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51.
The fungicide fenhexamid [N-(2,3-dichloro-4-hydroxyphenyl)-1-methylcyclohexanecarboxamide] degraded rapidly by UV or sunlight irradiation, yielding 7-chloro-6-hydroxy-2-(1-methylcyclohexyl)-1,3-benzoxazole (CHB) as a main photoproduct. CHB was isolated, and its effect on alcoholic fermentation of Saccharomyces cerevisiae was studied. The results indicate that the presence of CHB does not affect the extent of alcohol production. After 12 days, the amount of CHB in the fermentation medium decreased by ca. 65%. Only 25% of the missing CHB was recovered unchanged from yeasts, most likely because it was adsorbed on the yeast wall cell. The remaining part degraded during the fermentation process. Glucan and chitin, two potential adsorbents, which constitute yeast cell walls, exhibited affinity for CHB.  相似文献   
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Anthocyanins of red orange juices were analyzed by micro-HPLC coupled on-line with an MS detector equipped with an ESI source. The use of microcolumn HPLC greatly enhanced detection performance, allowing direct identification of the anthocyanins present in the orange juices. The use of a soft ionization technique allows detection of the molecular ions of the aglycons. Eight components were identified, five of them for the first time in red orange juice. Three additional anthocyanins were detected, of which only the aglycon was identified.  相似文献   
54.
Resumé La chromatographie en phase gazeuse étant à la fois une méthode qualitative et quantitative, constitue une méthode idéale destinée à résoudre la complexité des analyses des additifs alimentaires. Après une énumération des perfectionnements récents apportés à ces appareils, l'auteur fait un exposé de l'application et des résultats, notamment dans les domaines: Huile d'olive, Beurre, Saindoux, Vin, Cacao, Chocolat. Identification des acides gras, table des constituants, recherches de falsifications, analyse des substances étrangères, altération des vins, discussion des résultats d'analyse.Pour le dosage des résidus de pesticides et pour la recherche des agents antifermentaires, la chromatographie en phase gazeuse s'avère d'une grande utilité en raison de sa précision et sa rapidité.Comme un complément de la chromatographie en phase gazeuse l'auteur insiste sur l'importance, dans le secteur alimentaire, d'une nouvelle méthode d'analyse, basée sur des réactions enzymatiques et sur les études exécutées par son Institut pour la mise ou point de telles méthodes enzymatiques: détermination du glucose, du fructose, du saccharose dans les moûts et les vins, etc...
Summary Gas-chromatography being a qualitative and quantitative method at the same time, makes an ideal method enabling us to solve the complexity of the analyses of food additives. After enumerating the recent improvements in the gas-chromatography equipment the author explains its applications and shows the results obtained, more specially in the following fields: olive oil, butter, lard, wine, cocoa, chocolate, identification of fatty acids, table of components, search for adulterants, analysis of foreign substances, deterioration of wines, discussion of the results of analyses.In the determination of pesticide residues, and the search for antiferments, gas-chromatography appears to be extremely useful, thanks to its precision and rapidity.As a supplement to gas-chromatography the author insists on the importance, in this field of foods, of a new analytical method based on enzymatic reactions, and on the investigations, carried on in this Institute, aimed to set up such enzymatic methods, to be used in the study of glucose, fructose, and saccharose deteriorations in musts and wines, etc...

Zusammenfassung Die Gaschromatographie ist gleichzeitig eine quantitative und qualitative Analysenmethode. Sie ist daher hervorragend für die Lösung der komplexen Probleme auf dem Gebiete der Lebensmittel-Zusatzstoffe geeignet. Nach Aufzählung der letzten Verbesserungen in der Apparatetechnik, werden Anwendungsmöglichkeiten und Ergebnisse besprochen, insbesondere für Analysen von Olivenöl, Butter, Schmalz, Wein, Kakao und Schokolade. Bestimmung der Fettsäuren, Liste der Bestandteile, Nachweis von Fälschungen, Fremdstoffanalysen, Weinalterung, kritische Betrachtung der Ergebnisse.Für den Nachweis der Pestizid-Rückstände und die Bestimmung von Antifermenten, leistet die Gaschromatographie infolge der Genauigkeit und Schnelligkeit der Methode bereits große Dienste.Zur Ergänzung der gaschromatographischen Verfahren schlägt der Autor, insbesondere für Lebensmittelanalysen ein auf enzymatischen Reaktionen fußendes neues Verfahren vor. Hierzu sind die Untersuchungen in seinem Institut weit fortgeschritten, insbesondere für die Bestimmung von Glukose, Fruktose, Saccharose in Most und Wein.
  相似文献   
55.
Thirteen orf virus isolates obtained during the time period between 1995 and 2004 from crusted scab lesions of nine sheep and four goats from different geographical areas of Greece and Italy with suspected contagious ecthyma infection were analyzed. DNA of all isolates was successfully amplified by PCR with the primers 045F-045R and identified them as parapox virus. Partial DNA sequence of orf virus interferon resistant (VIR) gene, phylogenetic analysis of the available isolates and amino acid comparison of the interferon resistance protein encoded by this genomic region was carried out. According to the results of the present report a precise characterisation of the genomic region studied might provide evidence for the genetic variation and movement of the circulating orf virus strains.  相似文献   
56.
An outbreak of giardiasis was observed in a sheep farm in Central Italy. Infected lambs (30-90 days of age) showed a malabsorption syndrome, decreased weight gain and impairment in feed efficiency. The most relevant clinical sign was the excretion of malodorous and poorly formed faeces, whereas diarrhoea was rarely observed in the flock. Laboratory investigations revealed the presence of Giardia in affected animals, while no other significant viral, bacterial or parasitic pathogens were identified in faeces or tissue samples. A mild to severe infiltrative enteritis with eosinophils, lymphocytes and plasma cells was detected in histological sections of the gut. Giardia parasites collected from duodenal aspirates were typed as Giardia duodenalis Assemblage B, by PCR amplification and sequencing of the TPI gene. Treatment with fenbendazole at a dose of 10mg/kg for 3 consecutive days, successfully cleared the infection. These results show that G. duodenalis can cause significant economic losses in sheep farming.  相似文献   
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The species Cynara cardunculus includes the globe artichoke (var. scolymus), the cultivated cardoon (var. altilis) and the wild cardoon (var. sylvestris). The three taxa are sexually compatible and originate fertile F 1 progenies, which, given the high heterozygosity of the species, are highly segregating. We report the characterization of two F 1 populations, one bred from a cross between globe artichoke and cultivated cardoon, and the other between globe artichoke and wild cardoon. Both populations featured a wide array of phenotypes in relation to several traits, and some of the newly developed genotypes are of interest for the ornamental market. The two populations were genotyped at 50 microsatellite (SSR) loci: in the globe artichoke × wild cardoon and globe artichoke × cultivated cardoon progenies 116 and 97 alleles were respectively detected. SSR pattern scores were used to produce an UPGMA dendrogram and a PCoA plot. A set of nine SSR loci, evenly dispersed across the genome, was shown to be sufficient to unambiguously identify each segregant. The molecular fingerprinting is useful for establishing the true to type correspondence of propagative materials in nurseries and ensures the effective correspondence between the real and the declared identity of a clone.  相似文献   
59.
Objective-To determine glycohistochemical characteristics of enzootic nasal tumors (ENTs) of sheep, compare results for ENT with those of histologically normal nasal mucosa of sheep, and identify the histologic origin of ENT. Sample-ENT and nasal mucosa samples obtained from cadavers of 5 adult Lacaune sheep with ENT and 5 Lacaune sheep unaffected by ENT, respectively. Procedures-Samples of ENT and nasal mucosa were collected from cadavers of sheep and sectioned. Conventional and lectin histochemical analyses were used to identify glycoconjugates in tissue sections on the basis of their principal chemical groups and principal terminal or internal oligosaccharidic glucidic residues, respectively. Results-ENTs had papillary and tubular portions. Cells in the papillary portion of ENTs had secretion and surface glycoconjugates, which included sulfated glycosaminoglycans and neutral and sialilated glycoproteins. Cells in the tubular portion of ENTs had surface glycoconjugates, which included neutral and sialilated glycoproteins. Both portions of ENTs had C(4)-acetylated sialoderivatives that were not detected in sections of histologically normal nasal mucosa. Conclusions and Clinical Relevance-The papillary portion of ENTs in sheep may originate from respiratory glands and goblet cells. The tubular portion of ENTs in sheep may originate from olfactory glands. Presence of C(4)-acetylated sialoderivatives in cells of ENTs could confer resistance against pathogens to those cells.  相似文献   
60.
Follicular dendritic cells (FDCs) residing within ileal Peyer's patches (PPs) are of crucial relevance for sheep scrapie early pathogenesis and subsequent scrapie prion neuroinvasion. In this study, ileal PP follicles were significantly more numerous in lambs than in adult Sarda breed sheep, with significant differences being also found in lymphoid follicle area, perimeter and FDC density. Furthermore, PrPd deposition within ileal PPs and host's PrP genotype did not significantly influence these parameters. We conclude that age significantly affects FDC density in ileal PPs from Sarda breed ovines, independently from host's scrapie status and PrP genotype.  相似文献   
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