[en] Intravenous infusion of endotoxins causes a rapid and pronounced release of prostaglandin F_2α in the mare, cow, goat and sow. In the doe a marked relationship exists between the dose of endotoxin administered and the amount of prostaglandin released. Endotoxin-mediated prostaglandin release can affect luteal function, causing shortening of the oestrous cycle or abortion in pregnant animals. (author)

[en] In aflatoxin radioimmunoassay the following indicators are determined: total radioactivity of the sample, proportion of specific bond, proportion of nonspecific bond, formal detection threshold, specific bond inhibition. The calculation method is given for each indicator. The plotting is designed of calibration dependence of the determination of values of reference samples and accuracy is discussed. The paper is oriented to the fundamentals of processing and the evaluation of results. (M.D.)

[en] Methods for preparation of labelled ochratoxin A and B are described. The method for preparation of labelled ochratoxin B involves the synthesis of the azide of ochratoxin β via the mixed anhydride and subsequent conjugation to labelled phenylalanine to yield ¹⁴C-ochratoxin B. The labelled ochratoxins were injected into male Wistar rats and after different survival times they were sacrificed and subjected to whole body autoradiography. The distribution pattern of ochratoxin A in the rat did not differ from that earlier registered for mouse. The previously known, high susceptibility of rats (and not mice) to ochratoxin A-induced cancer could thus not be explained by an accumulation of the toxin in specific cells or organs. The distribution patterns of ochratoxin A and B were almost congruent - the only apparent difference being a much longer retention of the labelled ochratoxin A in the blood compared to ochratoxin B, which was much faster excreted. When analyzing tissue extract for labelled metabolites only the extracts from the rats injected with ochratoxin B were found to contain easily detectable concentrations, while no metabolites of ochratoxin A were seen. (au)

[en] Abstract only

[en] Cross-reactions and resulting nonspecific binding of substances with structures resembling aflatoxins (derivatives of coumarin, and cinnamonic and benzoic acids, etc.) were investigated. The concentrations of these substances causing erroneously high or false positive values in radioimmunoassay were determined. One μg aflatoxin B₁/kg sample may be simulated by the occurrence of 5 g coumarin, 10 g caffeic acid, 16 g chlorogenic acid, or 15 g vanillin/kg fodder or food sample

[en] Aspergillus flavus was grown on maize and rice extract agars and on irradiated viable cracked maize and rice grains, either in pure culture or in dual culture with wild strains of either Hyphopichia burtonii or Bacillus amyloliquefaciens. Aflatoxin production by A. flavus and its growth and interactions with the other microorganisms were studied at three water activities (a/sub w/) (0.98, 0.95, and 0.90) and two temperatures (25 and 16⁰C). Both H. burtonii and B. amyloliquefaciens markedly stimulated growth and aflotoxin production by A. flavus on cracked maize, especially at 25⁰C and 0.95 and 0.98 a/sub w/. No aflatoxin was detected in pure cultures of A. flavus on cracked rice after 12 days of incubation at 25⁰C, but some was produced by mixed cultures at 16⁰C and 0.98 a/sub w/. The morphological interactions among A. flavus, H. burtonii, and B. amyloliquefaciens were also examined on maize and rice extract agars under similar controlled conditions

[en] This book describes the nature, source, analysis and detection of marine toxins, freshwater toxins and mycotoxins. The first part covers functional and analytical methods to monitor the presence of the toxins in food, and the different technical approaches. There is a full chapter dedicated to the need for certified calibrants and materials for analysis and quantitation, and two chapters to discuss how to evaluate in vitro and in vivo the acute toxicity of natural food toxins. The last chapters describe the nature of each of the known toxin groups, with a final chapter covering the different technical options to analyze the presence of toxins in the environment.

[en] Full text: The kinetics of degradation of natural polycyclic toxins in grains and dried fruits under the influence of UV-light and ionizing radiation ⁶⁰C and the probability of radiolytic detoxication of these products has been studied for the first time

[en] The described method allows to determine picogram amounts of the total of aflatoxins in biological materials. [2,3-can be prepared to a specific activity of min. 30 Ci/mmol and whose use may increase the sensitivity of radioimmunoassay up to 6 pg/0.1 ml of sample. Examples are given of the determination of aflatoxin in milk and in fodder. (M.D.)

No abstract available