Detection of hexabromocyclododecane and its metabolite pentabromocyclododecene in chicken egg and fish from the official food control     

Hiebl J  Vetter W 《Journal of agricultural and food chemistry》2007,55(9):3319-3324

During routine gas chromatography with electron capture detection (GC/ECD) analysis of chicken eggs, we observed that the most prominent peak in some samples did not match the retention time of any of the food contaminants screened. Subsequent GC coupled with mass spectrometry (GC/MS) studies clarified that the mass spectrum of the peak was very similar to hexabromocyclododecane (HBCD), which was also identified by GC/MS in the egg. The unknown compound was positively identified as pentabromocyclododecene (PBCDE), a metabolite of HBCD detected for the first time in foodstuffs. Studies of the analytical method used for the analysis of pesticides and contaminants showed that this cleanup method was suitable for the determination of HBCD and PBCDE, but storage of sample extracts resulted in the loss of HBCD when the sample extracts were not sufficiently purified. The concentrations of HBCD and PBCDE in the high polluted sample were 2.0 and 3.6 mg/kg egg fat. HBCD and PBCDE were also detected in two additional eggs at lower levels (<0.15 mg/kg), whereas 75 eggs did not contain these compounds (<0.02 mg/kg). We also detected HBCD and PBCDE in two samples of whitefish (Coregonus sp.), while an eel sample (Anguilla anguilla) positively tested for HBCD did not contain PBCDE. Surprisingly, the potential metabolite of HBCD, PBCDE, has not been detected before in any food or environmental sample. The present results indicate that more attention should be paid to the detection of HBCD and its metabolite PBCDE in chicken eggs.  相似文献   

Increased dietary protein‐to‐lipid ratio improves survival during naturally occurring pancreas disease in Atlantic salmon,Salmo salar L.     

Jens‐Erik Dessen  Turid Mrkre  Jan Ivar Bildy  Stig N. Johnsen  Lars Thomas Poppe  Bjarne Hatlen  Magny S. Thomassen  Kjell‐Arne Rrvik 《Journal of fish diseases》2019,42(1):21-34

This study demonstrated that increased dietary protein‐to‐lipid ratio (P/L‐ratio) improved survival of farmed Atlantic salmon naturally affected by pancreas disease (PD). In addition to diet, body weight (BW) and delousing mortality prior to the PD outbreak also contributed significantly (p < 0.05) to explain the observed variation in PD‐associated mortality. Subsequent to the PD outbreak, large amount of fish failed to grow and caused thin fish with poor condition (runts). At the end of the trial, significantly (p < 0.05) lower amounts of runt fish and increased amount of superior graded fish where detected among fish fed increased P/L‐ratio and within the fish with the largest BWs prior to PD. Diet, BW and delousing mortality contributed significantly (p < 0.05) to explain the variation in the amount of superior graded fish, whereas BW and diet explained the variation in the amount of runt fish. A significant (p < 0.01) negative linear relationship was observed between the amount of superior graded fish and the total mortality, whereas a positive linear relationship was detected between percentage of fillets with melanin and the total mortality. Thus, increased dietary P/L‐ratio seem to reduce the mortality and impaired slaughter quality associated with PD.  相似文献   

Zur Frage der Erziehung junger Fichtenbest?nde     

Josef Bohdanecky 《Forstwissenschaftliches Centralblatt》1926,48(11):777-783

Ohne Zusammenfassung Nachstehende Abhandlung übersandte mir der Berfasser im August 1917, damit fie verabredetermaszen als Anhang in der 2. Auflage meiner „Freien Durchsorftung“ erscheinen solle, ebenso wie eine Arbeit von Forstmeister Josef Bogl in Salzburg über den „Lichtungsbetrieb“ und ein Aufsatz von Forstmeister D. Moosmaner in Winzingen (Württemberg) über „Durchforstung nach ber Schaftform“. Letzterer kam inzwischen abgesondert in der Silva. Die genannte 2. Auflage erschien nicht, wie ver?ffentlicht, teils infolge des Krieges und seiner Nachwehen, teils wegen sonstiger Schwierigkeiten, u. a. des ju grosz gemordenen Umfangs, wobei das Werk noch nicht ganz fertig war.  相似文献   

Dietary Elements and Quality Parameters of 34 Old and Eight Commercial Apple Cultivars Grown at the same Site in South Tyrol,Italy     

Sara Agnolet  Flavio Ciesa  Evelyn Soini  Anna Cassar  Aldo Matteazzi  Walter Guerra  Peter Robatscher  Alberto Storti  Sanja Baric  Josef Dalla Via  Michael Oberhuber 《Erwerbs-Obstbau》2017,59(3):171-183

Apple is one of the most widely produced and consumed fruits worldwide and hence, complete data of apple composition are important for human diet. Currently, a limited number of cultivars dominate the market, while many others, with a potentially higher nutritional value, are neglected by consumers. The present work reports the content of the dietary elements potassium (K), phosphorus (P), calcium (Ca) and magnesium (Mg) as well as the content of the macroelement nitrogen (N) of 34 old cultivars grown at the same site under identical conditions in South Tyrol, Italy. Their elemental composition was assessed along with quality parameters such as fruit weight, firmness, and soluble solid content and total acidity at harvest and post storage. For selected cultivars the measurements were performed over two or even three different harvest years. Comparison with eight commercial cultivars chosen to represent the fruit currently dominating the market was performed.Besides offering a valuable insight in the variation of dietary elements among old and commercial apple cultivars in up to three harvest years, this study, that complements current nutritional databases, recommends several old cultivars with high content of dietary elements for further study and eventual re-introduction in niche markets.  相似文献   

Distribution of invasive plants in urban environment is strongly spatially structured     

Kateřina Štajerová  Petr Šmilauer  Josef Brůna  Petr Pyšek 《Landscape Ecology》2017,32(3):681-692

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Microbial assimilation of plant-derived carbon in soil traced by isotope analysis   总被引：3，自引：0，他引：3  

Oliver Pelz  Wolf-Rainer Abraham  Matthias Saurer  Rolf Siegwolf  Josef Zeyer 《Biology and Fertility of Soils》2005,41(3):153-162

The flow of new and native plant-derived C in the rhizosphere of an agricultural field during one growing season was tracked, the ratios in different soil C pools were quantified, and the residence times (s) were estimated. For this the natural differences in ¹³C abundances of: (1) C₄ soil (with a history of C₄ plant, Miscanthus sinensis, cultivation), (2) C₃ soil (history of C₃ plant cultivation), and (3) C_4/3 soil (C₄ soil, planted with a C₃ plant, Triticum aestivum) were used. Total amounts and ¹³C values of total soil C, non-hydrolysable C, light fraction C, water-soluble C, microbial biomass C, and phospholipid fatty acids (PLFA) were determined. Using the ¹³C values of soil C in a mixing and a 1-box model enabled the quantification of relative contributions of C₃ plant and C₄ plant C to the total amount of the respective C pools in the C_4/3 soil and their s. Compared to early spring (March), the percentage of C₃ plant C increased in all pools in June and August, showing the addition of new C to the different soil C fractions. In August the contribution of new C to microbial biomass C and water-soluble C reached 64 and 89%, respectively. The s of these pools were 115 and 147 days. The ¹³C values of the dominant soil PLFA, 18:17c, cy19:0, 18:19c, 16:0, and 10Me16:0, showed wide ranges (–35.1 to –13.0) suggesting that the microbial community utilized different pools as C sources during the season. The ¹³C values of PLFA, therefore, enabled the analysis of the metabolically active populations. The majority of ¹³C values of PLFA from the C_4/3 soil were closely related to those of PLFA from the C₃ soil when T. aestivum biomass contributions to the soil were high in June and August. Specific populations reacted differently to changes in environmental conditions and supplies of C sources, which reflect the high functional diversity of soil microorganisms.  相似文献   

Effects of pioneering plants on microbial structures and functions in a glacier forefield   总被引：1，自引：0，他引：1  

Ciro Miniaci  Michael Bunge  Laurence Duc  Ivan Edwards  Helmut Bürgmann  Josef Zeyer 《Biology and Fertility of Soils》2007,44(2):289-297

This study investigates the small-scale spatial impact of the pioneering plant Leucanthemopsis alpina (L.) Heywood (L. alpina) on biological and chemical–physical parameters in an early successional stage of a glacier forefield. Considering the frequent occurrence of isolated patches of this pioneer plant in the forefield of the Dammaglacier (Switzerland), we hypothesized that the impact of the plant would establish gradients in nutrients, and microbial community structure and activity that may be of importance for the successional processes occurring in the forefield. Our results indicated that, in young successional soils, the rhizosphere effect of L. alpina plant patches can influence bacterial cell numbers and activities not only within the root zone, but even at 20 cm distance from the plant. Microbial cell counts, active cells, and saccharase, glucosidase, and acid phosphatase activities revealed significant distance effects, decreasing from soil directly underneath the plant to soils at 20 and 40 cm distance. Soil chemical and physical parameters did not exhibit significant trends. Fingerprinting analysis of amplified 16S rDNA fragments was used to characterize the microbial community. A selective effect of the plant on the microbial community could not be shown because the bacterial communities were similar regardless of distance to the plant.  相似文献