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71.
Six novel pyranoanthocyanins were identified by HPLC-ESI-MSn in black carrot (Daucus carota L. ssp. sativus var. atrorubens Alef.) juice. The two major compounds, namely, the vinylcatechol adducts of cyanidin 3-O-(6-O-feruloyl-beta-D-glucopyranosyl)-(1-->6)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside and cyanidin 3-O-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside, respectively, were isolated by a combination of high-speed countercurrent chromatography with semipreparative HPLC. Their structures were fully elucidated by means of one- and two-dimensional NMR spectroscopy and high-resolution mass spectrometry. The four remaining pigments were characterized as the vinylphenol and vinylguaiacol adducts of cyanidin 3-O-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside, the vinylguaiacol adduct of cyanidin 3-O-(6-O-feruloyl-beta-D-glucopyranosyl)-(1-->6)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside, and the vinylcatechol adduct of cyanidin 3-O-(6-O-sinapoyl-beta-d-glucopyranosyl)-(1-->6)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-galactopyranoside. These compounds are formed during storage of the juice through the direct reaction of either caffeic, ferulic, or coumaric acid with the respective genuine anthocyanins. 相似文献
72.
The complete primary structure of the lentil (Lens culinaris) trypsin-chymotrypsin inhibitor LCI-1.7 was determined by conventional methods in order to find relationships between partial sequences and the difference in action against human and bovine chymotrypsin. As other Bowman-Birk type inhibitors, LCI-1.7 contained 68 amino acid residues, seven disulfide bridges, and two reactive sites, Arg16-Ser17 for trypsin and Tyr42-Ser43 for chymotrypsin. Evaluation of sequence homologies showed that it belonged to the group III Bowman-Birk inhibitors. The atypical additional binding site of LCI-1.7 for human chymotrypsin was discussed and compared with such binding sites of two other Bowman-Birk inhibitors, the Bowman-Birk soybean proteinase inhibitor BBI, and the lima bean proteinase inhibitor LBI I, for human and bovine trypsin and chymotrypsin. A concept to reduce the action of these inhibitors against human enzymes by genetic engineering was proposed. 相似文献
73.
Sewenig S Bullinger D Hener U Mosandl A 《Journal of agricultural and food chemistry》2005,53(4):838-844
A new coupling system of GC-GC, connected via a Multi Column Switching Device MCS2 for measuring isotope ratios, is introduced. By means of several standard substances the precise and accurate measurement of isotopic values is proved. First applications concerning the authentication of raspberry aroma compounds are established. Consequently, the combination of constant flow multidimensional gas chromatography-combustion/pyrolysis-isotope ratio mass spectrometry (MDGC-C/P-IRMS) is applied to the authenticity assessment of (E)-alpha(beta)-ionone from six different raspberry cultivars. Furthermore, 12 commercially available raspberry products and samples of (E)-alpha(beta)-ionone, some declared to be natural, are investigated. delta(2)Eta(V)(-)(SMOW) and delta(13)C(V)(-)(PDB) values of (E)-alpha(beta)-ionone are determined, and characteristic authenticity ranges were concluded from raspberries by correlation of both delta(2)Eta(V)(-)(SMOW) and delta(13)C( V)(-)(PDB) values. The results are correlated with the determination of enantiomeric purities of (E)-alpha-ionone, using stir bar sorptive extraction enantio-multidimensional gas chromatography mass spectrometry (SBSE-enantio-MDGC-MS). 相似文献
74.
Krist S Stuebiger G Unterweger H Bandion F Buchbauer G 《Journal of agricultural and food chemistry》2005,53(21):8310-8316
Poppy seed oil (Oleum Papaveris Seminis) is used for culinary and pharmaceutical purposes, as well as for making soaps, paints, and varnishes. Astonishingly, hardly anything was yet known about the volatile compounds of this promising comestible. Likewise, there are no current published data about the triglyceride (TAG) composition of poppy seed oils available. In this investigation solid-phase microextraction (SPME) with DVB/Carboxen/PDMS Stable-Flex fiber was applied to the study of volatile compounds of several seed oil samples from Papaver somniferum L. (Papaveraceae). 1-Pentanol (3.3-4.9%), 1-hexanal (10.9-30.9%), 1-hexanol (5.3-33.7%), 2-pentylfuran (7.2-10.0%), and caproic acid (2.9-11.5%) could be identified as the main volatile compounds in all examined poppy seed oil samples. Furthermore, the TAG composition of these oils was analyzed by MALDI-ReTOF- and ESI-IT-MS/MS. The predominant TAG components were found to be composed of linoleic, oleic, and palmitic acid, comprising approximately 70% of the oils. TAG patterns of the different poppy varieties were found to be very homogeneous, showing also no significant differences in terms of the applied pressing method of the plant seeds. 相似文献
75.
A nuimber of compounds with terpenoid skeletons attached to various functional groups were prepared and tested for their effects as a juvenile hormone in the yellow mealworm Tenebrio molitor. Several of these compounds showed high activity. 相似文献
76.
RATIONALE FOR THIS STUDY: The purpose of this study was to compare the success during the first academic year of students who underwent an admissions procedure (class 2005) and students of the three previous classes (2002-2004), who did not undergo an admissions procedure but took their exams under the same curricular framework. METHODOLOGY: Exam results of 802 students of the 2002-2004 classes were compared with those of 181 students from the 2005 class. RESULTS: Students of the 2005 class were more likely to pass all three exams given in the first academic year than students of the 2002-2004 classes (p < 0.001; OR = 3.2), and the quality of two of the three exams (indicated by individual scores) was also significantly better in 2005 than in the preceding classes (p < 0.001). In unselected classes, 25% to 31% of students showed no successful attempts to pass any of the three exams currently administered. CONCLUSION: The implementation of an admissions procedure measuring, among other indicators, academic ability has significantly improved first-year exam performance. Incoming students presenting with higher scores on academic standards are more likely to complete their courses successfully. 相似文献
77.
Sabine Tappertzhofen 《Journal of pest science》1996,69(7):153-156
Zusammenfassung Populationsveränderungen beiBemisia argentifolii wurden durch Zählungen von Larvenstadien an Blättern und durch Zählung von Adulten, die mit Gelbfallen gefangen wurden, erfaßt. Es wurden drei Typen von Gelbfallen getestet: a) horizontale, etwa 30 cm über dem Boden auf Tischchen ausgebrachte, b) vertikale frei hängende, rechteckige und c) vertikal, frei hängende Zylinder. Die besten Fangergebnisse brachte die Version b), die gleichzeitig den am leichtesten auszubringenden Fallentyp darstellt. Die meisten Nebenfänge wurden mit der horizontalen Falle gemacht.Populationsveränderungen waren abhängig von der Temperatur, Regenfällen, Art und Stärke der Bewässerung, Art, Alter und eventuell Pflanzdichte der Wirtspflanze, Düngung und Insektizidbehandlung. Antagonisten spielten nur eine untergeordnete Rolle.
Bemisia argentifolii war erstaunlich ortstreu. Nach einer ersten Besiedlung wurde die Populationsdynamik sehr kleinräumig fast ausschließlich von der Vermehrungs- und Sterblichkeitsrate bedingt; Wanderungsbewegungen spielten eine untergeordnete Rolle.Durch den Bewässerungsfeldbau wurden klimabedingte Anbaupausen ausgeschaltet. Vergleiche zweier klimatisch ähnlicher Regionen, von denen in einer seit 1991 per Gesetz eine sommerliche Anbaupause für Wirtspflanzen der Weißen Fliege galt, führen zu dem Schluß, daß eine solche Anbaupause trotz Vorkommen von Wildkräutern hilft, den Befall deutlich zu reduzieren. Noch erarbeitet werden muß ein Konzept, wie auch Kleinbauern diese Anbaupausen ohne große finanzielle Verluste überstehen können.
Mit 4 Tabellen 相似文献
Population dynamics ofBemisia argentifolii in the south west of the Dominican Republic
For monitoring whitefly populations, yellow sticky traps were placed in 1993/1994 on 11 sites in two valleys in the south west of the Dominican Republic. Additional countings of immature whiteflyes in untreated parts of field rials were evaluated. Trying different forms of traps showed that flat vertical traps gave better results than flat horizontal or cylindrical ones. The highest catching rates were obtained in eggplant fields as this culture remains long without any pesticide treatment on the field. The dependence of whitefly outbreaks (and yeald losses) on watersupply for the plants could be proofed. The movement in the field seems to be very low. Population dynamics in the field depend mainly on proliferation and nortality. Migration seems to have almost no influence.B. argentifolii was always permanently present on noncultivated lands, but even spots host weeds never reached the population density of cultivated lands. Also parasitoids were always present on noncultivated lands. After the establishment of irrigation, host plants were available and whiteflies could multiply the whole year. Since 1990 planting of host plants is prohibited from March till september in one of the two investigated valleys. This measure seems to be successfull.
Mit 4 Tabellen 相似文献
78.
A proposal of clinical breakpoints for amoxicillin applicable to porcine respiratory tract pathogens
Schwarz S Böttner A Goossens L Goosens L Hafez HM Hartmann K Kaske M Kehrenberg C Kietzmann M Klarmann D Klein G Krabisch P Luhofer G Richter A Schulz B Sigge C Waldmann KH Wallmann J Werckenthin C 《Veterinary microbiology》2008,126(1-3):178-188
In the present position paper, an attempt was made to establish clinical breakpoints of amoxicillin to classify porcine respiratory tract pathogens as susceptible, intermediate or resistant based on their minimum inhibitory concentrations of amoxicillin. For this, a thorough review of the published literature with regard to swine-specific pharmacological data (including dosages of amoxicillin applied and routes of administration used), clinical efficacy, and in vitro susceptibility of the target pathogens was performed. Based on the comparative analysis of the results, the working group "Antibiotic Resistance" of the German Veterinary Medical Society (DVG) proposed to classify porcine respiratory tract pathogens that show MIC values of amoxicillin of < or =0.5microg/ml as "susceptible", those with MICs of 1microg/ml as "intermediate", and those with MICs of > or =2microg/ml as "resistant". 相似文献
79.
Sutor A Schwarz S Conraths FJ 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(11-12):457-464
Some invasive wildlife species have the potential to act as additional host and vector species for parasitic and other infectious diseases. We used the raccoon dog (Nyctereutes procyonides), a carnivore species that has its origin in Asia, as an example to demonstrate biological and ecological prerequisites which enables an invasive species to occupy a new habitat permanently. Studies conducted during the last ten years identified a total of 23 endoparasites, two ectoparasites, six bacterial or protozoan species and five viruses, found in the Nyctereutes procyonoides ussuriensis subspecies in its newly occupied range or in N. procyonoides koreensis in its original range. Results of studies in Finland and Germany furthermore showed that biological characteristics of the raccoon dog make this carnivore an appropriate host or vector for a variety of parasites and infectious diseases. This may result in a growing importance of this invasive carnivore for the epidemiology of transmissible diseases in Germany. Especially with regard to zoonotic disease outbreaks, the raccoon dog should therefore be paid more attention in disease prevention and eradication strategies. 相似文献
80.