Natural toxins最新文献

Erratum: Alfonso D, Johnson HA, Colman-Saizarbitoria T, Presley CP, McCabe GP, McLaughlin JL (1996): SARs of annonaceous acetogenins in rat liver mitochondria. Nat Toxins 4:181-188. 更正:Alfonso D, Johnson HA, coleman - saizarbitoria T, Presley CP, McCabe GP, McLaughlin JL(1996):大鼠肝脏线粒体中无性系乙酰原素的SARs。Nat Toxins 4:181-188。

Natural toxins Pub Date : 2006-05-30 DOI: 10.1002/(SICI)(1996)4:6<295::AID-NT8>3.0.CO;2-P

D. Alfonso, H. Johnson, T. Colman-saizarbitoria, C. Presley, G. McCabe, J. McLaughlin

引用次数: 1

Advances in detection methods for fungal and algal toxins. 真菌和藻类毒素检测方法的研究进展。

Natural toxins Pub Date : 1999-11-01 DOI: 10.1002/1522-7189(199911/12)7:6<343::aid-nt88>3.0.co;2-#

Van Dolah FM, Richard

引用次数: 3

HPLC/MS analysis of fusarium mycotoxins, fumonisins and deoxynivalenol. 镰刀菌毒素、伏马毒素和脱氧雪腐镰刀菌醇的HPLC/MS分析。

Natural toxins Pub Date : 1999-11-01 DOI: 10.1002/1522-7189(199911/12)7:6<365::AID-NT85>3.0.CO;2-0

R. Plattner

{"title":"HPLC/MS analysis of fusarium mycotoxins, fumonisins and deoxynivalenol.","authors":"R. Plattner","doi":"10.1002/1522-7189(199911/12)7:6<365::AID-NT85>3.0.CO;2-0","DOIUrl":"https://doi.org/10.1002/1522-7189(199911/12)7:6<365::AID-NT85>3.0.CO;2-0","url":null,"abstract":"Fusarium fungi are widely found in agricultural products, worldwide and can produce a great variety of mycotoxins. Fumonisins, produced by F. moniliforme, and deoxynivalenol, produced by F. graminearum, are two such mycotoxins that have received considerable attention as food safety concerns by regulatory agencies. High Performance Liquid Chromatography/Mass Spectrometry (HPLC/MS) was found to be a convenient analytical method to detect and quantify the naturally occurring fumonisin homologs and deoxynivalenol in extracts from grains and food products. The fumonisins are detected primarily as protonated molecules in the positive ion electrospray ionization (ESI) mode as they elute from a C-18 reverse phase column during a methanol water gradient containing acetic acid to facilitate chromatography. Deoxynivalenol can be detected as positive or negative ions in the atmospheric pressure chemical ionization (APCI) mode or in the negative ion ESI mode. One nanogram amounts of fumonisins or deoxynivalenol injected into the HPLC system are easily detected with signal to noise allowing detection limits of 1 microg g(-1) or better to easily be achieved with minimal clean-up of grain extracts.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"104 1","pages":"365-70"},"PeriodicalIF":0.0,"publicationDate":"1999-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87753219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 51

Neuronal binding of tetanus toxin compared to its ganglioside binding fragment (H(c)). 与神经节苷脂结合片段相比，破伤风毒素的神经元结合(H(c))。

Natural toxins Pub Date : 1999-07-01 DOI: 10.1002/(SICI)1522-7189(199907/08)7:4<151::AID-NT51>3.0.CO;2-K

P. Fishman, D. A. Parks, A. Patwardhan, C. C. Matthews

{"title":"Neuronal binding of tetanus toxin compared to its ganglioside binding fragment (H(c)).","authors":"P. Fishman, D. A. Parks, A. Patwardhan, C. C. Matthews","doi":"10.1002/(SICI)1522-7189(199907/08)7:4<151::AID-NT51>3.0.CO;2-K","DOIUrl":"https://doi.org/10.1002/(SICI)1522-7189(199907/08)7:4<151::AID-NT51>3.0.CO;2-K","url":null,"abstract":"The non-toxin 50 kD C-terminus peptide of the heavy chain of tetanus H(c) contains the ganglioside binding domain of tetanus toxin (TTX). H(c) retains much of the capacity of tetanus toxin for binding internalization and transport by neurons. For this reason tetanus H(c) has been studied as a vector for delivery of therapeutic proteins to neurons. We directly compared H(c) and TTX in the capacity to bind and be internalized by neurons by ELISA. Primary cultures of dissociated fetal cortical neurons were incubated with equimolar amounts of TTX or H(c). Neuronal associated tetanus protein was 4-8 fold greater on a molar basis with tetanus toxin compared to H(c) (1 h incubation). This increase in neuronal tetanus protein was evident with incubation in concentrations from 0.1 microM to 2 microM. There were greater amounts of TTX delivered to the cultured cells at both 0 degrees C (representing membrane bound tetanus protein) and 37 degrees C (bound and internalized tetanus protein). Unlike H(c), TTX showed significant continued accumulation of protein with increasing incubation durations. Neuronal associated TTX increased 2-3 fold over incubation times ranging from 1 to 8 h. Tetanus toxin appears to be clearly superior to the ganglioside binding fragment (H(c)) in the capacity for neuronal binding and internalization. Atoxic tetanus proteins containing additional molecular domains as well as H(c) may be more suitable vectors for linkage with therapeutic proteins and delivery to neurons.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"126 1","pages":"151-6"},"PeriodicalIF":0.0,"publicationDate":"1999-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76388993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 14

A new type sandwich immunoassay for microcystin: production of monoclonal antibodies specific to the immune complex formed by microcystin and an anti-microcystin monoclonal antibody. 一种新型的微囊藻毒素夹心免疫测定方法:制备针对微囊藻毒素与抗微囊藻毒素单克隆抗体形成的免疫复合物的特异性单克隆抗体。

Natural toxins Pub Date : 1999-03-01 DOI: 10.1002/(SICI)1522-7189(199903/04)7:2<49::AID-NT43>3.0.CO;2-7

S. Nagata, T. Tsutsumi, F. Yoshida, Y. Ueno

{"title":"A new type sandwich immunoassay for microcystin: production of monoclonal antibodies specific to the immune complex formed by microcystin and an anti-microcystin monoclonal antibody.","authors":"S. Nagata, T. Tsutsumi, F. Yoshida, Y. Ueno","doi":"10.1002/(SICI)1522-7189(199903/04)7:2<49::AID-NT43>3.0.CO;2-7","DOIUrl":"https://doi.org/10.1002/(SICI)1522-7189(199903/04)7:2<49::AID-NT43>3.0.CO;2-7","url":null,"abstract":"To develop an ultrasensitive immunoassay for microcystins (MCs), a group of heptapeptide hepatotoxins produced by cyanobacteria, we produced monoclonal antibodies (MAbs) which specifically recognize the immune complex (IC) formed by an anti-MC MAb (MC MAb) and MCs. The use of the anti-IC MAb (IC MAb) as the secondary antibody made it possible to develop a sandwich type immunoassay, which is theoretically superior to the widely used competitive immunoassay in sensitivity as well as accuracy. A MC MAb mixed with microcystin-LR (MCLR) to form the IC was immunized to mice. Three IC MAbs were obtained, all of which specifically reacted with the IC, but almost never reacted to MC MAb or MCLR in enzyme-linked immunosorbent assays (ELISAs). Binding kinetics study of one of the IC MAbs, 3F7, by a BIAcore biosensor technique revealed that 3F7 IC MAb could associate with free MC MAb as well as the IC, but the binding to free MC MAb was much more easily dissociated than that to the IC, thus resulting in about 300-fold higher affinity of 3F7 for the IC than for MC MAb alone (1.8 x 10(9) M(-1) and 4.6 x 10(6) M(-1) for the IC and MC MAb, respectively). Finally, 3F7 IC MAb was shown to react with the IC formed by the addition of MCLR to MC MAb-coated plates in a dose-dependent manner. Therefore, a new type sandwich immunoassay, anti-immune complex ELISA (IC ELISA) for MCs, was indeed established. The detection limit of the IC ELISA was 2 pg of MCLR ml(-1) (50 fg per assay), making it the most sensitive of all the methods for detecting MCs reported to date.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"83 1","pages":"49-55"},"PeriodicalIF":0.0,"publicationDate":"1999-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73906972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 30

Biosynthetic and genetic relationships of B-series fumonisins produced by Gibberella fujikuroi mating population A. 藤黑赤霉素交配种群A产生b系列伏马菌素的生物合成及遗传关系。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(199911/12)7:6<251::aid-nt64>3.0.co;2-l

R H Proctor, A E Desjardins, R D Plattner

{"title":"Biosynthetic and genetic relationships of B-series fumonisins produced by Gibberella fujikuroi mating population A.","authors":"R H Proctor, A E Desjardins, R D Plattner","doi":"10.1002/1522-7189(199911/12)7:6<251::aid-nt64>3.0.co;2-l","DOIUrl":"https://doi.org/10.1002/1522-7189(199911/12)7:6<251::aid-nt64>3.0.co;2-l","url":null,"abstract":"Fumonisins are mycotoxins produced by the maize pathogen Gibberella fujikuroi mating population A and frequently contaminate maize. Wild-type G. fujikuroi produces four B-series fumonisins, FB1, FB2, FR3 and FB4. These toxins are identical in structure except for the number and positions of hydroxyls along their linear carbon backbone. To elucidate the genetic and biosynthetic relationships among these fumonisins, we conducted meiotic and biochemical analyses of G. fujikuroi mutants with altered fumonisin production that resulted from defective alleles at three loci, Fum1, Fum2 and Fum3. These mutants produced either no fumonisins, only FR2 and FB4, or only FR3 and FR4. Genetic analyses revealed the orientation of the Fum loci along linkage group 1 of the fungus. The mutants were grown together in pair-wise combinations to determine if their fumonisin production phenotypes could be complemented. When FR3- and FB2-producing mutants were grown together, complementation occurred. However, when a nonproducing mutant was grown with a FR2- or FB3-producing mutant, complementation did not occur or was incomplete. When purified FR2, FR3, or FB4 was fed to mutant cultures, FR4 was converted primarily to FR2, FR3 was converted to FB1 and FB2 was not converted. The results from these assays suggest a previously unrecognized branch in the fumonisin biosynthetic pathway.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 6","pages":"251-8"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1522-7189(199911/12)7:6<251::aid-nt64>3.0.co;2-l","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21944407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 23

A yeast bioassay for trichothecenes. 酵母中毛霉烯的生物测定。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(199911/12)7:6<401::aid-nt77>3.0.co;2-a

J Binder

{"title":"A yeast bioassay for trichothecenes.","authors":"J Binder","doi":"10.1002/1522-7189(199911/12)7:6<401::aid-nt77>3.0.co;2-a","DOIUrl":"https://doi.org/10.1002/1522-7189(199911/12)7:6<401::aid-nt77>3.0.co;2-a","url":null,"abstract":"Like all eucaryotic cells, yeasts are sensitive to trichothecenes, especially T-2 toxin and verrucarin A. Based on this sensitivity, a yeast bioassay was developed to evaluate the toxicity of corn samples. The bioassay was optimized using spiked maize extracts. The toxicity of samples was defined as toxicity equivalent to a certain concentration of T-2 toxin standards. The assay can be performed on crude extracts, but the results are more precise after column clean-up. The test can also be used for the screening of trichothecene toxicity in general. The relative standard deviation (RSD) at 85 % growth inhibition (EC85) was 4.5% for the T-2 toxin standards (n = 8). This corresponds to an initial T-2 toxin concentration of approximately 58 ppb in the corn sample. Samples containing 188 and 113 ppb T-2 toxin caused a growth inhibition higher than 85%, whereas samples with toxin concentrations of 56 and 19 ppb had a growth inhibition less than 85%. Therefore the test can be used for the qualitative evaluation of corn samples up to a level of 58 ppb +/- 2.8 ppb. The bioassay is easy to perform with minimum requirements for equipment. Results can be obtained within 24 h and a large number of samples can be analysed daily. The costs are low and the results obtained are repeatable. With some modifications this test can be used for toxicity studies on trichothecene metabolites as well as for extracts with unknown compounds with properties similar to trichothecenes.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 6","pages":"401-6"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1522-7189(199911/12)7:6<401::aid-nt77>3.0.co;2-a","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21945391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Detection of diarrhetic shellfish poisoning toxins from tropical shellfish using liquid chromatography-selected reaction monitoring mass spectrometry. 液相色谱选择反应监测质谱法检测热带贝类中腹泻性贝类中毒毒素。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(199911/12)7:6<361::aid-nt79>3.0.co;2-1

M J Holmes, S L Teo, H W Khoo

引用次数: 8

Fiber-optic immunosensor for mycotoxins. 真菌毒素纤维免疫传感器。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/1522-7189(199911/12)7:6<371::aid-nt86>3.0.co;2-8

C M Maragos, V S Thompson

{"title":"Fiber-optic immunosensor for mycotoxins.","authors":"C M Maragos, V S Thompson","doi":"10.1002/1522-7189(199911/12)7:6<371::aid-nt86>3.0.co;2-8","DOIUrl":"https://doi.org/10.1002/1522-7189(199911/12)7:6<371::aid-nt86>3.0.co;2-8","url":null,"abstract":"Evanescent wave-based fiber-optic immunosensors were studied for the detection of fumonisins and aflatoxins in maize. Two formats, competitive and non-competitive, were used. A competitive format was used to measure fumonisin B1 (FB1) in both spiked and naturally contaminated maize samples. Fumonisin monoclonal antibodies were covalently coupled to an optical fiber and the competition between FB1 and FB1 labeled with fluorescein (FB1-FITC) for the limited number of binding sites on the fiber was assessed. The signal generated in the assay was inversely proportional to the FB1 concentration. For samples, the concentration causing an inhibition of binding by 50% (IC50) was dependent upon the clean-up procedure used. Simple dilution of methanolic maize extracts yielded an assay with an IC50 equivalent to 25 microg FB1 g(-1) maize with a limit of detection of 3.2 microg g(-1) maize. Affinity column clean-up yielded an assay with an IC50 equivalent to 5 microg FB1 g(-1) maize (limit of detection 0.4 microg FB1 g(-1)). An HPLC method and the immunosensor method agreed well for naturally contaminated maize samples except when large amounts of other fumonisins that cross-react with the immunosensor were present. The second sensor format, for the mycotoxin aflatoxin B1 (AFB1), was a non-competitive assay using the native fluorescence of this mycotoxin. Because the fluorescence of AFB1 itself was detected, the response of the sensor was directly proportional to the toxin concentration. The sensor, while capable of detecting as little as 2 ng ml(-1) of AFB1 in solution was technically not an immunosensor, since the attachment of aflatoxin specific antibodies was not required. Sensors of the formats described have the potential to rapidly screen individual maize samples but require coupling with a clean-up technique to be truly effective.","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 6","pages":"371-6"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1522-7189(199911/12)7:6<371::aid-nt86>3.0.co;2-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21946559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 64

Oxidative deamination of hydrolyzed fumonisin B(1) (AP(1)) by cultures of Exophiala spinifera. 尖孢外孢子虫培养对水解伏马菌素B(1) (AP(1))的氧化脱胺作用。

Natural toxins Pub Date : 1999-01-01 DOI: 10.1002/(sici)1522-7189(199902)7:1<31::aid-nt36>3.0.co;2-w

B A Blackwell, J T Gilliam, M E Savard, J David Miller, J P Duvick

{"title":"Oxidative deamination of hydrolyzed fumonisin B(1) (AP(1)) by cultures of Exophiala spinifera.","authors":"B A Blackwell, J T Gilliam, M E Savard, J David Miller, J P Duvick","doi":"10.1002/(sici)1522-7189(199902)7:1<31::aid-nt36>3.0.co;2-w","DOIUrl":"https://doi.org/10.1002/(sici)1522-7189(199902)7:1<31::aid-nt36>3.0.co;2-w","url":null,"abstract":"Fumonisins are mycotoxins of world-wide distribution in maize infected by the fungus Fusarium verticillioides. They are highly toxic to certain livestock and are potential carcinogens. Exophiala spinifera, a black yeast fungus found on moldy maize kernels, was identified previously as capable of growing on fumonisin B1 as a sole carbon source and thus is a potential source for fumonisin detoxifying enzymes. Pure cultures of E. spinifera transform fumonisin B(1) to the amino polyol AP(1) plus free tricarballylic acid through the activity of a soluble extracellular esterase, and further transformation is evidenced by accumulation in culture supernatant of a less polar compound(s) lacking a fluorescamine-reactive amino group. A free amine is thought to be critical for biological activity of FB(1) or AP(1). As a first step towards characterizing this amine-modifying activity, we investigated the biotransformation of AP(1) by E. spinifera liquid cultures that had been previously grown in liquid medium containing AP(1) as a sole carbon source. Accumulation of AP(1)-derived metabolites was monitored by thin-layer chromatography of culture supernatants, and product metabolites were purified and evaluated by mass spectrometry and nuclear magnetic resonance. Two products of treatment of purified AP(1) with cultures of E. spinifera are shown to be N-acetyl AP(1) and a new compound, 2-oxo-12,16-dimethyl-3,5,10, 14,15-icosanepentol hemiketal (or 2-OP(1) hemiketal).","PeriodicalId":18777,"journal":{"name":"Natural toxins","volume":"7 1","pages":"31-8"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/(sici)1522-7189(199902)7:1<31::aid-nt36>3.0.co;2-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21306869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 75