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Daniel G Panaccione - One of the best experts on this subject based on the ideXlab platform.
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diversification of Ergot Alkaloids and heritable fungal symbionts in morning glories
bioRxiv, 2021Co-Authors: Wesley T Beaulieu, Daniel G Panaccione, Keith Clay, Q N Quach, R E Miller, K L SmootAbstract:Heritable microorganisms play critical roles in life cycles of many macro-organisms but their prevalence and functional roles are unknown for most plants. Bioactive Ergot Alkaloids produced by heritable Periglandula fungi occur in some morning glories (Convolvulaceae), similar to Ergot Alkaloids in grasses infected with related fungi. Ergot Alkaloids have been of longstanding interest given their toxic effects, psychoactive properties, and medical applications. Here we show that Ergot Alkaloids are concentrated in four morning glory clades exhibiting differences in alkaloid profiles and are more prevalent in species with larger seeds than those with smaller seeds. Further, we found a phylogenetically-independent, positive correlation between seed mass and alkaloid concentrations in symbiotic species. Our findings suggest that heritable symbiosis has diversified among particular clades by vertical transmission through seeds combined with host speciation, and that Ergot Alkaloids are particularly beneficial to species with larger seeds. Our results are consistent with the defensive symbiosis hypothesis where bioactive Ergot Alkaloids from Periglandula symbionts protect seeds and seedlings from natural enemies, and provide a framework for exploring microbial chemistry in other plant-microbe interactions.
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Several Metarhizium Species Produce Ergot Alkaloids in a Condition-Specific Manner.
Applied and environmental microbiology, 2020Co-Authors: Caroline E. Leadmon, Jessi K. Sampson, Matthew D. Maust, Angie M. Macias, Stephen A. Rehner, Matthew T. Kasson, Daniel G PanaccioneAbstract:Genomic sequence data indicate that certain fungi in the genus Metarhizium have the capacity to produce lysergic acid-derived Ergot Alkaloids, but accumulation of Ergot Alkaloids in these fungi has not been demonstrated previously. We assayed several Metarhizium species grown under different conditions for accumulation of Ergot Alkaloids. Isolates of M. brunneum and M. anisopliae accumulated the lysergic acid amides lysergic acid α-hydroxyethyl amide, ergine, and ergonovine on sucrose-yeast extract agar but not on two other tested media. Isolates of six other Metarhizium species did not accumulate Ergot Alkaloids on sucrose-yeast extract agar. Conidia of M. brunneum lacked detectable Ergot Alkaloids, and mycelia of this fungus secreted over 80% of their Ergot alkaloid yield into the culture medium. Isolates of M. brunneum, M. flavoviride, M. robertsii, M. acridum, and M. anisopliae produced high concentrations of Ergot Alkaloids in infected larvae of the model insect Galleria mellonella, but larvae infected with M. pingshaense, M. album, M. majus, and M. guizhouense lacked detectable Ergot Alkaloids. Alkaloid concentrations were significantly higher when insects were alive (as opposed to killed by freezing or gas) at the time of inoculation with M. brunneum Roots of corn and beans were inoculated with M. brunneum or M. flavoviride and global metabolomic analyses indicated that the inoculated roots were colonized, though no Ergot Alkaloids were detected. The data demonstrate that several Metarhizium species produce Ergot Alkaloids of the lysergic acid amide class and that production of Ergot Alkaloids is tightly regulated and associated with insect colonization.IMPORTANCE Our discovery of Ergot Alkaloids in fungi of the genus Metarhizium has agricultural and pharmaceutical implications. Ergot Alkaloids produced by other fungi in the family Clavicipitaceae accumulate in forage grasses or grain crops; in this context they are considered toxins, though their presence also may deter or kill insect pests. Our data report Ergot Alkaloids in Metarhizium species and indicate a close association of Ergot alkaloid accumulation with insect colonization. The lack of accumulation of Alkaloids in spores of the fungi and in plants colonized by the fungi affirms the safety of using Metarhizium species as biocontrol agents. Ergot Alkaloids produced by other fungi have been exploited to produce powerful pharmaceuticals. The class of Ergot Alkaloids discovered in Metarhizium species (lysergic acid amides) and their secretion into the growth medium make Metarhizium species a potential platform for future studies on Ergot alkaloid synthesis and modification.
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Biodiversity of Convolvulaceous species that contain Ergot Alkaloids, Indole Diterpene Alkaloids, and Swainsonine.
Biochemical systematics and ecology, 2019Co-Authors: Daniel Cook, Daniel G Panaccione, Stephen T. Lee, Caroline E. Leadmon, Keith Clay, Dale R GardnerAbstract:Convolvulaceous species have been reported to contain several bioactive principles thought to be toxic to livestock including the calystegines, swainsonine, Ergot Alkaloids, and indole diterpene Alkaloids. Swainsonine, Ergot Alkaloids, and indole diterpene Alkaloids are produced by seed transmitted fungal symbionts associated with their respective plant host, while the calystegines are produced by the plant. To date, Ipomoea asarifolia and Ipomoea muelleri represent the only Ipomoea species and members of the Convolvulaceae known to contain indole diterpene Alkaloids, however several other Convolvulaceous species are reported to contain Ergot Alkaloids. To further explore the biodiversity of species that may contain indole diterpenes, we analyzed several Convolvulaceous species (n=30) for indole diterpene Alkaloids, representing four genera, Argyreia, Ipomoea, Stictocardia, and Turbina, that had been previously reported to contain Ergot Alkaloids. These species were also verified to contain Ergot Alkaloids and subsequently analyzed for swainsonine. Ergot Alkaloids were detected in 18 species representing all four genera screened, indole diterpenes were detected in two Argyreia species and eight Ipomoea species of the 18 that contained Ergot Alkaloids, and swainsonine was detected in two Ipomoea species. The data suggest a strong association exists between the relationship of the Periglandula species associated with each host and the occurrence of the Ergot Alkaloids and/or the indole diterpenes reported here. Likewise there appears to be an association between the occurrence of the respective bioactive principle and the genetic relatedness of the respective host plant species.
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Ergot Alkaloids contribute to virulence in an insect model of invasive aspergillosis
Scientific Reports, 2017Co-Authors: Daniel G Panaccione, Stephanie L ArnoldAbstract:Neosartorya fumigata (Aspergillus fumigatus) is the most common cause of invasive aspergillosis, a frequently fatal lung disease primarily affecting immunocompromised individuals. This opportunistic fungal pathogen produces several classes of specialised metabolites including products of a branch of the Ergot alkaloid pathway called fumigaclavines. The biosynthesis of the N. fumigata Ergot Alkaloids and their relation to those produced by alternate pathway branches in fungi from the plant-inhabiting Clavicipitaceae have been well-characterised, but the potential role of these Alkaloids in animal pathogenesis has not been studied extensively. We investigated the contribution of Ergot Alkaloids to virulence of N. fumigata by measuring mortality in the model insect Galleria mellonella. Larvae were injected with conidia (asexual spores) of two different wild-type strains of N. fumigata and three different Ergot alkaloid mutants derived by previous gene knockouts and differing in Ergot alkaloid profiles. Elimination of all Ergot Alkaloids significantly reduced virulence of N. fumigata in G. mellonella (P < 0.0001). Mutants accumulating intermediates but not the pathway end product fumigaclavine C also were less virulent than the wild type (P < 0.0003). The data indicate that Ergot Alkaloids contribute to virulence of N. fumigata in this insect model and that fumigaclavine C is important for full virulence.
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Ergot Alkaloids of the family clavicipitaceae
Phytopathology, 2017Co-Authors: Simona Florea, Daniel G Panaccione, Christopher L SchardlAbstract:Ergot Alkaloids are highly diverse in structure, exhibit diverse effects on animals, and are produced by diverse fungi in the phylum Ascomycota, including pathogens and mutualistic symbionts of plants. These mycotoxins are best known from the fungal family Clavicipitaceae and are named for the Ergot fungi that, through millennia, have contaminated grains and caused mass poisonings, with effects ranging from dry gangrene to convulsions and death. However, they are also useful sources of pharmaceuticals for a variety of medical purposes. More than a half-century of research has brought us extensive knowledge of Ergot-alkaloid biosynthetic pathways from common early steps to several taxon-specific branches. Furthermore, a recent flurry of genome sequencing has revealed the genomic processes underlying Ergot-alkaloid diversification. In this review, we discuss the evolution of Ergot-alkaloid biosynthesis genes and gene clusters, including roles of gene recruitment, duplication and neofunctionalization, as wel...
Sarah De Saeger - One of the best experts on this subject based on the ideXlab platform.
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Aptamer-Based Extraction of Ergot Alkaloids from Ergot Contaminated Rye Feed
Advances in Bioscience and Biotechnology, 2014Co-Authors: Elsa Rouah-martin, Walid Maho, Jaytry Mehta, Bieke Van Dorst, Adrian Covaci, Sarah De Saeger, Ronny Blust, Johan RobbensAbstract:Ergot Alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a contamination of plants by fungi of the genus Claviceps. The ingestion of Ergot contaminated cereal crops can lead to a severe poisoning known as Ergotism. For food and feed safety purposes, the extraction of Ergot Alkaloids from Ergot contaminated flour was investigated. For the specific recognition of Ergot Alkaloids, DNA aptamer ligands specially selected for Ergot Alkaloids were grafted onto silica gel in order to construct a specific solid phase extraction system. The aptamer-functionalized silica gels were used to extract Ergot Alkaloids from a contaminated rye feed sample. The presence of Ergot Alkaloids eluted from the aptamer-functionalized silica gels was analyzed using LC-QTOF-MS. By using this simple system, it was possible to specifically extract ergosine, ergokryptine and ergocornine from an Ergot contaminated rye feed sample. This aptamer-based extraction tool shows the applicability of aptamers for the specific extraction of toxins or natural compounds from turbid matrices in a one-step procedure.
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Aptamer-Based Extraction of Ergot Alkaloids from Ergot Contaminated Rye Feed
2014Co-Authors: Elsa Rouah-martin, Walid Maho, Jaytry Mehta, Adrian Covaci, Sarah De Saeger, Ronny Blust, Bieke Van Dorst, Johan RobbensAbstract:Ergot Alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a con-tamination of plants by fungi of the genus Claviceps. The ingestion of Ergot contaminated cereal crops can lead to a severe poisoning known as Ergotism. For food and feed safety purposes, the extraction of Ergot Alkaloids from Ergot contaminated flour was investigated. For the specific recog-nition of Ergot Alkaloids, DNA aptamer ligands specially selected for Ergot Alkaloids were grafted onto silica gel in order to construct a specific solid phase extraction system. The aptamer-func-tionalized silica gels were used to extract Ergot Alkaloids from a contaminated rye feed sample. The presence of Ergot Alkaloids eluted from the aptamer-functionalized silica gels was analyzed using LC-QTOF-MS. By using this simple system, it was possible to specifically extract ergosine, ergo
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Holistic approach based on high resolution and multiple stage mass spectrometry to investigate Ergot Alkaloids in cereals.
Talanta, 2013Co-Authors: Natalia Arroyo-manzanares, Svetlana V. Malysheva, J. Diana Di Mavungu, Julie Vanden Bussche, Lynn Vanhaecke, Sarah De SaegerAbstract:A holistic approach based on high resolution and multiple stage mass spectrometry was developed for identification of less studied or novel Ergot alkaloid derivatives. Initially, the fragmentation of nine known Ergot Alkaloids was studied to establish a strategy for the identification of novel Ergot Alkaloids. Ions with m/z 223 and m/z 251 were found to be common for all ergopeptines, ergoamides and ergopeptams. Subsequently, parent scan experiments using these ions were performed to screen grain samples for the presence of possible Ergot alkaloid derivatives. Besides the six most common Ergot Alkaloids and their corresponding epimers (for which reference standards were available), eleven other Ergot alkaloid derivatives were identified following the proposed strategy.
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Rapid and sensitive LC-MS/MS determination of Ergot Alkaloids in buffered solutions: application to in vitro testing of a clay-based mycotoxin binder
World Mycotoxin Journal, 2013Co-Authors: Svetlana V. Malysheva, Daria Larionova, J. Diana Di Mavungu, Elke Schoeters, Irina Yu. Goryacheva, Sarah De SaegerAbstract:A rapid liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the determination of Ergot Alkaloids in buffered solutions from in vitro studies. The method implied a liquid-liquid extraction of the analytes under alkaline conditions prior to LC-MS/MS analysis and resulted in good recovery (91-123%) of the six Ergot Alkaloids defined by the European Food Safety Authority as most important, namely ergometrine, ergosine, Ergotamine, ergocornine, ergokryptine and ergocristine, as well as their corresponding epimers. The method also proved to be sensitive, repeatable, linear, accurate and robust. Furthermore, the method was applied to evaluate the in vitro binding efficacy of a clay-based mycotoxin binder towards ergometrine, ergosine and ergocornine, through a design encompassing pH 3.0 and 6.8 to mimic the digestive tract. The binder demonstrated binding efficacy of 24, 93 and 97%, respectively, for these Ergot Alkaloids.
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Aptamer-based molecular recognition of lysergamine, metergoline and small Ergot Alkaloids
International journal of molecular sciences, 2012Co-Authors: Elsa Rouah-martin, Jaytry Mehta, Sarah De Saeger, Bieke Van Dorst, Peter Dubruel, Bert U. W. Maes, Filip Lemière, Erik Goormaghtigh, Devin Daems, Wouter A. HerreboutAbstract:Ergot Alkaloids are mycotoxins produced by fungi of the genus Claviceps, which infect cereal crops and grasses. The uptake of Ergot alkaloid contaminated cereal products can be lethal to humans and animals. For food safety assessment, analytical techniques are currently used to determine the presence of Ergot Alkaloids in food and feed samples. However, the number of samples which can be analyzed is limited, due to the cost of the equipment and the need for skilled personnel. In order to compensate for the lack of rapid tests for the detection of Ergot Alkaloids, the aim of this study was to develop a specific recognition element for Ergot Alkaloids, which could be further applied to produce a colorimetric reaction in the presence of these toxins. As recognition elements, single-stranded DNA ligands were selected by using an iterative selection procedure named SELEX, i.e., Systematic Evolution of Ligands by EXponential enrichment. After several selection cycles, the resulting aptamers were cloned and sequenced. A surface plasmon resonance analysis enabled determination of the dissociation constants of the complexes of aptamers and lysergamine. Dissociation constants in the nanomolar range were obtained with three selected aptamers. One of the selected aptamers, having a dissociation constant of 44 nM, was linked to gold nanoparticles and it was possible to produce a colorimetric reaction in the presence of lysergamine. This system could also be applied to small Ergot Alkaloids in an Ergot contaminated flour sample.
T Tobin - One of the best experts on this subject based on the ideXlab platform.
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fragmentation patterns of selected Ergot Alkaloids by electrospray ionization tandem quadrupole mass spectrometry
Journal of Mass Spectrometry, 2004Co-Authors: A F Lehner, Lowell P. Bush, Morrie Craig, Neil Fannin, T TobinAbstract:Tall fescue toxicosis and other maladies in livestock result from the ingestion of vasoconstrictive Ergot Alkaloids produced by fungal endophytes associated symbiotically with the grass. In order to facilitate future analyses of grass extracts considered responsible for outbreak of related livestock diseases, we examined the electrospray ionization mass spectra of specific Ergot Alkaloids under conditions that permit protonation. Our purposes were both to record the spectra with interpretation of mechanisms of fragmentation and to derive commonalities that would allow the prediction of mass spectra of related compounds for which standards were not readily available. With [M + H]+ values in parentheses, water-insoluble lysergic acid peptide Ergot derivatives ergovaline (m/z 534), Ergotamine (m/z 582), ergocornine (m/z 562), ergocryptine (m/z 576) and ergocrystine (m/z 610) exhibited a consistent loss of water (−18 u) from the C-12′ α-hydroxy functionality. Of this group, ergovaline and Ergotamine generated an m/z 320 fragment deriving from cleavage of ring E amide and ether functions with retention of the peptide ring system methyl group. Ergocornine, ergocryptine and ergocrystine similarly formed an m/z 348 fragment with retention of isopropyl. These assignments were supported by the lack of similar fragments from the water-soluble Ergot ergonovine, which lacks a peptide ring system. Clavine-type Ergot Alkaloids lysergic acid and lysergol lack any substituents beyond simple ones directly on the C-8 position and, similarly to ergonovine, lack significant fragments at m/z 268, 251 and 225 shared by the peptide Ergot Alkaloids. Copyright © 2004 John Wiley & Sons, Ltd.
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fragmentation patterns of selected Ergot Alkaloids by electrospray ionization tandem quadrupole mass spectrometry
Journal of Mass Spectrometry, 2004Co-Authors: A F Lehner, Lowell P. Bush, Morrie Craig, Neil Fannin, T TobinAbstract:Tall fescue toxicosis and other maladies in livestock result from the ingestion of vasoconstrictive Ergot Alkaloids produced by fungal endophytes associated symbiotically with the grass. In order to facilitate future analyses of grass extracts considered responsible for outbreak of related livestock diseases, we examined the electrospray ionization mass spectra of specific Ergot Alkaloids under conditions that permit protonation. Our purposes were both to record the spectra with interpretation of mechanisms of fragmentation and to derive commonalities that would allow the prediction of mass spectra of related compounds for which standards were not readily available. With [M + H](+) values in parentheses, water-insoluble lysergic acid peptide Ergot derivatives ergovaline (m/z 534), Ergotamine (m/z 582), ergocornine (m/z 562), ergocryptine (m/z 576) and ergocrystine (m/z 610) exhibited a consistent loss of water (-18 u) from the C-12' alpha-hydroxy functionality. Of this group, ergovaline and Ergotamine generated an m/z 320 fragment deriving from cleavage of ring E amide and ether functions with retention of the peptide ring system methyl group. Ergocornine, ergocryptine and ergocrystine similarly formed an m/z 348 fragment with retention of isopropyl. These assignments were supported by the lack of similar fragments from the water-soluble Ergot ergonovine, which lacks a peptide ring system. Clavine-type Ergot Alkaloids lysergic acid and lysergol lack any substituents beyond simple ones directly on the C-8 position and, similarly to ergonovine, lack significant fragments at m/z 268, 251 and 225 shared by the peptide Ergot Alkaloids.
George E. Seidel - One of the best experts on this subject based on the ideXlab platform.
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effects of Ergot Alkaloids on food preference and satiety in rabbits as assessed with gene knockout endophytes in perennial ryegrass lolium perenne
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Daniel G Panaccione, Caroline Machado, Christopher L Schardl, Jessica R Cipoletti, Andrea B Sedlock, Kenneth P Blemings, George E. SeidelAbstract:Neotyphodium species are fungal endophytes best known for their protection of grass hosts and production of bioactive metabolites including Ergot Alkaloids. Perennial ryegrass−Neotyphodium sp. Lp1 symbiota that have altered Ergot alkaloid profiles (resulting from knockouts in two different endophyte genes) were fed, along with controls, to rabbits to test the effects of Ergot Alkaloids on food preference and satiety. Interestingly, rabbits dramatically preferred plants that were endophyte-infected but free of Ergot Alkaloids over endophyte-free plants (P = 0.01). Accumulation of Ergot Alkaloids of the clavine class counteracted the added appeal of endophyte-infected plants. In satiety tests, consumption of ergovaline (the ultimate Ergot pathway product in wild-type endophyte), but not of several other Ergot Alkaloids, during an initial meal had a negative effect on subsequent rabbit chow consumption (P < 0.05). The data indicate that clavines were sufficient to reduce the appeal of endophyte-infected gras...
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effects of Ergot Alkaloids on food preference and satiety in rabbits as assessed with gene knockout endophytes in perennial ryegrass lolium perenne
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Daniel G Panaccione, Caroline Machado, Christopher L Schardl, Jessica R Cipoletti, Andrea B Sedlock, Kenneth P Blemings, George E. SeidelAbstract:Neotyphodium species are fungal endophytes best known for their protection of grass hosts and production of bioactive metabolites including Ergot Alkaloids. Perennial ryegrass-Neotyphodium sp. Lp1 symbiota that have altered Ergot alkaloid profiles (resulting from knockouts in two different endophyte genes) were fed, along with controls, to rabbits to test the effects of Ergot Alkaloids on food preference and satiety. Interestingly, rabbits dramatically preferred plants that were endophyte-infected but free of Ergot Alkaloids over endophyte-free plants (P = 0.01). Accumulation of Ergot Alkaloids of the clavine class counteracted the added appeal of endophyte-infected plants. In satiety tests, consumption of ergovaline (the ultimate Ergot pathway product in wild-type endophyte), but not of several other Ergot Alkaloids, during an initial meal had a negative effect on subsequent rabbit chow consumption (P < 0.05). The data indicate that clavines were sufficient to reduce the appeal of endophyte-infected grasses, whereas only ergovaline reduced appetite.
Colin Crews - One of the best experts on this subject based on the ideXlab platform.
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Analysis of Ergot Alkaloids
Toxins, 2015Co-Authors: Colin CrewsAbstract:The principles and application of established and newer methods for the quantitative and semi-quantitative determination of Ergot Alkaloids in food, feed, plant materials and animal tissues are reviewed. The techniques of sampling, extraction, clean-up, detection, quantification and validation are described. The major procedures for Ergot alkaloid analysis comprise liquid chromatography with tandem mass spectrometry (LC-MS/MS) and liquid chromatography with fluorescence detection (LC-FLD). Other methods based on immunoassays are under development and variations of these and minor techniques are available for specific purposes.
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Ergot Alkaloids in some rye-based UK cereal products.
Food Additives & Contaminants Part B-surveillance, 2009Co-Authors: Colin Crews, W.a.c. Anderson, G. Rees, Rudolf KrskaAbstract:UK rye-based cereal products were analysed for six major Ergot Alkaloids using an in-house-validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method that distinguished -ine and -inine epimers (isomers). Ergot Alkaloids were detected in 25 of 28 samples subject to quantification limits of 1–3 µg kg−1, including all of eleven rye crispbreads that had up to 340 µg kg−1. Continental-style rye breads contained up to 121 µg kg−1. Loaf breads, bread-mix flours, and crackers contained only low levels of Alkaloids. Ergotamine, ergocristine, and ergosine were the predominant Ergot Alkaloids in terms of level and frequency of occurrence. There were no apparent differences in the Ergot levels between the organic and non-organic products, although the numbers tested were low. Most rye breads had a ratio of -ines to -inines of about 1.5, and rye crispbreads had lower and more variable -ine to -inine ratios.
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Determination of Ergot Alkaloids: purity and stability assessment of standards and optimization of extraction conditions for cereal samples.
Journal of AOAC International, 2008Co-Authors: Rudolf Krska, Franz Berthiller, Rainer Schuhmacher, Kristian Fog Nielsen, Colin CrewsAbstract:Results obtained from a purity study on standards of the 6 major Ergot Alkaloids ergometrine, Ergotamine, ergosine, ergocristine, ergocryptine, and ergocornine and their corresponding epimers are discussed. The 6 Ergot Alkaloids studied have been defined by the European Food Safety Authority as those that are the most common and physiologically active. The purity of the standards was investigated by means of liquid chromatography with diode array detection, electrospray ionization, and time-of-flight mass spectrometry (LC-DAD-ESI-TOF-MS). All of the standards assessed showed purity levels considerably above 98% apart from ergocristinine (94%), ergosine (96%), and ergosinine (95%). Also discussed is the optimization of extraction conditions presented in a recently published method for the quantitation of Ergot Alkaloids in food samples using solid-phase extraction with primary secondary amine (PSA) before LC/MS/MS. Based on the results obtained from these optimization studies, a mixture of acetonitrile with ammonium carbonate buffer was used as extraction solvent, as recoveries for all analyzed Ergot Alkaloids were significantly higher than those with the other solvents. Different sample-solvent ratios and extraction times showed just minor influences in extraction efficacy. Finally, the stability of the Ergot Alkaloids in both raw cereals and cereal-based processed food extracts was studied. According to these studies, extracts should be prepared and analyzed the same day or stored below ambient temperatures. Barley and rye extracts, which were stored at 4 and 15 degrees C after PSA cleanup, proved to be stable overnight. However, storage over a period of 14 days at 4 degrees C resulted in significant epimerization, which was most pronounced in rye and particularly for ergocornine, ergocryptine, and ergocristine.
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simultaneous determination of six major Ergot Alkaloids and their epimers in cereals and foodstuffs by lc ms ms
Analytical and Bioanalytical Chemistry, 2008Co-Authors: Rudolf Krska, George Stubbings, Roy Macarthur, Colin CrewsAbstract:This paper describes a new and rapid method for accurate quantification of the six Ergot Alkaloids, ergometrine, Ergotamine, ergosine, ergocristine, ergocryptine, and ergocornine, by liquid chromatography–tandem mass spectrometry (LC–MS–MS). The six Ergot Alkaloids studied have been defined by the European Food Safety Authority (EFSA) as among the most common and physiologically active ones. In addition, the method enables the quantification of the corresponding six epimers (ergo-inines) of these Ergot Alkaloids. This is of considerable importance in terms of the differences in toxicity of the isomeric forms. The method involves extraction under alkaline conditions using a mixture of acetonitrile and ammonium carbonate buffer followed by a rapid clean-up using dispersive solid-phase extraction with PSA (primary secondary amine) and a short chromatographic LC-run (21 min) with subsequent MS–MS detection. The method was developed and validated using ten different cereal and food samples. The major strength of the new method compared with previously published techniques is the simplicity of the clean-up procedure and the short analysis time. The limits of quantification were 0.17 to 2.78 μg kg−1 depending on the analyte and matrix. Recovery values for the 12 Ergot Alkaloids spiked into ten different matrices at levels of 5, 50, and 100 μg kg−1 were between 69 and 105% for 85 of 90 recovery measurements made over six days. Measurement uncertainty values were highly satisfactory. At a concentration level of 5 μg kg−1 the expanded measurement uncertainty ranged from ±0.56 to ±1.49 μg kg−1, at a concentration level of 100 μg kg−1 the expanded measurement uncertainty ranged from ±8.9 to ±20 μg kg−1. Both LOQs and measurement uncertainties were dependent on the analyte but almost independent of the matrix. The method performance was satisfactory when tested in a mini-intercomparison study between three laboratories from three different countries.
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Stability and epimerisation behaviour of Ergot Alkaloids in various solvents
World Mycotoxin Journal, 2008Co-Authors: M. Hafner, Rainer Schuhmacher, Colin Crews, Michael Sulyok, Rudolf KrskaAbstract:In this paper the stability and degree of epimerisation of six major Ergot Alkaloids at three different temperature levels (-20 °C, +4 °C and +20 °C) over periods of 18 hours and six weeks is reported for the first time. The behaviour of ergometrine, ergocornine, ergocristine, α-ergocryptine, ergosine and Ergotamine was thoroughly studied in seven solvents which are employed for the preparation of calibrants and extraction mixtures, respectively. Moreover, the stability of the Ergot Alkaloids was tested in different cereal extracts (rye, wheat, barley, oats) for 1, 2 and 6 days. Of the toxins tested, the ergopeptide-type toxins ergosine, Ergotamine, ergocornine, α-ergocryptine and ergocristine showed similar behaviour patterns. The simple lysergic acid derivative ergometrine was more stable and showed hardly any epimerisation to ergometrinine, with the sum of both epimers remaining constant in all seven solvents. The ergopeptides tested show variable epimerisation tendencies, and were also less stable dur...