Effects of processing and of storage on the stability of pantothenic acid in sea buckthorn products (Hippophaë rhamnoides L. ssp. rhamnoides) assessed by stable isotope dilution assay

A stable isotope dilution assay for quantification of pantothenic acid in sea buckthorn berries, juice, and concentrate using a four-fold labeled isotopologue of vitamin B5 as the internal standard was adopted using reversed phase liquid chromatography-mass spectrometry with electrospray ionization. Because of a rapid sample clean up procedure without the necessity of external calibration, this methodology permits the accurate analysis of a high number of samples within a short time. Sea buckthorn juice was stored at 25 and 40 degrees C for up to 7 days to determine the effects of storage temperature on the stability of pantothenic acid. Analysis of kinetic data suggested that the degradation follows a first-order model. The results of the experiments showed that storage of sea buckthorn juice for 7 days at ambient temperature (25 degrees C) already resulted in a significant degradation of pantothenic acid of about 18%. The processing effects of juice production and subsequent concentration revealed a decrease of about 6-7% in the juice and of 23% in the juice concentrate.     

Ein Vergleich deutscher und schweizerischer Regensimulatoren nach Regenstruktur und kinetischer Energie

Comparison of German and Swiss Rainfall Simulators - Rain Structure and Kinetic Energy The drop size distributions of the investigated rain are significantly different. The rainfall simulators Swanson, Bonn, Basel and Trier culminate in the 2 - 3 mm drop diameter class (～40%) and thus simulate best the drop size distribution of natural heavy rainfall. The structure and the kinetic energy of the rains of eight rainfall simulators have been investigated. The data are compared to those registered during a thunder-shower at the research station of Mertesdorf near Trier/FRG. The results are summarized as follows:

• The impact velocity of artificial raindrops depends on the water pressure within the rainfall simulator, the initial velocity of the raindrops and the fall height. A correction factor to match the kinetic energy of natural rainfall, which is based on the percentage of deviation from the terminal velocity, can be applied only to some extend.
• With respect to various fall velocities of the artificial raindrops all tested rainfall simulators except one yield a rainfall energy between 19 and 27 J/m² per mm of rainfall.
• The actual amount of precipitation measured at the end of the rainfall experiments sometimes differs significantly from the aimed value of 60 mm/h. Due to this variation, the total rainfall energy during the experiments accumulated to 9 - 15 MJ/ha.
• This high variability depends on the used rainfall simulator. But it also demonstrates the importance of precipitation measurements on the plot during simulations in order to exactly calculate the rainfall energy.

     

Comparative use of faecal egg count reduction test,egg hatch assay and beta-tubulin codon 200 genotyping in small strongyles (cyathostominae) before and after benzimidazole treatment

A survey on benzimidazole (BZ) resistance in small strongyles was performed on three farms in the tenth region in Chile. Samples from a total of 100 horses were tested using the faecal egg count reduction test (FECRT), the egg hatch assay (EHA) and an allele-specific PCR for the detection of beta-tubulin isotype 1 genes coding for phenylalanine (phe) or tyrosine (tyr) at codon 200. In the past, BZ-type drugs have been used within anthelmintic campaigns on all the three farms. This has predictably led to a high degree of BZ resistance at the Valdivia and Ri?ihue farms and to a lesser degree at the Frutillar farm, as demonstrated by all the three tests. The FECRT indicated resistance in every farm by faecal egg count reductions (FECR) of 27% (S.D. +/- 33), 26.5% (S.D. +/- 26.9) and 83.9% (S.D. +/- 22.8) for the Valdivia, Ri?ihue and Frutillar farms, respectively. With the EHA, the following mean LD(50) values were found before and after treatment with fenbendazole (FBZ): 0.093, 0.141 and 0.066 microg TBZ/ml and 0.149, 0.158 and 0.091 microg TBZ/ml, respectively, for the Valdivia, Ri?ihue and Frutillar samples. The corresponding LD(96) values were 0.222, 0.263 and 0.188 microg TBZ/ml before treatment and 0.316, 0.322 and 0.221 microg TBZ/ml after treatment, indicating BZ resistance in all the cases. Genotyping was performed on more than 1700 single larvae, at least 10 per faecal sample, for 98 pre- and 66 post-treatment samples. Despite a general trend toward higher percentages of phe/tyr and tyr/tyr individuals following treatment, no statistically significant difference was found between these two and the phe/phe genotype percentages. However, a significantly negative correlation was detected between the LD(50) values and the phe/phe percentages and there was a positive correlation between the FECRT results and the phe/phe percentages. Thus, there seems to be a difference in the significance of the codon 200 polymorphism in the mechanisms of BZ resistance in small strongyles of the horse and sheep trichostrongyles.     

Pedo-hydrological and sediment responses to simulated rainfall on soils of the Konya uplands (Turkey)

Microplot experiments using a portable rainfall simulator were carried out in April 1992 on 15 Turkish soils with textures ranging from clay loam to loamy clay and slopes from 3° to 12°. In order to determine the effects of a change in land use on infiltration and erosion, pairs of sites with soils developed on identical parent material were chosen. Several physical and chemical properties of the soil were determined and related by regression analysis to various soil loss and infiltration variables.The regression equations showed that plant cover, and therefore the type of land use, was the most important factor. Plant cover influenced various important soil characteristics which determine the infiltration behaviour of the soil, namely humus, root content and macropore distribution. The slope, physical, textural, and chemical properties of the soils and aggregate stability were only of secondary importance. The shear vane test was not well-suited for measuring the surface properties of these soils, which were initially cohesionless and consisted of loose aggregates.Erosion damage mapping showed high rill erosion rates after snow melting and spring rainfalls on tilled and seedbed sites, up and down hill culture, slopes with gradients > 8 degrees, and on northwest exposed slopes. Results of the microplot tests and erosion damage mapping were in general qualitative agreement. On the catchment scale, the variations of the mesoclimate due to exposure and altitude became important.     

Rapid determination of the attenuation limit of beer using middle-infrared (MIR) spectroscopy and a multivariate model

A new approach for the determination of the attenuation limit of beer samples using the specific fingerprint region of middle-infrared (MIR) spectroscopy in combination with multiple regression by partial least-squares (PLS) was developed using an attenuated total reflectance (ATR) module. A specific spectral region between 1200 and 800 cm(-1) was identified as highly informative for the quantification of the limit of attenuation. The absorptions in this region are induced by vibrational bands of ethanol (1080, 1040, and 880 cm(-1)) and dissolved extract, in majority maltotriose (1160-1140 and 1040-980 cm(-1)). The multivariate calibration results in a root mean squared error of calibration (RMSEC) of 0.40% and a validation procedure with independent samples results in a root mean squared error of validation (RMSEV) of 0.50%. A repeatability test, concerning the precision of the developed MIR method as well as the reference method, was analyzed using Student's t test. The test has shown no significant difference between the two random samples.     

The relationship of mucosal bacteria to duodenal histopathology, cytokine mRNA, and clinical disease activity in cats with inflammatory bowel disease

Feline inflammatory bowel disease (IBD) is the term applied to a group of poorly understood enteropathies that are considered a consequence of uncontrolled intestinal inflammation in response to a combination of elusive environmental, enteric microbial, and immunoregulatory factors in genetically susceptible cats. The present study sought to examine the relationship of mucosal bacteria to intestinal inflammation and clinical disease activity in cats with inflammatory bowel disease. Duodenal biopsies were collected from 27 cats: 17 undergoing diagnostic investigation of signs of gastrointestinal disease, and 10 healthy controls. Subjective duodenal histopathology ranged from normal (10), through mild (6), moderate (8), and severe (3) IBD. The number and spatial distribution of mucosal bacteria was determined by fluorescence in situ hybridization with probes to 16S rDNA. Mucosal inflammation was evaluated by objective histopathology and cytokine profiles of duodenal biopsies. The number of mucosa-associated Enterobacteriaceae was higher in cats with signs of gastrointestinal disease than healthy cats (P<0.001). Total numbers of mucosal bacteria were strongly associated with changes in mucosal architecture (P<0.001) and the density of cellular infiltrates, particularly macrophages (P<0.002) and CD3(+)lymphocytes (P<0.05). The number of Enterobacteriaceae, E. coli, and Clostridium spp. correlated with abnormalities in mucosal architecture (principally atrophy and fusion), upregulation of cytokine mRNA (particularly IL-1, -8 and -12), and the number of clinical signs exhibited by the affected cats. These data establish that the density and composition of the mucosal flora is related to the presence and severity of intestinal inflammation in cats and suggest that mucosal bacteria are involved in the etiopathogenesis of feline IBD.     

Effects of open-pond density and caged biomass of Nile Tilapia (Oreochromis niloticus L.) on growth, feed utilization, economic returns and water quality in fertilized ponds

The effects of open‐water and caged fish density on growth, feed utilization, water quality and profitability were investigated to assess the feasibility of a small‐scale rotational system for production of Oreochromis niloticus (L.) in fertilized ponds. Hand‐sexed male fingerlings averaging 18.6 and 29.9 g were stocked in open water and cages, respectively in four treatments with open‐pond:caged tilapia ratios of 300:0 (control), 150:150 (L), 300:150 (H1) and 300:300 (H2). The ponds in L and H1 contained one cage, two cages in H2, and the control ponds had no cages. Each cage contained 150 fish, which were fed daily at 1.5% body weight for 125 days. All fish in the open water except the control fish were not fed. Growth of open water tilapia was significantly (P<0.05) higher in L than in control. Feed utilization, dawn DO and economic returns were significantly better (P<0.05) in caged than control ponds. Growth of tilapia in L was significantly lower (P<0.05) in cages than in open water. Fingerling production was significantly lower (P<0.05) in L than in other treatments. In conclusion, cage‐cum‐open‐pond integrated treatment (L) was optimal for O. niloticus production in fertilized ponds. However, the system could not rotate and needed further fine‐tuning to rotate.     

Population decline in the epiphytic orchid Aspasia principissa

The population dynamics of the epiphytic orchid Aspasia principissa, growing in the moist tropical forest of Barro Colorado Island, Panama, were studied from 1997 until 2004. Using growth analysis, projection matrix analysis, elasticity analysis, and different types of simulations, we identified the components of the life cycle with the strongest effect on population growth rate (λ), and related differences in vital rates to environmental variation, mainly in precipitation. Such information, which is almost completely lacking for tropical orchids, is essential for the efficient conservation of these frequently rare and endangered plants. Elasticity analysis indicated that the population growth rate (λ), which averaged 0.92, was primarily affected by survival, and much less affected by growth or by sexual reproduction. Simulations, which included different levels of pollinator limitation, showed that complete pollination would raise λ to such an extent as to allow long-term persistence of the population. Pollinator limitation per se, however, is presumably not responsible for the currently observed population decline. Instead, we discuss a possible link between low λ and (a) a long-term decline in precipitation and (b) recent increases in forest dynamics: variation in annual rainfall significantly affected both recruitment and growth rates of smaller orchid individuals, while the hypothesised increase in the rates of branch and tree falls would increase mortality rates in this epiphyte.     

Short-term effects of an exceptionally hot and dry summer on decomposition of surface peat in a restored temperate bog

The restoration of drained peat bogs in Northwest (NW) Europe is an important task of soil protection, but needs to cope with warmer and drier summers. Our examination took place in the Pietzmoor bog (Schneverdingen, NW Germany) that had been drained for fuel peat extraction until the 1970s and rewetted since then. We determined carbon dioxide (CO₂) efflux in situ and in laboratory incubations. Also, we analyzed pore water for dissolved organic carbon (DOC), total and dissolved organic N (DON), nitrate (NO₃^–) and ammonium (NH₄⁺) concentration. In Schneverdingen, the summer 2003 was record-breaking hot (mean temperature June to August elevated > 3 K compared to long-term average) and dry (precipitation during the same period < 59% of long-term average). In July 2003, the water table in the Pietzmoor subsided to > 42 cm below the surface in July 2003, when in situ soil CO₂ efflux was up to 23.4 g m^–2 d^–1 compared to 15.7 g m^–2 d^–1 in September. Prior to March 2003, DOC concentrations in pore water were < 180 mg l^–1 and NH₄⁺ was the dominant fraction of mineral N. In July 2003, DOC concentration rose to 249 g l^–1, DON concentrations more than doubled, and NO₃^– became the dominant fraction of mineral N. Due to the increased future likelihood of hot and dry summers in NW Germany, peat bog restoration efforts need take care that a water table close to the surface is maintained.     

Mitteilungen aus der Presse

Mitteilungen

MITTEILUNGEN AUS DER PRESSE