO catalyzes the four-electron oxidation of AcAP at the endo C(2) position first and then the endo C(7) position to give NANL.
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Davis, Jonathan C. « Section one : photochemical methodologies towards the pyrrolizidine and indolizidine alkaloid skeleta ; section two ; synthesis of novel leukotriene photoaffinity labels ». Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360717.

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Kruse, Lars Hendrik [Verfasser], Dietrich [Akademischer Betreuer] Ober et Axel [Gutachter] Scheidig. « A multifaceted approach to identify unknown enzymes of pyrrolizidine alkaloid biosynthesis / Lars Hendrik Kruse ; Gutachter : Axel Scheidig ; Betreuer : Dietrich Ober ». Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1210925060/34.

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Kruse, Lars Hendrik Verfasser], Dietrich [Akademischer Betreuer] [Ober et Axel [Gutachter] Scheidig. « A multifaceted approach to identify unknown enzymes of pyrrolizidine alkaloid biosynthesis / Lars Hendrik Kruse ; Gutachter : Axel Scheidig ; Betreuer : Dietrich Ober ». Kiel : Universitätsbibliothek Kiel, 2017. http://nbn-resolving.de/urn:nbn:de:gbv:8-diss-211136.

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Dener, Jeffrey Mark. « Part I, the enantioselective synthesis of pyrrolizidine alkaloids using alpha-acylamino radical cyclizations ; Part II, the enantioselective synthesis of the indolizidine alkaloid (-)-swainsonine using an alpha-acylamino radical cyclization / ». The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487591658176567.

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Vevers, William F. « Deoxynivalenol : toxicological profile and potential for reducing cereal grain contamination using bacterial additives in fermented animal feed ». Thesis, University of Plymouth, 2015. http://hdl.handle.net/10026.1/4305.

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Deoxynivalenol (DON) contamination of grain destined for animal feeds is a major toxicological risk to monogastrics and is suspected of restricting productivity in ruminants. Whereas bacterial additives have been developed that can detoxify DON in the rumen and lower intestine, there are currently no commercial inoculants able to perform this task in crimped grain (CG) silage, a regionally important method of moist grain preservation based on homo- and heterofermentative lactic acid bacteria or chemical additives. Determining whether this ensiling process alongside the action of detoxifying bacteria has the potential to remove DON in CG prior to ingestion, was explored in mini-silo ensiling experiments. CG was heat treated (100 °C, 60 min) or ensiled fresh in triplicate 50 g silos, spiked with 5 mg/kg DON and inoculated with lactic acid bacteria derived from wild birds, natural epiphytic inoculants and commercially sourced silage additives (21 d). DON recovery was only significantly reduced (31.2 ± 14.4% recovery, p < 0.001, n= 30) by heat treatment, as determined by IAC-RP-HPLC-UV. Bacterial assemblage analysis by 16S rRNA PCR-DGGE-SEQ identified Weissella cibaria, Pantoea agglomerans, Bacillus subtilis, B. licheniformis and Hafnia alvei as candidate detoxification agents, of which W. cibaria and H. alvei decreased DON recovery in vitro (11.3 and 6.2% recovery respectively, p < 0.05, n = 18), which translated to inoculated W. cibaria yielding a decrease in DON recovery (67.2± 14.4%, 28 d) in naturally contaminated crimped wheat (13.5 ± 1.0 mg/kg, 35-40% moisture, p < 0.05, n =15). As W. cibaria is a lactic acid bacteria already associated with fermented CG by default it has promise as a novel DON detoxification agent in CG silage. DON is however just one of many hepatotoxic co-contaminants. Retrorsine, a DNA-crosslinking pyrrolizidine alkaloid derived from Ragwort (Senecio sp.) was investigated for interactive toxicity with DON in an in vitro co-exposure experiment. HepG2 cells were exposed to Log10 multifactorial binary exposures for 48 h followed by a suite of assays to elucidate mechanisms of interactive cytotoxicity, genotoxicity and modulation of the proteome. Retrorsine was tentatively confirmed to form DNA/protein crosslinks in the comet, micronucleus and crosslinking assays, whilst DON was found to potently induce cytotoxicity and apoptosis. Co-exposure yielded a complex toxicity response, with low doses yielding antagonistic effects and high doses trending towards additive effects, although DON dose was generally the principle component. The difficulties associated with undertaking an interactive toxicity study where both toxins have multiple metabolic and cellular targets are highlighted.
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Choi, Joong-Kwon. « Synthesis of pyrrolizidine alkaloids / ». The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487259125219504.

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Livres sur le sujet "Pyrrolizidine alkaloid"

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Chemistry and toxicology of pyrrolizidine alkaloids. London : Academic Press, 1986.

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Hol, Wilhelmina Hermina Geertruida. The role of pyrrolizidine alkaloids from Senecio jacobaea in the defence against fungi. [Leiden : Universiteit Leiden, 2003.

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3

Máčel, Mirka. On the evolution of the diversity of pyrrolizidine alkaloids : The role of insects as selective forces. [Leiden : Universiteit Leiden, 2003.

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Deyo, James A. Immunotoxicity of the pyrrolizidine alkaloid monocrotaline in C57B1/6 mice. 1991.

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Chung, Woon-Gye. Comparative metabolism of the pyrrolizidine alkaloid senecionine in rat and guinea pig. 1993.

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Gray, Diane R. Bacterial 16S ribosomal DNA analysis of pyrrolizidine alkaloid detoxifying enrichments from the ovine rumen. 1998.

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World Health Organization (WHO). Pyrrolizidine Alkaloids. World Health Organization, 1988.

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Pyrrolizidine alkaloids. Geneva : World Health Organization, 1988.

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M, Rizk A., dir. Naturally occurring pyrrolizidine alkaloids. Boca Raton, Fla : CRC Press, 1991.

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Pyrrolizidine Alkaloids Health and Safety Guide. World Health Organization, 1989.

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Chapitres de livres sur le sujet "Pyrrolizidine alkaloid"

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Neuman, Manuela G. « Pyrrolizidine Alkaloid-Induced Toxicity to the Liver ». Dans Natural Products, 1383–95. Berlin, Heidelberg : Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-22144-6_92.

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Buhler, Donald R., Cristobal L. Miranda, Bogdan Kedzierski et Ralph L. Reed. « Mechanisms for Pyrrolizidine Alkaloid Activation and Detoxification ». Dans Advances in Experimental Medicine and Biology, 597–603. Boston, MA : Springer New York, 1991. http://dx.doi.org/10.1007/978-1-4684-5877-0_75.

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Bober, Mary A., Mark J. Kurth, Larry A. Milco, David M. Roseman, R. Bryan Miller et Henry J. Segal. « A Pyrrolizidine Alkaloid Enzyme-Linked Immunosorbent Assay Detection Strategy ». Dans ACS Symposium Series, 176–83. Washington, DC : American Chemical Society, 1990. http://dx.doi.org/10.1021/bk-1990-0451.ch016.

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Ralphs, M. H., et D. N. Ueckert. « Other Toxic Pyrrolizidine Alkaloid-Containing Plants : Importance, Distribution, and Control ». Dans Noxious Range Weeds, 429–37. New York : CRC Press, 2021. http://dx.doi.org/10.1201/9780429046483-43.

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Huxtable, R. J., R. Bowers, A. R. Mattocks et M. Michnicka. « Sulfur Conjugates as Putative Pneumotoxic Metabolites of the Pyrrolizidine Alkaloid, Monocrotaline ». Dans Advances in Experimental Medicine and Biology, 605–12. Boston, MA : Springer New York, 1991. http://dx.doi.org/10.1007/978-1-4684-5877-0_76.

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Yan, Chong Chao, et Ryan J. Huxtable. « Effect of Taurine on Toxicity of the Pyrrolizidine Alkaloid Monocrotaline in Rats ». Dans Advances in Experimental Medicine and Biology, 315–25. Boston, MA : Springer US, 1996. http://dx.doi.org/10.1007/978-1-4899-0182-8_33.

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de Boer, Nico J. « Pyrrolizidine alkaloid distribution in Senecio jacobaea rosettes minimises losses to generalist feeding ». Dans Proceedings of the 10th International Symposium on Insect-Plant Relationships, 169–73. Dordrecht : Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-1890-5_21.

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Hasal, Steve J., Yun Sun, Chong Chao Yan, Klaus Brendel et Ryan J. Huxtable. « Effects of Taurine in Precision-Cut Liver Slices Exposed to the Pyrrolizidine Alkaloid, Retrorsine ». Dans Advances in Experimental Medicine and Biology, 79–83. Boston, MA : Springer US, 1998. http://dx.doi.org/10.1007/978-1-4899-0117-0_10.

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Sun, Y., S. J. Hasal, C. C. Yan, K. Brendel et R. J. Huxtable. « Pyrrolizidine Alkaloid-Induced Depletion of Taurine from Rat Liver In Vivo and In Vitro ». Dans Advances in Experimental Medicine and Biology, 71–77. Boston, MA : Springer US, 1998. http://dx.doi.org/10.1007/978-1-4899-0117-0_9.

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Liu, Dongyou. « Pyrrolizidine Alkaloids ». Dans Handbook of Foodborne Diseases, 1109–14. Boca Raton : Taylor & Francis, [2019] | Series : Food microbiology series | “A CRC title, part of the Taylor & Francis imprint, a member of the Taylor & Francis Group, the academic division of T&F Informa plc.” : CRC Press, 2018. http://dx.doi.org/10.1201/b22030-104.

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Actes de conférences sur le sujet "Pyrrolizidine alkaloid"

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Schrenk, D. « Provisional relative potency factors for pyrrolizidine alkaloids – scientifically justified ? » Dans Phytotherapiekongress 2019. Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-1697263.

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Ober, Dietrich. « Repeated evolution of insect adaptations to toxic pyrrolizidine alkaloids of plants ». Dans 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.94260.

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Rutz, L., L. Gao et D. Schrenk. « Structure-dependent cytotoxicity of different pyrrolizidine alkaloids in primary rat hepatocytes ». Dans Phytotherapiekongress 2019. Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-1697293.

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Hadi, NSA, EE Bankoglu, O. Kelber, H. Sievers et H. Stopper. « Studies on mechanism of genotoxicity of selected pyrrolizidine alkaloids in HepG2 cells in vitro ». Dans Jubiläumskongress Phytotherapie 2021 Leib und Magen – Arzneipflanzen in der Gastroenterologie 50 Jahre Gesellschaft für Phytotherapie. Georg Thieme Verlag KG, 2021. http://dx.doi.org/10.1055/s-0041-1731499.

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Haas, M., K. Wirachowski, JH Küpper, D. Schrenk et J. Fahrer. « Structure-dependent genotoxicity and cytotoxicity of eleven pyrrolizidine alkaloids in CYP3A4-proficient human liver cells ». Dans Jubiläumskongress Phytotherapie 2021 Leib und Magen – Arzneipflanzen in der Gastroenterologie 50 Jahre Gesellschaft für Phytotherapie. Georg Thieme Verlag KG, 2021. http://dx.doi.org/10.1055/s-0041-1731472.

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Schenk, A., B. Siewert, S. Toff et J. Drewe. « Determination of 34 pyrrolizidine alkaloids (PA) as contaminants in various plant extracts using UHPLC-ToF-HRMS ». Dans GA 2017 – Book of Abstracts. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1608497.

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Forsch, K., B. Siewert, L. Disch, M. Unger et J. Drewe. « In vitro screening of acute hepatic cytotoxicity of pyrrolizidine alkaloids in human and rodent hepatic cell lines ». Dans GA 2017 – Book of Abstracts. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1608451.

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Rapports d'organisations sur le sujet "Pyrrolizidine alkaloid"

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Pereboom, D. P. K. H., M. de Nijs, J. G. J. Mol et P. P. J. Mulder. Research study for pyrrolizidine alkaloids in alfalfa and herbal tea : EURLPT-MP02 (2019). Wageningen : Wageningen Food Safety Research, 2021. http://dx.doi.org/10.18174/545714.

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