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41.
42.
Søltoft M Bysted A Madsen KH Mark AB Bügel SG Nielsen J Knuthsen P 《Journal of the science of food and agriculture》2011,91(4):767-775
BACKGROUND: The demand for organic food products has increased during the last decades due to their probable health effects, among others. A higher content of secondary metabolites such as carotenoids in organic food products has been claimed, though not documented, to contribute to increased health effects of organic foods. The aim was to study the impact of organic and conventional agricultural systems on the content of carotenoids in carrots and human diets. In addition, a human cross‐over study was performed, measuring the plasma status of carotenoids in humans consuming diets made from crops from these agricultural systems. RESULTS: The content of carotenoids in carrot roots and human diets was not significantly affected by the agricultural production system or year, despite differences in fertilisation strategy and levels. The plasma status of carotenoids increased significantly after consumption of the organic and conventional diets, but no systematic differences between the agricultural production systems were observed. CONCLUSION: The expected higher content of presumed health‐promoting carotenoids in organic food products was not documented in this study. Copyright © 2011 Society of Chemical Industry 相似文献
43.
Susanne Krause Ties Latendorf Hendrik Schmidt Yasemin Darcan‐Nicolaisen Gerald Reese Arnd Petersen Ottmar Janssen Wolf‐Meinhard Becker 《Molecular nutrition & food research》2010,54(3):381-387
Peanut allergy is a major cause of food‐induced severe anaphylactic reactions. To date, no medical care is available to prevent and treat peanut allergy and therefore hypoallergenic peanut varieties are of considerable health political and economic interest. Major allergens that induce IgE‐responses in peanut‐sensitive patients are Ara h 1, Ara h 2 and Ara h 3/4. In order to identify hypoallergenic peanuts, commercially locally available peanut varieties were screened for their allergen content. Ara h 1‐deficient peanuts from Southeast Asia were identified by SDS‐PAGE, immunoblotting, inhibition assays and ELISA. 2‐D PAGE analyses demonstrated the different compositions of the tested extracts and revealed a number of variations of the allergen patterns of peanuts from different varieties. Mediator release experiments of these peanut extracts demonstrated similar allergenicities as compared with standard peanut extract. These results indicate that the allergenicity of peanuts with reduced Ara h 1 content might be compensated by the other allergens, and thus do not necessarily cause a reduction of allergenicity. 相似文献
44.
I. Kruse Ursula Wolfensberger Raphael Badoud K. Eichner 《European Food Research and Technology》1997,205(1):31-38
The formation of CO2 in tomato powder, chosen as an example of a dry culinary product, was investigated at room temperature and at low values
of water activity (a
w). CO2 formation correlated well with parameters that represent the beginning and progression of the Maillard reaction. In the absence
of O2, CO2 formation decreased. Pectin and depolymerized pectin did not influence CO2 formation while galacturonic acid (GalA) had a large effect. Determination of 13CO2 in low-moisture model systems revealed that CO2 was not formed by decarboxylation of GalA alone. Only a small proportion of [1-13C]glycine and GalA was degraded by the Strecker pathway; however, glucose reacted with the labelled amino acid forming 13CO2 which amounted to over 90% of the total CO2 formed. Therefore, CO2 could be used as an early indicator for the beginning of the Maillard reaction in dry culinary products.
Received: 28 October 1996 相似文献
45.
Alexander Prange Nils Kühlsen Barbara Birzele Isolde Arzberger Josef Hormes Susanne Antes Peter Köhler 《European Food Research and Technology》2001,212(5):570-575
The sulfur containing gluten proteins largely determine the baking quality of wheat. In order to probe the speciation of sulfur, gluten proteins [gliadin, high molecular weight (HMW) and low molecular weight (LMW) subunits of glutenin], stored glutenin subunits as well as flour were investigated in situ by S K-edge X-ray near edge absorption structure (XANES) spectroscopy. The spectra confirmed the existence of disulfide bonds in oxidised (oxygen stream) glutenin subunits, supporting their significance for the formation of gluten networks. Additionally, glutenin subunits, which were stored under ambient air and temperature conditions, predominantly contained sulfur of higher oxidation states (sulfoxide, sulfonic acid). The disulfide state and also sulfoxide and sulfonic acid states were detected after reoxidation of glutenin subunits with potassium bromate. 相似文献
46.
Florenza Lüder Ripoli Annika Mohr Susanne Conradine Hammer Saskia Willenbrock Marion Hewicker-Trautwein Silvia Hennecke Hugo Murua Escobar Ingo Nolte 《International journal of molecular sciences》2016,17(5)
Mammary neoplasms are the tumors most affecting female dogs and women. Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable source of archived biological material. Fresh frozen (FF) tissue is considered ideal for gene expression analysis. However, strategies based on FFPE material offer several advantages. Branched-DNA assays permit a reliable and fast workflow when analyzing gene expression. The aim of this study was to assess the comparability of the branched-DNA assay when analyzing certain gene expression patterns between FF and FFPE samples in canine mammary tumors. RNA was isolated from 109 FFPE samples and from 93 FF samples of different canine mammary tissues. Sixteen (16) target genes (Tp53; Myc; HMGA1; Pik3ca; Mcl1; MAPK3; FOXO3; PTEN; GATA4; PFDN5; HMGB1; MAPK1; BRCA2; BRCA1; HMGA2; and Her2) were analyzed via branched-DNA assay (b-DNA). ACTB, GAPDH, and HPRT1 were used as data normalizers. Overall, the relative gene expression of the two different origins of samples showed an agreement of 63%. Still, care should be taken, as FFPE specimens showed lower expression of the analyzed targets when compared to FF samples. The fact that the gene expression in FFPE proved to be lower than in FF specimens is likely to have been caused by the effect of storage time. ACTB had the best performance as a data normalizer. 相似文献
47.
O. B. Jrgensen L. G. Karlsen N. B. Nielsen S. Pedersen Susanne Rugh 《Starch - St?rke》1988,40(8):307-313
The properties of a new immobilized glucose isomerase, produced by a selected strain of Streptomyces murinus, are described. The major advantages of the new immobilized enzyme are a productivity of more than 10,000 kg syrup dry substance per kg enzyme under optimal industrial conditions, increased activity and a very low syrup by-product formation. The influence of process parameters (temperature, pH and feed syrup additives) on activity and stability is discussed based on laboratory and industrial plant data. 相似文献
48.
Susanne Zinckgraf 《工程塑料应用》2007,35(5):插3
亲爱的读者: 欧洲与中国正彼此靠拢,越来越多的公司穿梭往来于两地之间.数量众多的来自德国、奥地利和瑞士的塑料及橡胶工业的供应商也加入到这股潮流之中.对他们而言,中国是最重要的销售市场之一. 相似文献
49.
Hussein Farah Susanne N. Wijesinghe Thomas Nicholson Fawzeyah Alnajjar Michelangelo Certo Abdullah Alghamdi Edward T. Davis Stephen P. Young Claudio Mauro Simon W. Jones 《International journal of molecular sciences》2022,23(6)
Changes in cellular metabolism have been implicated in mediating the activated fibroblast phenotype in a number of chronic inflammatory disorders, including pulmonary fibrosis, renal disease and rheumatoid arthritis. The aim of this study was therefore to characterise the metabolic profile of synovial joint fluid and synovial fibroblasts under both basal and inflammatory conditions in a cohort of obese and normal-weight hip OA patients. Furthermore, we sought to ascertain whether modulation of a metabolic pathway in OA synovial fibroblasts could alter their inflammatory activity. Synovium and synovial fluid was obtained from hip OA patients, who were either of normal-weight or obese and were undergoing elective joint replacement surgery. The synovial fluid metabolome was determined by 1H NMR spectroscopy. The metabolic profile of isolated synovial fibroblasts in vitro was characterised by lactate secretion, oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) using the Seahorse XF Analyser. The effects of a small molecule pharmacological inhibitor and siRNA targeted at glutaminase-1 (GLS1) were assessed to probe the role of glutamine metabolism in OA synovial fibroblast function. Obese OA patient synovial fluid (n = 5) exhibited a different metabotype, compared to normal-weight patient fluid (n = 6), with significantly increased levels of 1, 3-dimethylurate, N-Nitrosodimethylamine, succinate, tyrosine, pyruvate, glucose, glycine and lactate, and enrichment of the glutamine–glutamate metabolic pathway, which correlated with increasing adiposity. In vitro, isolated obese OA fibroblasts exhibited greater basal lactate secretion and aerobic glycolysis, and increased mitochondrial respiration when stimulated with pro-inflammatory cytokine TNFα, compared to fibroblasts from normal-weight patients. Inhibition of GLS1 attenuated the TNFα-induced expression and secretion of IL-6 in OA synovial fibroblasts. These findings suggest that altered cellular metabolism underpins the inflammatory phenotype of OA fibroblasts, and that targeted inhibition of glutamine–glutamate metabolism may provide a route to reducing the pathological effects of joint inflammation in OA patients who are obese. 相似文献
50.
Nadine Jaeckels Stefan Tenzer Susanne Rosfa Hansjoerg Schild Heinz Decker Petra Wigand 《Food chemistry》2013
Lipid transfer proteins (LTP) play a major role in plant defence and are of particular interest due to their known ability to cause allergic reactions. These proteins are expressed in grapes and also remain detectable after vinification, especially in red wine. However, it remains unknown whether the protein undergoes any changes during the vinification process. Here, we present a purification method for LTPs from Dornfelder grapes and wine. By liquid-chromatography–mass spectroscopy (LC–MS/MS) we identified LTPs from two different species (Vitis vinifera and Vitis aestivalis). Additionally, the purified LTPs were characterised using spectrometric methods, confirming their high purity and structural stability during vinification. We conclude that LTPs are resistant to the alcohol content (13.5 vol%), acidic milieu of wine and other ingredients present during the vinification process, indicating that the allergenic potential of grape LTP is not diminished by the vinification process. 相似文献