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Mycotoxins Produced by Fungi Isolated from Wine Cork Stoppers  [PDF]
Centeno S.,Calvo M A.
Pakistan Journal of Nutrition , 2002,
Abstract: The research work was conducted to determine the production of mycotoxins from the fungi isolated from wine corks stoppers. When comparing the four fractions of Alternaria alternata obtained by the thin layer chromatography with the standards of tenuazonic acid, alter toxin I, altenuene, alternariol, alternariol monomethyl ether and ten toxin, it can be observed that Alternaria alternata only produces alter toxin I, altenuene and alternariol monomethyl ether. The results showed that the production of citrinin by Penicillium citrinum and of fumonisin B1 by Fusarium moniliforme, due to the fact that the fractions isolated by TLC of these fungi coincide with the controls for such mycotoxins. Fusarium solani did not produce fumosin B1.
Toxicity of Methylated Bismuth Compounds Produced by Intestinal Microorganisms to Bacteroides thetaiotaomicron, a Member of the Physiological Intestinal Microbiota  [PDF]
Beatrix Bialek,Roland A. Diaz-Bone,Dominik Pieper,Markus Hollmann,Reinhard Hensel
Journal of Toxicology , 2011, DOI: 10.1155/2011/608349
Abstract: Methanoarchaea have an outstanding capability to methylate numerous metal(loid)s therefore producing toxic and highly mobile derivatives. Here, we report that the production of methylated bismuth species by the methanoarchaeum Methanobrevibacter smithii, a common member of the human intestine, impairs the growth of members of the beneficial intestinal microbiota at low concentrations. The bacterium Bacteroides thetaiotaomicron, which is of great importance for the welfare of the host due to its versatile digestive abilities and its protective function for the intestine, is highly sensitive against methylated, but not against inorganic, bismuth species. The level of methylated bismuth species produced by the methanoarchaeum M. smithii in a coculture experiment causes a reduction of the maximum cell density of B. thetaiotaomicron. This observation suggests that the production of methylated organometal(loid) species in the human intestine, caused by the activity of methanoarchaea, may affect the health of the host. The impact of the species to reduce the number of the physiological intestinal microbiota brings an additional focus on the potentially harmful role of methanoarchaea in the intestine of a higher organism. 1. Introduction Biomethylation of metals and metal(loid)s is an important process which increases the mobility, bioavailability, and toxicity of these elements. Anaerobic microorganisms, in particular methanoarchaea, show the greatest versatility regarding the spectrum of elements that they methylate [1]. Considering human health, the biotransformation of harmless metals, such as bismuth, by the human intestinal microbiota is a highly relevant process. Due to the low toxicity of metallic bismuth and its inorganic salts, bismuth has been classified as a “green element” [2]. Bismuth is therefore widely used in a variety of applications such as cosmetics, catalysts, industrial pigments, and ceramic additives [3]. Bismuth is, however, associated with several adverse reactions such as encephalopathy, renal failure, and even cases of death in the 70s and 80s [4, 5]. It has been suggested that derivatives of this metal may be responsible for these damages. Our recent studies have shown that, after ingestion of inorganic bismuth, the intestinal microbiota, in particular methanoarchaea, are capable of methylating inorganic bismuth to soluble paritally methylated compounds like monomethyl- (MMBi-) and dimethylbismuth (DMBi) as well as volatile trimethylbismuth (TMBi) [6–10]. TMBi is characterized by a higher volatility and hydrophobicity in comparison
Incidence of Fusarium Species and Mycotoxins in Silage Maize  [PDF]
Sonja Eckard,Felix E. Wettstein,Hans-Rudolf Forrer,Susanne Vogelgsang
Toxins , 2011, DOI: 10.3390/toxins3080949
Abstract: Maize is frequently infected by the Fusarium species producing mycotoxins. Numerous investigations have focused on grain maize, but little is known about the Fusarium species in the entire plant used for silage. Furthermore, mycotoxins persist during the ensiling process and thus endanger feed safety. In the current study, we analyzed 20 Swiss silage maize samples from growers’ fields for the incidence of Fusarium species and mycotoxins. The species spectrum was analyzed morphologically and mycotoxins were measured by LC-MS/MS. A pre-harvest visual disease rating showed few disease symptoms. In contrast, the infection rate of two-thirds of the harvest samples ranged from 25 to 75% and twelve different Fusarium species were isolated. The prevailing species were F. sporotrichioides, F. verticillioides and F. graminearum. No infection specificity for certain plant parts was observed. The trichothecene deoxynivalenol (DON) was found in each sample (ranging from 780 to 2990 μg kg?1). Other toxins detected in descending order were zearalenone, further trichothecenes (nivalenol, HT-2 and T-2 toxin, acetylated DON) and fumonisins. A generalized linear regression model containing the three cropping factors harvest date, pre-precrop and seed treatment was established, to explain DON contamination of silage maize. Based on these findings, we suggest a European-wide survey on silage maize.
Integrable Trilinear PDE's  [PDF]
J. Hietarinta,B. Grammaticos,A. Ramani
Physics , 1994,
Abstract: In a recent publication we proposed an extension of Hirota's bilinear formalism to arbitrary multilinearities. The trilinear (and higher) operators were constructed from the requirement of gauge invariance for the nonlinear equation. Here we concentrate on the trilinear case, and use singularity analysis in order to single out equations that are likely to be integrable. New PDE's are thus obtained, along with others already well-known for their integrability and for which we obtain here the trilinear expression. To appear in the proceedings of NEEDS'94 (11-18 September, Los Alamos)
On Trilinear Oscillatory Integrals  [PDF]
Michael Christ,Diogo Oliveira e Silva
Mathematics , 2011,
Abstract: We examine a certain class of trilinear integral operators which incorporate oscillatory factors e^{iP}, where P is a real-valued polynomial, and prove smallness of such integrals in the presence of rapid oscillations.
Mycotoxins in pathophysiology of cattle diet  [PDF]
Ma?i? Zoran,Adamovi? Milan,?ilas Sandra M.,Mihaljev ?eljko A.
Veterinarski Glasnik , 2003, DOI: 10.2298/vetgl0304191m
Abstract: Depending on the age and production category, cattle show different sensitivity towards certain mycotoxins. Microflora of the rumen degrades to a different degree and inactivates mycotoxins. In the work are presented the most important mycotoxicoses of cattle caused by fungal metabolites from the genera Fusarium, Aspergillus and Penicillium. Poisoning of cattle in our area is most often caused by Zearalenone, Dioxinivalenol, T-2 toxin, Ochratoxin A and Aflatoxin, but in the work are also presented Fumonisin B1 and B2. The work also describes preventive possibilities and protection of animal health from the effects of mycotoxins.
Mycotoxins in poultry production  [PDF]
Resanovi? Radmila M.,Ne?i? Ksenija D.,Nesi? Vladimir D.,Pali? Todor D.
Zbornik Matice Srpske za Prirodne Nauke , 2009, DOI: 10.2298/zmspn0916007r
Abstract: All poultry is sensitive to mycotoxins. This partly depends on the type, age and production categories of poultry, their living conditions and nutritive status and partly on the type, quantity and duration of mycotoxin ingestion. The presence of mycotoxins results in significant health disorders and a decrease in production performances. This leads to considerable economic loss for the poultry industry - either direct losses, i.e. death of the poultry or the indirect ones, i.e. the decrease in body mass, number and quality of eggs, greater food conversion, and immunosuppression. Immunosuppression results in increased sensitivity to infective agents and a bad vaccinal response. Morevover, mycotoxin residues in poultry meat, eggs and products derived from them pose a threat to human health. In order to prevent and reduce the negative implications of mycotoxins in the poultry production, it is necessary to create both global and national strategies for combatting mycotoxins, advance diagnostic techniques and procedures, intensify the control of food quality, introduce new limits on the maximum amount of mycotoxins allowed in food and poultry feed used for certain species and categories of animals, and synchronise it with the European standards.
Mycotoxins and their impact on poultry production  [PDF]
Ivkovi? Goran R.?.,?ivanov Nenad M.,?ivkovi? Jasmina Z.,Milojevi? Milo? J.
Zbornik Matice Srpske za Prirodne Nauke , 2005, DOI: 10.2298/zmspn0508197i
Abstract: Only two years after the great expansion of "AGRO IV" company, it was evident that mycotoxins have great impact on all segments of poultry production. During that year we were for the first time faced up with problems in poultry fattening. It was not possible to explain the present problems only by bacterial and viral infections, so we assumed that there is another reason for the observed clinical picture. From that time we started to pay more attention on contamination of poultry feed with mycotoxins. In the four years' period, from 1988 to 2002, 57 samples were analyzed for the presence of mycotoxins. Mycotoxicological investigations revealed the presence of T-2 toxin in 19 samples at concentrations less than 0.3 mg/kg, in 18 samples at concentration of 0.5 mg/kg, and in 3 samples 1.0 mg/kg. Beside this, type A trichotecene DAS was found in 6 of tested samples, and ochratoxin A and in 1 sample. Clinical picture and damages varied depending on mycotoxins' concentrations and poultry age. To exceede this problem in animal production we tried to use the organic and anorganic mycotoxin adsorbents as additives of poultry feed, but the results were not satisfactory enough. So, we resumed that if we really want to resolve problem of mycotoxins we have to start from the field production of poultry feed components.
Singular lines of trilinear forms  [PDF]
Jan Draisma,Ron Shaw
Mathematics , 2009,
Abstract: We prove that an alternating e-form on a vector space over a quasi-algebraically closed field always has a singular (e-1)-dimensional subspace, provided that the dimension of the space is strictly greater than e. Here an (e-1)-dimensional subspace is called singular if pairing it with the e-form yields zero. By the theorem of Chevalley and Warning our result applies in particular to finite base fields. Our proof is most interesting in the case where e=3 and the space has odd dimension n; then it involves a beautiful equivariant map from alternating trilinear forms to polynomials of degree (n-3)/2. We also give a sharp upper bound on the dimension of subspaces all of whose 2-dimensional subspaces are singular for a non-degenerate trilinear form. In certain binomial dimensions the trilinear forms attaining this upper bound turn out to form a single orbit under the general linear group, and we classify their singular lines.
The Reconstruction of Trilinear Higgs Couplings  [PDF]
A. Djouadi,W. Kilian,M. Muhlleitner,P. M. Zerwas
Physics , 2000,
Abstract: To establish the Higgs mechanism {\it sui generis} experimentally, the Higgs self-interaction potential must be reconstructed. This task requires the measurement of the trilinear and quadrilinear self-couplings, as predicted in the Standard Model or in supersymmetric theories. The couplings can be probed in multiple Higgs production at high-luminosity e+e- linear colliders. We present the theoretical analysis for the production of neutral Higgs-boson pairs in the relevant channels of double Higgs-strahlung and associated multiple Higgs production.
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