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排序方式: 共有527条查询结果,搜索用时 15 毫秒
71.
Jinhua Wang Elke Pawelzik Joachim Weinert Qinghua Zhao Gerhard A. Wolf 《European Food Research and Technology》2008,226(6):1365-1371
The Hagberg falling number (HFN) is one of the most important quality characteristics of wheat. Six winter wheat cultivars
from three locations in Germany were analysed to assess the factors influencing the HFN. The cultivars and locations affected
significantly the HFN of all the samples. The infection with Fusarium culmorum, determined in another cultivar, also led to an increase in HFN, which suggested that the HFN method is not adequate enough
for the true determination of the alpha-amylase activity of fungus-infected, wheat flour. Furthermore, there was no clear correlation between HFN and thousand-kernel
weight, starch content or pentosan content. The crude protein content was positively related to the HFN, while the total dietary
fibre content depended on the cultivar and location. 相似文献
72.
Modifications of fruit quality, in response to a long-term salt stress of four months, were studied in two strawberry cultivars differing in their sensitivity to salinity. The sensitive cv. Elsanta and the less sensitive cv. Korona were treated during two vegetation seasons with 0, 40 or 80 mmol NaCl/l in the nutrient solution. While mean fruit weight decreased, dry matter and contents of total soluble carbohydrates, as well as sweetness index of fruits, remained constant. Salt stress in both cultivars increased the antioxidant capacity, antioxidants pools (ascorbic acid, anthocyanins, superoxide dismutase) and selected minerals such as Na+, Cl−, K+, N, P and Zn2+, as well as lipid peroxidation. Furthermore, salt stress increased the contents of free and essential amino acids, especially in cv. Elsanta. The more tolerant cv. Korona was characterized by an increase of reduced glutathione and a better fruit taste. In salt-stressed fruits of cv. Elsanta, taste was significantly impaired. 相似文献
73.
Contribution of amino acids to strawberry fruit quality and their relevance as stress indicators under NaCl salinity 总被引:2,自引:0,他引:2
Strawberry cvs Korona and Elsanta, differing in their sensitivity to salt stress, were exposed to 0, 40, or 80 mM NaCl in the root medium from the end of April to mid-August. Although fruits of both cultivars contained comparable amounts of Na+ and Cl−, fruit quality was more impaired in cv. Elsanta, as indicated by the larger reductions of fruit size and sugar/acid ratios. Malondialdehyde levels started to rise significantly at 40 mM NaCl in the more sensitive cv. Elsanta, but at 80 mM in cv. Korona. Total amino acid levels, especially contents of essential amino acids, rose significantly in both cvs. Salt stress also increased contents of free proline, asparagine, and glutamine. Their increases may contribute to osmotic adjustment. The results of the present study favour the interpretation that elevated levels of proline, asparagine and glutamine are indicative of salt stress damage. 相似文献
74.
75.
Paul C. Rogge Padraic Shafer Gilberto Fabbris Wen Hu Elke Arenholz Evguenia Karapetrova Mark P. M. Dean Robert J. Green Steven J. May 《Advanced materials (Deerfield Beach, Fla.)》2019,31(43)
Interface‐induced modifications of the electronic, magnetic, and lattice degrees of freedom drive an array of novel physical properties in oxide heterostructures. Here, large changes in metal–oxygen band hybridization, as measured in the oxygen ligand hole density, are induced as a result of interfacing two isovalent correlated oxides. Using resonant X‐ray reflectivity, a superlattice of SrFeO3 and CaFeO3 is shown to exhibit an electronic character that spatially evolves from strongly O‐like in SrFeO3 to strongly Fe‐like in CaFeO3. This alternating degree of Fe electronic character is correlated with a modulation of an Fe 3d orbital polarization, giving rise to an orbital superstructure. At the SrFeO3/CaFeO3 interfaces, the ligand hole density and orbital polarization reconstruct in a single unit cell of CaFeO3, demonstrating how the mismatch in these electronic parameters is accommodated at the interface. These results provide new insight into how the orbital character of electrons is altered by correlated oxide interfaces and lays out a broadly applicable approach for depth‐resolving band hybridization. 相似文献
76.
Rianne M. Weggemans Mike Rudrum Elke A. Trautwein 《European Journal of Lipid Science and Technology》2004,106(6):390-397
Several studies have reported a positive association between intake of trans fatty acids and risk of heart disease. It has been suggested that trans fatty acids from ruminant sources are less detrimental than trans fatty acids from industrial sources. Legislation or advice on limiting trans fatty acids has, in some instances, been restricted to trans fatty acids from industrial sources. However, comparisons of ruminant and industrial trans fatty acids have been based on few studies using relative intake data (e.g. quintiles of intakes). Therefore, we have reviewed data describing the associations between absolute intake (g eaten per day) of ruminant and industrial trans fatty acids and risk of coronary heart disease, and examined the associations graphically. Where direct comparison is possible, there are no differences in risk of coronary heart disease between total, ruminant and industrial trans fatty acids for intakes up to 2.5 g/d. At higher intakes (more than 3 g/d) total and industrial trans fatty acids are associated with an increased risk of coronary heart disease but there is insufficient data available on ruminant trans fatty acids at this level of intake. The scarce data do not support discrimination between ruminant and industrial trans fatty acids in dietary recommendations or legislation. 相似文献
77.
Biological Evaluation and X‐ray Co‐crystal Structures of Cyclohexylpyrrolidine Ligands for Trypanothione Reductase,an Enzyme from the Redox Metabolism of Trypanosoma 下载免费PDF全文
Raoul De Gasparo Dr. Elke Brodbeck‐Persch Dr. Steve Bryson Nina B. Hentzen Dr. Marcel Kaiser Prof. Dr. Emil F. Pai Prof. Dr. R. Luise Krauth‐Siegel Prof. Dr. François Diederich 《ChemMedChem》2018,13(9):957-967
The tropical diseases human African trypanosomiasis, Chagas disease, and the various forms of leishmaniasis are caused by parasites of the family of trypanosomatids. These protozoa possess a unique redox metabolism based on trypanothione and trypanothione reductase (TR), making TR a promising drug target. We report the optimization of properties and potency of cyclohexylpyrrolidine inhibitors of TR by structure‐based design. The best inhibitors were freely soluble and showed competitive inhibition constants (Ki) against Trypanosoma (T.) brucei TR and T. cruzi TR and in vitro activities (half‐maximal inhibitory concentration, IC50) against these parasites in the low micromolar range, with high selectivity against human glutathione reductase. X‐ray co‐crystal structures confirmed the binding of the ligands to the hydrophobic wall of the “mepacrine binding site” with the new, solubility‐providing vectors oriented toward the surface of the large active site. 相似文献
78.
Martine Morzel Mary M Heapes William J Reville Elke K Arendt 《Journal of the science of food and agriculture》2000,80(11):1691-1697
The effect of a controlled lactic fermentation on textural and ultrastructural properties of salmon fillets was evaluated. When compared with a non‐inoculated cured sample, fermented salmon had unique textural properties since it exhibited significantly higher force (p < 0.05) and work (p < 0.001) values in a penetration test on two sampling days but a consistently lower hardness (p < 0.05) in a Texture Profile Analysis (TPA) rheological test. Study of the myofibrillar ultrastructure showed that basic structures were drastically damaged during processing and storage of fermented and cured salmon. Nevertheless, Z‐lines were better preserved in fermented samples. It is suggested that the slight protective effect of lactic fermentation with the starter L sake may be the consequence of a lower pH, by putatively inhibiting neutral or alkaline proteolytic enzymes. © 2000 Society of Chemical Industry 相似文献
79.
Harinder P S Makkar Klaus Becker Hj Abel Elke Pawelzik 《Journal of the science of food and agriculture》1997,75(4):511-520
Six colour-flowering (Scirocco, Alfred, Carola, Condor, Tina and Herz Freya) and six white-flowering (Caspar, Albatros, Gloria, Tyrol, Vasco and Cresta) cultivars of Vicia faba were studied. The crude protein contents of colour- and white-flowering cultivars were 267±13·6 and 283±18·8 g kg−1, respectively, which did not differ significantly at P<0·05. The levels of lipids, crude fibre, starch and ash varied from 14 to 22 g kg−1, 88 to 143 g kg−1, 407 to 485 g kg−1 and 32 to 42 g kg−1, respectively. The calculated organic matter digestibility (OMD) and metabolisable energy (ME) of the white-flowering cultivars were significantly higher (P<0·001) than those of the colour-flowering cultivars (OMD: 889·1±26·6 g kg−1 vs 797·5±17·1 g kg−1; ME: 13·97±0·49 vs 12·30±0·34 MJ kg−1). In all cultivars, sulphur amino acids were lower than adequate concentration when compared with recommended amino acid pattern of FAO/WHO/UNO reference protein for a 2–5-year-old child. The in vitro rumen nitrogen degradability of colour-flowering cultivars was significantly lower (P<0·01) compared to that of white-flowering cultivars (71·4±9·3% vs 88·0±11·1%). Amongst colour-flowering varieties, the contents of total phenols (TP), tannins (T) and condensed tannins (CT) were highest in Alfred (28·3, 21·0 and 35·4 g kg−1, respectively). The contents of TP and T were similar (about 15 and 10 g kg−1, respectively) in Carola, Tina and Herz Freya, and the CT were in the order: Condor>Herz Freya>Carola. The CT were not detected in white-flowering varieties, T were virtually absent and TP were extremely low (4·0–4·9 g kg−1). The activities of other antinutritional factors (white- and colour-flowering cultivars, respectively: trypsin inhibitor activity 3·05±0·34 and 1·85±0·09 mg trypsin inhibited g−1; lectin 27·2±9·4 and 27·1±5·1 mg ml−1 assay medium producing haemagglutination; phytate 15·0±2·7 and 16·6±2·3 g kg−1) were very low. A strong negative correlation (r=-0·92, P<0·001) between tannins and in vitro rumen protein degradability was observed which suggested that tannins have adverse effect on protein degradability. Similarly negative correlations between tannin levels and metabolisable energy (r=-0·89; P<0·001) and organic matter digestibility (r=-0·89; P<0·001) were observed. The correlation coefficient between trypsin inhibitor activity and tannins was negative and highly significant (r=-0·88, P<0·001), whereas between tannins and saponins it was significantly positive (r=0·96, P<0·001). ©1997 SCI 相似文献
80.
Emanuele Zannini Deborah M. Waters Elke K. Arendt 《European Food Research and Technology》2014,238(5):763-771
Wheat is primarily used for bread-making. However, fungal diseases, grain moisture at harvest and low-protein contents strongly influence the quality of the wheat flour, thus creating challenges for traders, millers and commercial bakers who struggle to produce consistently high-quality products. This paper address the replacement of low-protein/wholemeal flour functionality for bread-making purposes. Three hydrocolloids, xanthan gum, dextran and hydroxypropyl methylcellulose, were incorporated into bread recipes based on high-protein flours, low-protein flours and coarse wholemeal flour. Hydrocolloid levels of 0–5 % (flour basis) were used in bread recipes to test the water absorption. The quality parameters of dough (farinograph, extensograph, rheofermentometre) and bread (specific volume, crumb structure and staling profile) were determined. Results showed that xanthan had negative impact on the dough and bread quality characteristics. HPMC and dextran generally improved dough and bread quality and showed dosage dependence. Volume of low-protein flour breads were significantly improved by incorporation of 0.5 % of the latter two hydrocolloids. However, dextran outperformed HPMC regarding initial bread hardness and staling shelf life regardless the flour applied in the formulation. 相似文献