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1.
Toxins (Basel) ; 13(5)2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925104

RESUMO

The natural occurrence of six major ergot alkaloids, ergometrine, ergosine, ergotamine, ergocornine, ergokryptine and ergocristine, as well as their corresponding epimers, were investigated in 60 cereal samples (barley and wheat) from Algeria. Ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) and a QuEChERS extraction method were used for sample analysis. The results revealed that 12 out of 60 samples (20%) were contaminated with ergot alkaloids. Wheat was the most contaminated matrix, with an incidence of 26.7% (8 out of 30 samples). The concentration of total ergot alkaloids ranged from 17.8 to 53.9 µg/kg for barley and from 3.66 to 76.0 µg/kg for wheat samples. Ergosine, ergokryptine and ergocristine showed the highest incidences in wheat, while ergometrine was the most common ergot in barley.


Assuntos
Alcaloides de Claviceps/análise , Hordeum/química , Triticum/química , Argélia , Cromatografia Líquida de Alta Pressão , Ergolinas/análise , Ergonovina/análise , Ergotamina/análise , Ergotaminas/análise , Microbiologia de Alimentos , Limite de Detecção , Espectrometria de Massas em Tandem
2.
Artigo em Inglês | MEDLINE | ID: mdl-33784227

RESUMO

Cereals and feed contaminated with ergot alkaloids (EAs) have been of concern for several decades. Nowadays, analysis of EAs is focused on ergometrine, ergotamine, ergosine, ergocristine, ergocryptine (a mixture of α- and ß-isomers) and ergocornine and their related -inine epimers as listed in the European Commission Recommendation 2012/154/EU. Liquid chromatography with fluorescence detection has been used for quantification of EAs for decades whilst LC-MS has become the work-horse for quantification of EAs in the last decade. However, in LC-MS analysis matrix effects of different magnitudes exist for each EA epimer, especially ergometrine/ergometrinine, even after different clean-up procedures. This leads to an underestimation or overestimation of EAs levels. Moreover, isotopic labelled standards for EAs are still not available in the market. This review aims to provide background information on different analytical methods, discuss their advantages and disadvantages and possible advancement. Moreover, the method performance requirements to support forthcoming regulations are also discussed.


Assuntos
Grão Comestível/química , Alcaloides de Claviceps/análise , Contaminação de Alimentos/análise , Toxinas Biológicas/análise , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Ergolinas/análise , Ergotaminas/análise , Humanos , Lipídeos/química , Espectrometria de Fluorescência , Espectrometria de Massas em Tandem
3.
Plant Dis ; 102(7): 1334-1340, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30673578

RESUMO

In the present study, the genetic relationships and ergot-alkaloid production of the fungus Claviceps purpurea on grasses were investigated, to determine any associations between grass host specificity, ergot-alkaloid production, and geographic origin. C. purpurea sclerotia were obtained from wild and cultivated grasses along a 300-km climatic gradient, from sub-Mediterranean to continental climates. Twenty-one infected grass samples provided 39 sclerotia for analysis of the ergot alkaloids ergometrine, ergosine, ergotamine, ergocornine, ergocryptine, and ergocristine, and their "-inine" epimers, using liquid chromatography-tandem mass spectrometry. C. purpurea ribosomal DNA underwent molecular classification to determine any grass host or geographic specificity of ergot-alkaloid composition for the different operational taxonomic units. Molecular analysis of sclerotia ribosomal DNA showed three genetic groups, with some associations with specific grass host taxonomic groups. The ergot-alkaloid composition data were in agreement with the data obtained by molecular methods. The most frequent ergot-alkaloid epimers were ergocristine, and ergosine. The total ergot-alkaloid concentrations in sclerotia varied from 59 to 4,200 mg kg-1, which corresponds to 0.059 to 4.2 mg kg-1 in animal feed (assuming ergot alkaloids at 1,000 mg kg-1 sclerotia). Therefore, grasses can be associated with significant levels of ergot alkaloids. In addition, the ergot-alkaloid compositions of C. purpurea sclerotia can be different for infections with different C. purpurea genetic groups, because these show different ergot-alkaloid compositions.


Assuntos
Claviceps/química , Alcaloides de Claviceps/análise , Doenças das Plantas/microbiologia , Poaceae/microbiologia , Cromatografia Líquida de Alta Pressão , Claviceps/classificação , Claviceps/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Ergolinas/análise , Ergonovina/análise , Ergotamina/análise , Ergotaminas/análise , Especificidade de Hospedeiro , Filogenia , Análise de Sequência de DNA , Eslovênia , Espectrometria de Massas em Tandem
4.
J AOAC Int ; 99(4): 895-898, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27455930

RESUMO

Ergot is a common disease of wheat and other cereal grains that is predominantly caused by Claviceps purpurea in the field, often affecting crop yield in addition to the environment. Infected grain can be contaminated with dark sclerotia, which contain fungal metabolites such as ergot alkaloids. The occurrence of ergot alkaloids in cereal grain is a major health concern for humans and livestock. Effective and rapid screening of these mycotoxins is crucial for producers, processors, and consumers of cereal-based food and feed grain. Established methods of ergot alkaloid screening based on LC-MS or GC-MS require laborious processes. A novel method using matrix-assisted laser desorption ionization (MALDI)-time-of-flight (TOF) MS was developed to identify four ergot alkaloids. Using dihydroxybenzoic acid as the matrix, ergosine, ergocornine, ergocryptine, and ergocristine were readily detected in individual sclerotia of C. purpurea. The accuracy of the identified ergot alkaloids was further confirmed by tandem MS analysis. MALDI-TOF MS is suitable for high-throughput screening of ergot alkaloids because it permits rapid and accurate identification, simple sample preparation, and no derivatization or chromatographic separation.


Assuntos
Claviceps/química , Alcaloides de Claviceps/análise , Ergolinas/análise , Ergotaminas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem/métodos
5.
J Chromatogr A ; 1441: 126-33, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-26947163

RESUMO

The analysis of ergot alkaloids is generally performed by high-performance liquid chromatography (HPLC) coupled to fluorescence detection (FLD) or mass selective detection. As for monitoring only the sum of ergot alkaloids is relevant, a fast and easy screening method for the determination of the total alkaloid content was developed using planar solid phase extraction (pSPE). Applying pSPE, recently introduced for pesticide residue analysis in fruits and vegetables (Oellig and Schwack, 2011) and tea (Oellig and Schwack, 2012), all ergot alkaloids are concentrated in a target zone followed by detection as the sum. The herein presented method includes an ammonium acetate buffered extraction step, followed by a fast liquid-liquid partitioning pre-cleaning before pSPE is performed on high-performance thin-layer chromatography (HPTLC) amino plates with a single methanol development to separate the ergot alkaloids from the remaining matrix and to collect them in a single zone. For quantitation, the native fluorescence was used after dipping the plate in n-hexane/paraffin solution for fluorescence enhancement. Limits of detection and quantitation of 0.07 and 0.24 mg/kg rye, respectively, expressed as ergocristine, were well below the currently applied quality criterion limit for rye. Near-100% recoveries were obtained at relevant spiking levels for different rye flour samples. Hence, the fast pSPE-FLD is an efficient and reliable method to screen for the total ergot alkaloid content in rye and a rapid alternative to the HPLC determination of individual alkaloids and to summing them up. HPTLC-MS additionally enables the identification of the ergot alkaloid composition by a single mass spectrum, when utilized as a fingerprint, offering an easy differentiation of Secale cornutum from different origins.


Assuntos
Alcaloides de Claviceps/análise , Farinha/análise , Secale/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Ergolinas/análise , Fluorescência , Espectrometria de Massas , Extração em Fase Sólida
6.
J Chem Ecol ; 41(1): 93-104, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25501262

RESUMO

Epichloid endophytes are well known symbionts of many cool-season grasses that may alleviate environmental stresses for their hosts. For example, endophytes produce alkaloid compounds that may be toxic to invertebrate or vertebrate herbivores. Achnatherum robustum, commonly called sleepygrass, was aptly named due to the presence of an endophyte that causes toxic effects to livestock and wildlife. Variation in alkaloid production observed in two A. robustum populations located near Weed and Cloudcroft in the Lincoln National Forest, New Mexico, suggests two different endophyte species are present in these populations. Genetic analyses of endophyte-infected samples revealed major differences in the endophyte alkaloid genetic profiles from the two populations, which were supported with chemical analyses. The endophyte present in the Weed population was shown to produce chanoclavine I, paspaline, and terpendoles, so thus resembles the previously described Epichloë funkii. The endophyte present in the Cloudcroft population produces chanoclavineI, ergonovine, lysergic acid amide, and paspaline, and is an undescribed endophyte species. We observed very low survival rates for aphids feeding on plants infected with the Cloudcroft endophyte, while aphid survival was better on endophyte infected plants in the Weed population. This observation led to the hypothesis that the alkaloid ergonovine is responsible for aphid mortality. Direct testing of aphid survival on oat leaves supplemented with ergonovine provided supporting evidence for this hypothesis. The results of this study suggest that alkaloids produced by the Cloudcroft endophyte, specifically ergonovine, have insecticidal properties.


Assuntos
Alcaloides/análise , Afídeos/fisiologia , Endófitos/química , Epichloe/química , Herbivoria , Poaceae/química , Animais , Afídeos/efeitos dos fármacos , Epichloe/genética , Ergolinas/análise , Ergonovina/análise , Ergonovina/farmacologia , Alcaloides de Claviceps/análise , Variação Genética , Indóis/análise , Inseticidas/farmacologia , Dietilamida do Ácido Lisérgico/análogos & derivados , Dietilamida do Ácido Lisérgico/análise , New Mexico , Poaceae/microbiologia , Poaceae/fisiologia
7.
Biomed Chromatogr ; 26(9): 1096-100, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22120837

RESUMO

A rapid, simple, sensitive, gradient and reproducible, reverse-phase high-performance liquid chromatographic method was developed for the quantitative estimation of bioactive alkaloids, lysergol and chanoclavine in the seeds of Ipomoea muricata. The clavine alkaloid, lysergol, is a bioenhancer for the drugs and nutrients. The samples were analyzed by reverse-phase chromatography on a Waters spherisorb ODS2 column (250 × 4.6 mm, i.d., 10 µm) using binary gradient elution with acetonitrile and 0.01 m phosphate buffer (NaH2PO4) containing 0.1% glacial acetic acid at a flow rate of 0.8 mL/min, a column temperature of 25 °C and UV detection at λ 254 nm. The limits of detection (LOD) and quantitation (LOQ) were 0.035 and 0.106 µg/mL for lysergol and 0.039 and 0.118 µg/mL for chanoclavine, respectively. Standard curves were linear in the range of 2-10 µg/mL (r > 99) for both analytes. Good results were achieved with respect to repeatability (RSD < 2%) and recovery (99.20-102.0). The method was validated for linearity, accuracy repeatability, LOQ and LOD. The method is simple, accurate and precise, and may be recommended for routine quality control analysis of I. muricata seed extracts containing these two clavine alkaloids (1, 2) as bioactive principles of the herb.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Ergolinas/análise , Ipomoea/química , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes , Sementes/química , Sensibilidade e Especificidade
8.
Prikl Biokhim Mikrobiol ; 47(3): 318-23, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21790032

RESUMO

Screening of producers of secondary metabolites was carried out among 25 fungal strains of Penicillium genus isolated from permafrost in Arctic and Antarctic regions and Kamchatka. Nearly 50% of the investigated strains synthesize biologically active substances of alkaloid nature: ergot alkaloids, diketopiperazines, and quinoline derivatives. A large group of the identified metabolites belongs to mycotoxins. A strain of Penicillium waksmanii was found producing epoxiagroclavine-I and quinocitrinins. The main physiological and biochemical characteristics of this producer were investigated.


Assuntos
Dicetopiperazinas/metabolismo , Ergolinas/metabolismo , Micotoxinas/biossíntese , Penicillium , Quinolinas/metabolismo , Regiões Antárticas , Regiões Árticas , Cromatografia em Camada Fina , Temperatura Baixa , Dicetopiperazinas/análise , Ergolinas/análise , Técnicas de Tipagem Micológica , Micotoxinas/análise , Penicillium/química , Penicillium/isolamento & purificação , Penicillium/metabolismo , Quinolinas/análise , Espectrofotometria Ultravioleta
9.
Artigo em Inglês | MEDLINE | ID: mdl-18774762

RESUMO

The UPLC method with diode array UV detection was developed for qualitative determination of ergocristine and ergocristam including degradation products. The mechanism of the ergocristam disruptive reaction was described based on MS/MS characterization of ammonolytic product, N-(d-lysergyl)-l-valinamide (A1) and two methanolytic products, methyl ester of N-(d-lysergyl)-l-valine (M2), and N-[N-(d-lysergyl)-l-valyl]-l-phenylalanyl-d-prolyl methyl ester (M1). The influence of extraction conditions on epimerization and degradation of ergocristine and ergocristam was tested and conditions for reproducible decomposition of ergocristam were found. The presented method could potentially be applied for ergot alkaloids determination in sclerotia, fermentation broth, mycelium, and possibly contaminated food products, i.e. corn, flour, bread, etc., and feeding stuffs containing ungrounded cereals.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ergolinas/análise , Alcaloides de Claviceps/análise , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Ergolinas/química , Ergolinas/isolamento & purificação , Alcaloides de Claviceps/química , Alcaloides de Claviceps/isolamento & purificação
10.
Artigo em Inglês | MEDLINE | ID: mdl-18311624

RESUMO

Ergot alkaloids are mycotoxins that are undesirable contaminants of cereal products, particularly rye. A method was developed employing clean-up by cation-exchange solid-phase extraction, separation by high-performance liquid chromatography under alkaline conditions and fluorescence detection. It is capable of separating and quantifying both C8-isomers of ergocornine, alpha-ergocryptine, ergocristine, ergonovine, and ergotamine. The average recovery was 61% +/- 10% with limits of detection from 0.2 to 1.1 microg kg(-1). Twenty-four unknown rye flour samples from Danish mills contained on average 46 microg kg(-1) with a maximum content of 234 microg kg(-1). The most common ergot alkaloids were ergotamine and alpha-ergocryptine including their C8-isomers. A total of 54% of the ergot alkaloids were detected as C(8)-S isomers.


Assuntos
Alcaloides de Claviceps/análise , Contaminação de Alimentos/análise , Secale , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Dinamarca , Ergolinas/análise , Ergonovina/análise , Ergotamina/análise , Farinha/análise , Espectrometria de Fluorescência
11.
Rapid Commun Mass Spectrom ; 21(10): 1651-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17465016

RESUMO

Ergot alkaloids are mycotoxins which are produced among fungi in the family Clavicipitaceae. Poisoning with ergot alkaloids is an important veterinary problem in animal husbandry and has recently also been recognised in wild animals. While the poisoning syndrome observed in domestic animals such as cattle, horses and sheep is usually caused by endophyte-infected grass, the recently observed ergotism among Norwegian cervids is probably due to infection of wild grasses with Claviceps. Mass spectrometry is today the method of choice for the rapid qualitative and quantitative determination of many natural compounds. This study uses tandem quadrupole mass spectrometry as well as ion trap mass spectrometry in connection with electrospray(+) ionisation for the quantification, screening and fragmentation of ergot alkaloids in extracts from Claviceps sclerotia that had been picked from wild grasses from several locations in Norway. Ergotamine, ergovaline, ergonovine and ergocryptine were available as standards and were quantified in the extracts, while ergocrystine, ergocornine, ergonine/ergosine, lysergic acid and lysergol were identified on the basis of their molecular weights and semi-quantified. Ergocrystine dominated the alkaloid spectrum of most extracts. Levels of the quantified alkaloids were in the range 0.2-9300 microg/g. Several unknown ergot alkaloids were found in the extracts. MS(n) experiments identified some as simple lysergic acid amide derivatives, while othes are probably related to ergocrystine and ergocryptine by dehydration, dehydrogenation and/or amino acid substitution at R(1) of the peptide moiety.


Assuntos
Alcaloides de Claviceps/análise , Poaceae/química , Cromatografia Líquida de Alta Pressão , Claviceps/química , Ergolinas/análise , Ergotamina/análise , Indicadores e Reagentes , Ácido Lisérgico/química , Noruega , Peptídeos/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
12.
Chem Pharm Bull (Tokyo) ; 55(4): 629-31, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17409559

RESUMO

Simple and reproducible spectrophotometric methods have been developed for determination of dopaminergic drugs used for Parkinson's disease, cabergoline (CAB) and ropinirole hydrochloride (ROP), in pharmaceutical preparations. The methods are based on the reactions between the studied drug substances and ion-pair agents [methyl orange (MO), bromocresol green (BCG) and bromophenol blue (BPB)] producing yellow colored ion-pair complexes in acidic buffers, after extracting in dichloromethane, which are spectrophotometrically determined at the appropriate wavelength of ion-pair complexes. Beer's law was obeyed within the concentration range from 1.0 to 35 microg ml(-1). The developed methods were applied successfully for the determination of these drugs in tablets.


Assuntos
Dopaminérgicos/análise , Ergolinas/análise , Indóis/análise , Doença de Parkinson/tratamento farmacológico , Preparações Farmacêuticas/química , Cabergolina , Dopaminérgicos/uso terapêutico , Ergolinas/uso terapêutico , Humanos , Concentração de Íons de Hidrogênio , Indóis/uso terapêutico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Chembiochem ; 7(4): 645-52, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16538694

RESUMO

Clavines and D-lysergic acid-derived alkaloid amides and alkaloid peptides are two different families of compounds that have the indole-derived tetracyclic metergoline ring system in common. Previous work has shown that D-lysergic acid is biosynthetically derived from clavine alkaloids. Recent cloning and analysis of the ergot alkaloid biosynthesis gene cluster from the D-lysergic acid peptide (ergopeptines)-producing Claviceps purpurea, has shown that it most probably contains all genes necessary for D-lysergic acid synthesis as well as those that encode the assembly of D-lysergic acid peptides, such as ergotamine. To address the role of the oxygenase genes of alkaloid-gene clusters, the only cytochrome P450 monooxygenase gene of this cluster was inactivated by disruption. The resultant mutant accumulated agroclavine, elymoclavine, and chanoclavine in substantial amounts but not ergopeptines. Feeding the mutant with D-lysergic acid restored ergopeptine synthesis; this suggests a block in the conversion of elymoclavine to D-lysergic acid. The gene was designated cloA (for encoding a clavine oxidase, CLOA). Retransformation of the mutant with the intact cloA gene also restored ergopeptine synthesis. These data show that CLOA catalyses the conversion of clavines to D-lysergic acid, it acts as a critical enzyme in the ergot alkaloid gene cluster, and bridges the biosynthesis of the two different families of alkaloids.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Ergolinas/metabolismo , Alcaloides de Claviceps/metabolismo , Oxigenases de Função Mista/metabolismo , Claviceps/enzimologia , Claviceps/genética , Sistema Enzimático do Citocromo P-450/análise , Sistema Enzimático do Citocromo P-450/genética , Ergolinas/análise , Alcaloides de Claviceps/análise , Alcaloides de Claviceps/genética , Oxigenases de Função Mista/análise , Oxigenases de Função Mista/genética , Estrutura Molecular , Mutação
14.
J Mass Spectrom ; 39(11): 1275-86, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15470699

RESUMO

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.


Assuntos
Alcaloides de Claviceps/análise , Alcaloides de Claviceps/química , Festuca/microbiologia , Doenças dos Cavalos/etiologia , Espectrometria de Massas por Ionização por Electrospray , Ração Animal , Animais , Ergolinas/análise , Ergolinas/química , Ergonovina/análise , Ergonovina/química , Ergotamina/análise , Ergotamina/química , Ergotaminas/análise , Ergotaminas/química , Contaminação de Alimentos , Cavalos , Ácido Lisérgico/análise , Ácido Lisérgico/química
15.
Planta ; 219(4): 619-25, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15085432

RESUMO

Ergoline alkaloids are constituents of Clavicipitaceous fungi living on Poaceae plants. Ergoline alkaloids as well as volatile oil are also present in Ipomoea asarifolia Roem. & Schult (Convolvulaceae). Treatment of this plant with two fungicides (Folicur, Pronto Plus) eliminates the ergoline alkaloids but not the volatile oil. Elimination of ergoline alkaloids occurs concomitantly with loss of fungal hyphae associated with secretory glands on the upper leaf surface of the Ipomoea plant. Our observations suggest that accumulation of ergoline alkaloids in the Convolvulaceae may depend on the presence of a plant-associated fungus.


Assuntos
Ergolinas/análise , Fungicidas Industriais/farmacologia , Ipomoea/efeitos dos fármacos , Ergolinas/química , Ipomoea/química , Modelos Químicos , Óleos Voláteis/análise , Óleos Voláteis/química , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Triazóis/farmacologia
16.
Mikrobiologiia ; 72(6): 816-21, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14768549

RESUMO

The study of the secondary metabolites of the relict strain Penicillium citrinum VKM FW-800 isolated from ancient Arctic permafrost sediments showed that this fungus produces agroclavine-1 and epoxyagroclavine-1, which are rare ergot alkaloids with the 5R,10S configuration of the tetracyclic ergoline ring system. The production of the alkaloids by the fungus showed a biphasic behavior, being intense in the phase of active growth and slowing down in the adaptive lag phase and in the stationary growth phase. The addition of zinc ions to the incubation medium led to a fivefold increase in the yield of the alkaloids. The alkaloids-producing Penicillium fungi isolated from different regions exhibited the same tendencies of growth and alkaloid production.


Assuntos
Ergolinas/metabolismo , Sedimentos Geológicos/microbiologia , Penicillium/metabolismo , Regiões Árticas , Ergolinas/análise , Penicillium/crescimento & desenvolvimento , Penicillium/isolamento & purificação
17.
J Am Vet Med Assoc ; 221(10): 1441-4, 1420, 2002 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-12458614

RESUMO

Mycotoxins are fungal metabolites that induce undesirable effects. The effects of these mycotoxins vary depending on the chemical structure of the toxin and degree of toxicity. Mycotoxins that induce muscle tremors, ataxia, and convulsions are termed tremorgenic mycotoxins. Our report documents the clinical course of 4 dogs from a single household that were simultaneously affected by tremorgenic mycotoxins. Diagnosis of tremorgenic mycotoxicosis was confirmed by stomach content analysis from 1 of the dogs. The mycotoxins identified were penitrem A and roquefortine, which are both produced by Penicillium spp. Treatment goals following tremorgenic mycotoxin ingestion include minimizing absorption, controlling tremors and seizures with methocarbamol and pentobarbital sodium administration, and providing supportive care. Two of the affected dogs required ventilatory support. With early aggressive treatment, prognosis is good and recovery is complete without sequelae. It is helpful for the clinician to be familiar with the typical clinical signs at the time of admission, treatment, and clinical course of dogs with tremorgenic mycotoxicosis.


Assuntos
Doenças do Cão/induzido quimicamente , Indóis , Micotoxicose/veterinária , Micotoxinas/intoxicação , Tremor/veterinária , Animais , Ataxia/induzido quimicamente , Ataxia/terapia , Ataxia/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/terapia , Cães , Ergolinas/análise , Ergolinas/intoxicação , Conteúdo Gastrointestinal/química , Compostos Heterocíclicos de 4 ou mais Anéis , Masculino , Micotoxicose/complicações , Micotoxicose/terapia , Micotoxinas/análise , Piperazinas , Convulsões/induzido quimicamente , Convulsões/diagnóstico , Convulsões/terapia , Convulsões/veterinária , Tremor/induzido quimicamente , Tremor/diagnóstico , Tremor/terapia
18.
J Nat Prod ; 65(7): 1039-40, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12141870

RESUMO

Two ergopeptine alkaloids, alpha-ergocryptine (1) and its C(8) epimer alpha-ergocryptinine, have been isolated from the mycelium and fermentation broth of submerged cultures of Claviceps zizaniae CCM 8240. The structure of 1 was determined by HPLC/positive ion APCI MS and NMR analysis. Alkaloid concentrations of 10 microg/mL in 14-day-old fermentation broth and 1 mg/g of dry mycelium mass were found. These results are of considerable biotechnological interest since these were the only detectable alkaloids produced. Toxicity of naturally occurring sclerotia of C. zizaniae cannot be excluded.


Assuntos
Claviceps/química , Claviceps/metabolismo , Ergolinas/isolamento & purificação , Alcaloides de Claviceps/isolamento & purificação , Canadá , Cromatografia Líquida de Alta Pressão , República Tcheca , Ergolinas/análise , Ergolinas/química , Alcaloides de Claviceps/análise , Alcaloides de Claviceps/química , Fermentação , Espectrometria de Massas , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Espectrofotometria Ultravioleta , Estereoisomerismo
19.
Prikl Biokhim Mikrobiol ; 38(1): 35-9, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11852564

RESUMO

Using the induced mutagenesis technique, A series of genetically modified Claviceps sp. VKM F-2609 strains that display high levels of agroclavine and elymoclavine synthesis were selected by induced mutagenesis. Compared to the parent strain, c106 displayed a 40-fold higher level of agroclavine synthesis, and c66 displayed an eightfold higher level of elymoclavine synthesis. The levels of synthesis of other alkaloids were decreased in these strains. The effects of various carbohydrates on the strain growth and ergot alkaloid biosynthesis was then investigated in both the parent strain and c106. The largest amount of agroclavine was synthesized by c106 strain growing on a medium with maltose.


Assuntos
Claviceps/genética , Alcaloides de Claviceps/biossíntese , Mutagênese , Claviceps/crescimento & desenvolvimento , Claviceps/metabolismo , Meios de Cultura , Ergolinas/análise , Ergolinas/metabolismo , Alcaloides de Claviceps/análise , Maltose/metabolismo , Regulação para Cima
20.
Prikl Biokhim Mikrobiol ; 38(1): 40-3, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11852565

RESUMO

Variability in the roquefortine yield was shown to be associated with its consumption by the mycelium during isolation of the end product, which depended on temperature, time of culture liquid storage, and biomass concentration. This was also related to the presence in chloroform of chlorocarbonic acid ethyl ester that reacted with roquefortine.


Assuntos
Ergolinas/metabolismo , Indóis , Micotoxinas/metabolismo , Penicillium/metabolismo , Clorofórmio/química , Ergolinas/análise , Ergolinas/química , Formiatos/química , Compostos Heterocíclicos de 4 ou mais Anéis , Estrutura Molecular , Micélio/metabolismo , Micotoxinas/análise , Penicillium/crescimento & desenvolvimento , Piperazinas , Temperatura , Fatores de Tempo
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