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31.
32.
B. Huber und H. Mayer 《Journal of pest science》1962,35(10):157
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33.
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34.
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35.
From wine to pepper: rotundone, an obscure sesquiterpene, is a potent spicy aroma compound 总被引:1,自引:0,他引:1
Wood C Siebert TE Parker M Capone DL Elsey GM Pollnitz AP Eggers M Meier M Vössing T Widder S Krammer G Sefton MA Herderich MJ 《Journal of agricultural and food chemistry》2008,56(10):3738-3744
An obscure sesquiterpene, rotundone, has been identified as a hitherto unrecognized important aroma impact compound with a strong spicy, peppercorn aroma. Excellent correlations were observed between the concentration of rotundone and the mean 'black pepper' aroma intensity rated by sensory panels for both grape and wine samples, indicating that rotundone is a major contributor to peppery characters in Shiraz grapes and wine (and to a lesser extent in wine of other varieties). Approximately 80% of a sensory panel were very sensitive to the aroma of rotundone (aroma detection threshold levels of 16 ng/L in red wine and 8 ng/L in water). Above these concentrations, these panelists described the spiked samples as more 'peppery' and 'spicy'. However, approximately 20% of panelists could not detect this compound at the highest concentration tested (4000 ng/L), even in water. Thus, the sensory experiences of two consumers enjoying the same glass of Shiraz wine might be very different. Rotundone was found in much higher amounts in other common herbs and spices, especially black and white peppercorns, where it was present at approximately 10000 times the level found in very 'peppery' wine. Rotundone is the first compound found in black or white peppercorns that has a distinctive peppery aroma. Rotundone has an odor activity value in pepper on the order of 50000-250000 and is, on this criterion, by far the most powerful aroma compound yet found in that most important spice. 相似文献
36.
Tran JL Horvath C Krammer S Höller U Zentek J 《Journal of animal physiology and animal nutrition》2007,91(1-2):40-47
The objective was to investigate in a survey study the blood vitamin concentrations in healthy dogs fed non-specified commercial complete diets and in an intervention study to determine the effects of defined dietary vitamin intakes on blood vitamin levels and hair and skin condition. Sixty-four privately owned dogs, aged from 1 to 8 years, without history of skin or coat problems were included. All animals were fed commercial complete diets with uncertain vitamin concentrations before enrolment. The animals were assigned, according to weight and gender, to four groups with graded vitamin intakes. The blood vitamin levels and skin and coat quality of the dogs were investigated at days 0 and day 122. Coat and hair condition was not influenced by the experimental diets. The retinol concentrations were reduced at the end of the experiment compared with the baseline levels, retinyl esters were not influenced. 25-Hydroxycholecalciferol decreased in all groups, alpha-tocopherol was constant or tended to decrease. Ascorbic acid, thiamine pyrophosphate and riboflavin concentrations were not affected by treatment, flavin adenine dinucleotide and pyridoxal-5'-phosphate were partially reduced on day 122. Cobalamin, pantothenate and biotin concentrations increased with higher dietary intakes, folate levels in tendency. In conclusion, this study gives a survey of blood vitamin concentrations in healthy dogs and provides a data base for the evaluation of the vitamin status in health and disease. 相似文献
37.
St. Scheurer und K. Bauer-Dubau 《Anzeiger für Sch?dlingskunde》1999,72(1):14-18
During 1991 to 1997 4078 samples sent in by public and private institutions were tested for their attack by arthropods. 5994
determinations were done. Seven the store damaging species of Lepidoptera were observed.Plodia interpunctella was the prime pest (305 determinations, mainly in cornflakes, muesli, sunflower seeds, nuts, feed, milk porredge and chocolate
products). The percentage ofP. interpunctella increased from 4,3% (1991) to 5.6%–8.4% (for 1993). Larvae and adults and pure larvae samples ofP. interpunctella were mainly noticed from September to November.
Pure adults samples could be counted for the most part from March to September.
27 the store damaging Coleoptera-species were determined.Stegobium paniceum was the prime pest (164 samples).
4% of the samples involvedS. paniceum. Further mainly observed beetle-species were:Lasioderma serricorne (36 samples),Tenebrio molitor (in 75 samples) andTrogoderma angustum (134 samples).
Aktualisierte Fassung des auf der Jahrestagung des Arbeitskreises Medizinische Arachno-Entomologie der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie (K?ln/ Monheim, 1 und 2. 10. 1997) gehaltenen Vortrages. 相似文献
Aktualisierte Fassung des auf der Jahrestagung des Arbeitskreises Medizinische Arachno-Entomologie der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie (K?ln/ Monheim, 1 und 2. 10. 1997) gehaltenen Vortrages. 相似文献
38.
Inga Mewis und Ch. Ulrichs 《Anzeiger für Sch?dlingskunde》1999,72(5):113-121
The present study examined the morphological and physiological effects of amorphous diatomaceous earth against the stored
product pestsS. granarius, T. molitor andT. confusum. Diatomaceous earth, namely Fossil Shield? and Dryacide? increased the mortality rate of this insects. After contact with Fossil Shield? the individuals ofS. granarius had significant lost of weight and reduced their water content respectively. This showed that silica dusts break the water
barrier of the cuticle. However, it increases the transpiration rate of water across the cuticle and the insect died past
several times through dehydration. As well, an addition of food affected the effectiveness of dusts against insects. A lot
of stored product beetles will be able to produce metabolic water of feed substrates. This ability protects and weaves contrary
to the loss of water. Diatomaceous earth’s can be effective primarily through the sorptive properties of the hygroscopic particles.
One day after dust treatment a significant weight loss ofT. molitor pupae was recorded. The exposure to the silica dust Fossil Shield? caused partly an incomplete metamorphosis and death of the individuals. Pupae dipped in Fossil Shield? or abrasive aluminium dust and rolled for further five minutes, reduced not significant higher their weight as unrolled exuvial
stages. The morphological analyses of treated insects under the Scanning Electron Microscope showed, that the dust covered
the hole integument. Partly, the silica particles sunk into the cuticle. After application of Fossil Shield? at the cuticle of adults,T. molitor, did not show any wax layer. Also it could not be found once blocked by stigma of the mealworm. The dust particles accumulated
around the respiration openings and they partly overgrew.
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39.
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40.
S. Handl U. Wehr J. Zentek S. Krammer‐Lukas 《Journal of animal physiology and animal nutrition》2009,93(1):76-82
Lactoferrin is a natural compound in the milk of mammals and was shown to influence the intestinal micro‐flora and the immune system in mice, calves, dogs and man. The present study was carried out to investigate the effect of orally administered bovine lactoferrin (0, 30, 60 and 120 mg/kg DM feed) on the intestinal morphology and lymphocyte colonization in 36 motherless raised puppies. Endoscopic biopsies from duodenum and colon, taken in week 14, were scored histologically after staining with haematoxylin and eosin (H&E) and lymphocytes (CD3+, CD4+, CD8+) and plasma cells (IgA+, IgG+, IgM+) were enumerated after immunohistochemical staining by computer‐aided quantification. Histological scoring revealed no significant differences amongst the groups. IgG+ plasma cells were reduced (p < 0.05) in the lamina propria of the colon of the 30 and the 60 mg group. The number of CD8+ lymphocytes was higher (p < 0.05) in the epithelium of the colon of the lactoferrin groups. In conclusion, this study indicated only minimal effects of bovine lactoferrin on the population of selected immune cells in the gut mucosa of puppies. More investigations are needed to describe the impact of lactoferrin on the digestive physiology of puppies. 相似文献