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101.
Mayer F Takeoka GR Buttery RG Whitehand LC Naim M Rabinowitch HD 《Journal of agricultural and food chemistry》2008,56(10):3749-3757
Three tasty (BR-139, FA-624, and FA-612) and two less tasty (R-144 and R-175) fresh greenhouse tomato cultivars, which significantly differ in their flavor profiles, were screened for potent odorants using aroma extract dilution analysis (AEDA). On the basis of AEDA results, 19 volatiles were selected for quantification in those 5 cultivars using gas chromatography-mass spectrometry (GC-MS). Compounds such as 1-penten-3-one, ( E, E)- and ( E, Z)-2,4-decadienal, and 4-hydroxy-2,5-dimethyl-3(2 H)-furanone (Furaneol) had higher odor units in the more preferred cultivars, whereas methional, phenylacetaldehyde, 2-phenylethanol, or 2-isobutylthiazole had higher odor units in the less preferred cultivars. Simulation of the odor of the selected tomato cultivars by preparation of aroma models and comparison with the corresponding real samples confirmed that all important fresh tomato odorants were identified, that their concentrations were determined correctly in all five cultivars, and that differences in concentration, especially of the compounds mentioned above, make it possible to distinguish between them and are responsible for the differential preference. To help elucidate formation pathways of key odorants, labeled precursors were added to tomatoes. Biogenesis of cis- and trans-4,5-epoxy-( E)-2-decenals from linoleic acid and methional from methionine was confirmed. 相似文献
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103.
Alter T Gaull F Kasimir S Gürtler M Fehlhaber K 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(5-6):214-219
The aim of this study was to evaluate the impact of the slaughter process on the Campylobacter (C.) coli prevalence on pig carcasses and finally pork. To detect C. spp., faecal samples, organ samples and surfaces of slaughter pigs were sampled. Additionally, various abattoir surfaces (n=208) and 227 pork and minced meat samples were included in our study.Whereas a high C. spp. prevalence (64.0%) was detectable in the faeces of slaughter pigs (all isolates were identified as C. coli), low detection rates were observed on pig carcasses after the slaughter process before the chilling period (21.1%).The impact of chilling reduced the detection rate of C spp. on pig carcasses even further to 0.8%. Only C. jejuni strains were isolated after the chilling process. Chilling and the associated drying of the skin are responsible for that massive reduction of C. spp prevalence. Significantly more C. spp. were isolated from livers compared to the corresponding carcasses. Only 5 out of 208 swab samples from different surfaces of the abattoir were C. coli positive. Bacteriological investigation could not detect any C. spp. strains from pork and minced pork meat.The low detection rates at the end of the slaughter and processing line indicate that pork may only play a minor role in the transmission of C. coli infections to humans. By genotyping C. coli-isolates from selected animals we were able to demonstrate three possible ways of contamination of the slaughter carcass surface. Genetically highly related strains were detectable on carcass surfaces of consecutively slaughtered animals. Faecal isolates and isolates from the carcass surface showed occasional high similarities. C. coli-genotypes from tonsils and genotypes from the corresponding slaughter carcasses formed a close cluster. 相似文献
104.
Florian KLETTY Mathilde TISSIER Charlotte KOURKGY Fabrice CAPBER Alexandre ZAHARIEV Nicolas CHATELAIN Julien COURTECUISSE Yvon LE MAHO Caroline HABOLD 《Integrative zoology》2019,14(1):65-74
Agriculture intensification, marked by the generalization of crop monoculture, by the increase in plot size and by the reduction of plant diversity, has led to huge decline in wildlife in European farmlands. In such habitat, research has long been biased towards birds and invertebrates, while very few studies have investigated the effect on small mammals. Considering the European hamster, Cricetus cricetus, we therefore review the different techniques that can be used to investigate the impact of environmental changes and conservation measures in small and endangered wild mammals. We suggest that only a multidisciplinary approach will allow exploration of these effects, combining experimental laboratory work on captive‐bred animals with the monitoring of wild individuals. In particular, individual energy balance has to be investigated and measured as accurately as possible, through either biochemical or bio‐logging techniques. It is, indeed, the most affected physiological trait in a changing environment, as it determines both the reproductive output and the survival of the individual. We also discuss the inconvenience of capture–release approaches for such an endangered species and emphasize the disturbance that experimental protocols could impose on the hamster. 相似文献
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106.
Florian Karl Zeugswetter Theresa Polsterer Herbert Krempl Ilse Schwendenwein 《Journal of animal physiology and animal nutrition》2019,103(1):324-330
Objective of this study was to demonstrate the ubiquitous presence of glucose in urine of euglycemic cats by a highly sensitive glucose assay. The local electronic database was searched for results of quantitative urine glucose measurements in cats. A total of 325 feline urine glucose measurements were identified, of which 303 (93%) had been submitted by one of the co‐authors working in a near‐by small animal practice. After the exclusion of patients with kidney disease (n = 60), hyperthyroidism (n = 15), diabetes mellitus (n = 11), multiple diseases (n = 9) or steroid treatment (n = 3), as well as serial measurements (n = 87) and outliers (n = 8), the final study population consisted of 132 cats. Urine creatinine concentration was unavailable in five patients. Whereas all but one cat had glucose concentrations above the detection limit of the assay (0.11 mmol/L, Gluco‐quant Enzyme Kit/Roche Diagnostics), no positive glucose dipstick test result (Combur 9‐Test, Roche Diagnostics) was observed. The median (range) of urinary glucose concentration and the glucose‐to‐creatinine ratio (UGCR) was 0.389 (<0.11–1.665) mmol/L and 0.0258 (0.007–0.517) respectively. The UGCR was not affected by age, gender, breed or leukocyturia, whereas cats with hematuria had slightly higher values. Data show that so‐called “basal glucosuria” is present in the majority of cats and by no means diagnostic for diabetes mellitus or renal glucosuria. This has to be considered when using bio‐analytical methods with a low limit of quantification. 相似文献
107.
Struvite (MgNH4PO4.6H2O) and nitrification inhibitors are applied to soils to, respectively, provide nutrients and reduce nitrogen (N) loss. Given its low N composition (5.7%) relative to that of phosphorus (P, 12.6%) and magnesium (Mg, 9.9%), struvite could be added to soil concurrently with N fertilizers as a source of P and Mg. Nutrient release from struvite could be impacted if nitrification of its ammonium component is reduced by a nitrification inhibitor. Accordingly, a pot trial gauged whether struvite‐fertilized ryegrass had comparable Mg or P uptake and shoot yields with treatments receiving conventional Mg and P fertilizers. Struvite precipitated from milk industry wastewater, or conventional fertilizers, were added to a soil–sand mixture of low fertility. The inhibitor dicyandiamide (DCD) was added to assess its effect on P uptake by ryegrass. Relative to Epsom salt, struvite led to increased Mg uptake without significantly affecting shoot biomass, indicating luxury consumption. Regarding shoot yield and P uptake, struvite was as effective as triple super phosphate. DCD significantly reduced P uptake in the first harvest; the inhibited nitrification of the ammonium is surmised to have diminished struvite dissolution. In later harvests, DCD led to a trend (albeit not statistically significant) of increased biomass; this N‐rich (66% N) compound was probably biodegraded and utilized as an N source. The impact of DCD on P uptake in this experiment was short‐lived. Nevertheless, DCD degradation occurs less rapidly in field conditions, potentially affecting early P supply which is vital for optimum yield. 相似文献
108.
Millet A Lamy E Jonas D Stintzing F Mersch-Sundermann V Merfort I 《Journal of agricultural and food chemistry》2012,60(9):2148-2156
In this study, we compared the analytical fingerprint and bioactivity of three onion extracts, including an aqueous, a methanol, and a fermented aqueous extract. The extracts were characterized by HPLC-DAD, LC-MS, and GC-MS analyses. The antibacterial, antigenotoxic, and antiproliferative activity of these extracts was assessed by means of agar disk diffusion, bacterial growth kinetics, a comet assay, cell cycle distribution analysis, and cell viability testing. Both the aqueous and methanolic extracts showed a typical flavonol-fingerprint as assessed by HPLC measurements and showed little to no bioactivity. The fermented aqueous extract, which lacks the usual onion flavonoid profile, was found to be the most active in all of the assays. This finding indicates that metabolites of onion compounds, generated by lactic acid fermentation, may be more active than their precursor substances. 相似文献
109.
110.