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41.
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Frank O Blumberg S Krümpel G Hofmann T 《Journal of agricultural and food chemistry》2008,56(20):9581-9585
Recent investigations on the bitterness of coffee as well as 5- O-caffeoyl quinic acid roasting mixtures indicated the existence of another, yet unknown, bitter lactone besides the previously identified bitter compounds 5- O-caffeoyl- muco-gamma-quinide, 3- O-caffeoyl-gamma-quinide, 4- O-caffeoyl- muco-gamma-quinide, 5- O-caffeoyl- epi-delta-quinide, and 4- O-caffeoyl-gamma-quinide. In the present study, this orphan bitter lactone was isolated from the reaction products generated by dry heating of 5- O-caffeoylquinic acid model, and its structure was determined as the previously unreported 3- O-caffeoyl- epi-gamma-quinide by means of liquid chromatography-mass spectrometry (LC-MS) and one-/two-dimensional NMR experiments. The occurrence of this bitter lactone, exhibiting a low bitter recognition threshold of 58 micromol/L, in coffee beverages could be confirmed by LC-MS/MS (negative electrospray ionization) operating in the multiple reaction monitoring mode. 相似文献
43.
van het Hof KH Gärtner C Wiersma A Tijburg LB Weststrate JA 《Journal of agricultural and food chemistry》1999,47(4):1582-1586
Palm oil carotenoids are a mixture of alpha- and beta-carotenes, which are used as food colorants. They may also be applied as a functional food ingredient because of the provitamin A activity of alpha- and beta-carotenes and their proposed beneficial roles in the prevention of chronic diseases. This paper discusses the results of an incomplete balanced crossover study with 69 healthy adult volunteers to compare palm oil carotenoids with synthetic beta-carotene in their efficacies to increase plasma levels of carotenoids. Four days of supplementation with natural palm oil carotenoids (7.6 mg/day of alpha-carotene, 11.9 mg/day of all-trans-beta-carotene, 7.5 mg/day of cis-beta-carotene) or synthetic beta-carotene (23.8 mg/day of all-trans-beta-carotene, 4.4 mg/day of cis-beta-carotene), added to a mixed meal, resulted in significant increases in plasma levels of the supplied carotenoids as compared to consumption of a low-carotenoid meal (i.e., 7.2-fold increase in alpha-carotene and 3.5-fold increase in all-trans-beta-carotene following palm oil carotenoids; 6.9-fold increase in all-trans beta-carotene following synthetic beta-carotene). As the carotenoid content differed between the treatments, the relative plasma responses were calculated per milligram of beta-carotene intake. These were similar for the two supplements, suggesting that the presence of alpha-carotene does not affect the bioavailability of beta-carotene from palm oil. It was concluded that 4 days of supplementation with palm oil carotenoids or synthetic beta-carotene improves the plasma beta-carotene status substantially, whereas alpha-carotene is additionally delivered by the palm oil supplement. 相似文献
44.
Prange A Modrow H Hormes J Krämer J Köhler P 《Journal of agricultural and food chemistry》2005,53(17):6930-6938
Cereals contaminated by Aspergillus spp., Penicillium spp., and Fusarium spp. and their mycotoxins, for example, ochratoxin A (OTA) and deoxynivalenol (DON), are not only a risk to human and animal health but can also show poor technological properties and baking quality. The influence of these genera on the sulfur speciation of low molecular weight (LMW) subunits of glutenin was characterized by investigating suboptimally stored wheat samples in situ by X-ray absorption near edge structure (XANES) spectroscopy and baking tests. Field fungi of the genus Fusarium have hardly any influence on both the sulfur speciation of wheat gluten proteins and the baking properties, whereas storage fungi of the genera Aspergillus and Penicillium have a direct influence. An increased amount of sulfur in sulfonic acid state was found, which is not available for thiol/disulfide exchange reactions in the gluten network, and thus leads to a considerably reduced baking volume. From changes of the composition of the mould flora during suboptimal storage of wheat and from the mycotoxin contents, it can be concluded that microbial competitive interactions play an important role in the development of the mould flora and the mycotoxin concentrations during (suboptimal) storage of wheat. 相似文献
45.
Väli Ülo Mirski Paweł Sein Gunnar Abel Urmas Tõnisalu Grete Sellis Urmas 《Landscape Ecology》2020,35(7):1667-1681
Landscape Ecology - Biodiversity is closely related to landscape heterogeneity, but both are difficult to evaluate directly. Apex predators, such as raptors, are potential surrogate indicators of... 相似文献
46.
Role of adenine nucleotide translocator 1 in mtDNA maintenance 总被引:1,自引:0,他引:1
Kaukonen J Juselius JK Tiranti V Kyttälä A Zeviani M Comi GP Keränen S Peltonen L Suomalainen A 《Science (New York, N.Y.)》2000,289(5480):782-785
Autosomal dominant progressive external ophthalmoplegia is a rare human disease that shows a Mendelian inheritance pattern, but is characterized by large-scale mitochondrial DNA (mtDNA) deletions. We have identified two heterozygous missense mutations in the nuclear gene encoding the heart/skeletal muscle isoform of the adenine nucleotide translocator (ANT1) in five families and one sporadic patient. The familial mutation substitutes a proline for a highly conserved alanine at position 114 in the ANT1 protein. The analogous mutation in yeast caused a respiratory defect. These results indicate that ANT has a role in mtDNA maintenance and that a mitochondrial disease can be caused by a dominant mechanism. 相似文献
47.
Johansson L Rytkonen A Bergman P Albiger B Källström H Hökfelt T Agerberth B Cattaneo R Jonsson AB 《Science (New York, N.Y.)》2003,301(5631):373-375
The human-specific bacterial pathogen Neisseria meningitidis is a major cause of sepsis and/or meningitis. The pili of N. meningitidis interact with CD46, a human cell-surface protein involved in regulation of complement activation. Transgenic mice expressing human CD46 were susceptible to meningococcal disease, because bacteria crossed the blood-brain barrier in these mice. Development of disease was more efficient with piliated bacteria after intranasal, but not intraperitoneal, challenge of CD46 transgenic mice, suggesting that human CD46 facilitates pilus-dependent interactions at the epithelial mucosa. Hence, the human CD46 transgenic mice model is a potentially useful tool for studying pathogenesis and for vaccine development against meningococcal disease. 相似文献
48.
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50.
M. v. Cotta M. v. Cotta Mördes v. Pannewib Robert Rühn Paur v. Stelzl v. Deltheim Schulze Q. v. Mikleben Lreiherr v. Lflanteuffel Lreiherr v. Berg Qeitel M. Lreiherr v. Berg v. Michael H. C. Bär Baer A. Chieriod Berger Rettftadt Gekner Wlrici Lreiherr v. Schmerzing Sprenger Pommrich v. Strune Matufchka v. E. Q. Brunft Rnaudt Mördlinger Rnipping v. Mangenheim C. A. Baum L. Mehlborn G. v. Stieglik H. v. Biegefar C. Grebe v.n Baumbach Braun R. Blohmer 《European Journal of Forest Research》1865,9(1):322-324
Ohne Zusammenfassung
f. f?chf. Dberforftmeifter.
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f. preuk. Dberforftmeifter aus Breslau.
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Dberj?germeifter von Braunfchweig.
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grokh. meimar. Forftinfpeftor von Martfuhl.
f. mürttb. Dberf?rfter und Brofeffor aus Hohenheim.
f. hannov. Forftmeifter aus Hammeln.
Dberforftmeifter aus Sotha.
herz. altenburg. Dberf?rfter aus Hummelshain.
herz. altenburg. Revierf?rfter aus Milchwig.
herz. altenburg. geheimer Finanzrath und Dberforftmeifter.
herz. altenb. Dberforftmeifter aus Hummelshain.
grokh. f?chf. geheimer Dberforftrath aus Qifenach.
herz. naffau. Dberforftrath aus Miesbaden.
grokh. heff. Dberforftfefret?r aus Darmftadt.
f. f?chf. Dberforftmeifter. 相似文献