Fusarientoxine (DON und ZEA) in Mehl und Brot

Because of their potential health risk the amount of the Fusariumtoxins deoxynivalenol (DON) and zearalenone (ZEA) is an important quality parameter for cereals.With regard to the fact that in the european union limiting values for these Fusarium-toxins are discussed, the analysis of cerealfood from the market makes sense in order to get a realistic image of the load of consumers. Cereals mainly get in human food chain in form of bread and other bakery products. Publications about evaluation of the influence of the breadmaking process (removal or destruction of mycotoxins by fermentation and heating) are rare and sometimes give contrary results. [3, 4]Our food control laboratory started a monitoring program in order to get more informations about the influence of this bread-making process. Therefore bread and the flours the bread made of are taken from bakeries in district of Tübingen (Germany). First results are presented.     

Karyotypvariation und Heterochromatinmuster bei Igeln (Erinaceus und Hemiechinus)

Zusammenfassung Die Vermutung, daß die Insektivoren in besonderem Maße Strukturvariationen der Chromosomen im Prozeß der Evolution der Arten widerspiegeln, war Ausgangspunkt dieser Arbeit.Die Chromosomenuntersuchungen bei Erinaceus europaeus (Westigel) und E. roumanicus (Ostigel) sowie bei Hemiechinus auritus und H. megalous zeigten, daß alle vier Formen die gleiche Chromosomenzahl von 48 besitzen. H. auritus und H. megalotis haben einen identischen Karyotyp und das gleiche DNS-Replikationsmuster. Der Befund kann als Beleg für die Annahme gelten, daß beide einer gemeinsamen Art zugehören und H. megalotis nur eine Großform von H. auritus darstellt.Beide Arten der europäischen Igel (Erinaceus) besitzen, anders als Hemiechinus, große, spät replizierende und in der Meiose heteropyknotische Segmente, die als autosomales Heterochromatin aufgefaßt werden. Die sehr auffälligen Unterschiede der Karyotypen betreffen überwiegend diese heterochromatischen Segmente des Genoms, die möglicherweise besonders günstige Voraussetzungen für strukturelle Umschichtungen im Laufe der Evolution boten.Vermutlich stellt das autosomale Heterochromatin einen genetisch inaktiven Anteil des Chromosomenkomplements dar. Seine Umlagerung im Laufe der Evolution ließ in cytologischer Hinsicht grobe Variationen des Genoms zu, ohne daß der genetisch aktive euchromatische Bestandteil des Genoms in gleichem Ausmaße betroffen wurde. Die beiden europäischen Igelarten sind dafür ein deutliches Beispiel.

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Karyotype variation and heterochromatin pattern in hedgehogs (Erinaceus and Hemiechinus)

The chromosome variations found in the two European forms of Erinaceus have been studied by the use of ³H-Thymidine autoradiography in karyotype analyses and of meiotic preparations. The observations in Erinaceus are compared with the results of two forms of Hemiechinus. — The Western and the Eastern European hedgehogs (Erinaceus) have 48 chromosomes. Marked karyotypic differences corroborate the view that they represent different species, i.e. E. europaeus and E. roumanicus. Both possess large amounts of late labelling autosomal heterochromatin which corresponds to heteropyknotic non-pairing segments in meiosis and to large chromocenters in the interphase nuclei. — Obviously, the prominent variations of the chromosomes in E. europaeus and E. roumanicus concern the heterochromatic autosomal segments which probably represent genetically inactivated material. It is proposed that the gross karyotypic differences result from translocations, and possibly pericentric inversions, of heterochromatin and, therefore, are of lesser genetic importance. The genetically more effective changes in speciation, however, must mainly be caused by minor rearrangements or gene mutations. — H. auritus and H. megalotis have identical karyotypes (also with 48 chromosomes) and similar DNA-replication patterns. Larger heterochromatic segments are absent from mitotic and meiotic chromosomes. The lack of karyotype differences is in line with biometric data leading to consider H. megalotis as a subspecies of H. auritus. — It is conceivable that heterochromatinization as cytologic mechanism of karyotype evolution is not restricted to the European hedgehogs (Erinaceus). Other mammalian species displaying similar features must, however, be found in order to prove a more general importance of this principle.

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Herrn Prof. Dr. H. Hamperl zum 70. Geburtstag.

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Mit Mitteln des Landesamts für Forschung Nordrhein-Westfalen und der Deutschen Forschungsgemeinschaft.     

Biologie und Verhalten zentralasiatischer Schneefinken (Montifringilla) und Erdsperlinge (Pyrgilauda)

Snow Finches and Mountain-steppe Sparrows differ in habitat selection, feeding, social and vocal behaviour. For these reasons, separation of the genusMontifringilla intoMontifringilla andPyrgilauda is recommended.     

Zygopleuroidea (Gastropoda) aus dem Lias und Dogger Deutschlands und Nordwestpolens

16 taxa of gastropods are described from the Lower and Middle Jurassic of Germany and northwestern Poland. They belong to seven genera. Two species (Pommerozygia aspera, Costazygia bilzi) and two genera (Brevizygia, Costazygia) are new. The family Pommerozygiidae is new as well. Compared to the Zygopleuridae, the Pommerozygiidae have a rather short and broad shell with only few teleoconch whorls. The protoconch is broad conical with a rounded apex (because the first whorls are nearly planispiral). From the Zygopleuridae only members of the Zygopleurinae have been found. Most Jurassic species have a smooth protoconch. Within the Zygopleuridae, the development possibly began with protoconchs carrying collabral axial ribs (and spirals) and led to smooth protoconchs. The genera of the Pommerozygiidae are rather similar to each other. The planktotrophic larval shell has a subsutural row of nodes like many species of Triassic Zygopleuridae. Therefore, both families are closely related. The Pommerozygiidae are possibly a separate branch of the Zygopleuroidea without descendants. The main branch is probably the evolutionary line Zygopleuriidae — Janthinoidea.     

Erbliche Zystennierenerkrankungen: Autosomal-dominante und autosomal-rezessive polyzystische Nierenerkrankung (ADPKD und ARPKD)

medizinische genetik - Zystische Nierenerkrankungen gehören zu den wichtigsten Ursachen eines terminalen Nierenversagens bei Kindern und Erwachsenen. Während die häufigere...     

Deoxynivalenol (DON)- und Zearalenon (ZEA)-Gehalte in Weizen, Roggen und Triticale: Ergebnisse aus der Besonderen Ernteermittlung (BEE) 2001 und 2002

Deoxynivalenol and Zearalenone contents were determined in wheat, rye and triticale samples which were representative of the 2001 and 2002 harvests in Germany. The frequency of DON and ZEA detection and the mean levels of these toxins were higher in wheat, rye and triticale in 2002 in comparison to 2001. The influence of varieties and preceding crop on DON contents in wheat and triticale is presented.

Presented at the 25th Mykotoxin-Workshop in Giessen, Germany, May 19–21, 2003     

Vorkommen und biologische Bedeutung von Benzopyranen (Chromenen) und Benzofuranen in denAsteraceae

Benzopyrans (chromenes) and benzofurans are characteristic natural products of theAsteraceae and are found together with their biogenetic precursors primarily in the tribesAnthemideae, Astereae, Eupatorieae, Heliantheae, Inuleae, andSenecioneae. The accumulation of benzopyrans and benzofurans supports an arrangement of the tribes of theAsteraceae into two groups as suggested recently based on morphological characters. The methods for analysing this class of natural products are demonstrated with the American genusEncelia. Experiments on the localization of benzopyrans and benzofurans inEncelia species indicate that these compounds are stored in resin ducts. Several benzopyrans and benzofurans are biologically active and are repellent as well as toxic towards herbivorous insects. Experiments on structure — activity relationships indicate the biological activities as being influenced by the heterocycle (pyranvs. furan) as well as by the substituents of the aromatic ring. In addition, several tested compounds showed phototoxic activities.

Vorgetragen auf der Tagung der Deutschen Botanischen Gesellschaft, Wien, September 1984.     

ATP-ase und Energieflux-Balance (EB) als kybernetische Regulatoren in Thylakoiden und Mitochondrien

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Die pollenmorphologie der afrikanischen buxus- und notobuxus-arten (buxaceae) und ihre systematische bedeutung

Pollen grains of 8 African species of Buxus and Notobuxus were examined by light and scanning electron microscopy. Three pollen types are recognized based on the exine sculpture and the evolutionary trends of the pollen characters are discussed. Pollen morphology shows the existence of three major systematic groups. These results support the previous classification of an African section Probuxus with two subsections and speak in favor of the generic rank of the Notobuxus species. Together with anatomical and taxonomical data pollen morphology and its evolutionary trends lend support to the suggestions that the centre of origin of the genus Buxus might have been in Africa, while secondary centres of evolution have developed in the neotropical and Eastasian region.