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41.
Because food ingredients are sometimes considered as causative factors in IgE mediated food allergies, DNA-based tests may prove to be very useful to establish whether allergenic species have been used in foodstuffs production. The development of two SYBR®GreenER™ Real-Time PCR assays, targeting Pru 1 and rbcL genes, based on melting curve analysis, to detect allergen species in food has been presented. Applicability of these methods was assessed with several commercial products containing processed almond.  相似文献   
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The properties of melanoidins prepared from glucose and glycine (GG) were investigated by a three step purification protocol consisting of dialysis, gel filtration at high ionic strength and ion metal affinity chromatography. The high molecular weight fraction obtained in the GG system is responsible for 80% of the total brown colour and its antioxidative ability was about 1/4 of that of Trolox measured by the inhibition of linoleic acid oxidation. GG melanoidins have good affinity towards Cu (II) (32% bound to the resin) while it is much lower towards Pb (II) (10%) and Fe (II) (5%). Capillary zone electrophoresis analysis suggests that GG melanoidins are positively charged, although no signal was observed analysing melanoidins by matrix-assisted laser desorption-ionisation time-of-flight mass spectrometry (MALDI-TOF/MS).  相似文献   
44.
Carotenoids from tomatoes inhibit heterocyclic amine formation   总被引:1,自引:0,他引:1  
Tomatoes are a rich source of antioxidants and they are commonly used for meat cooking in Mediterranean countries. The effects of tomato antioxidants on the formation of carcinogenic/mutagenic heterocyclic amines were investigated. A liquid model system containing as precursors creatinine, glucose and glycine in molar concentrations comparable to those present in bovine meat (chemical model system) was employed. A freeze-dried bovine meat juice (meat juice model system) was also used for some experiments. In both model systems, an inhibiting effect of tomato carotenoid fraction on the formation of imidazoquinolines (IQx, MeIQx and DiMeIQx) was observed. Using carotenoid extract at a concentration of 1000 ppm, inhibitions of 36% and 11% of IQx and MeIQx formation respectively in the chemical system and of 13% of MeIQx and of 5% of 4,8-DiMeIQx in the meat juice system was observed. The effect of the main tomato flavonoid, quercetin, was investigated using the meat juice system. Quercetin gave an inhibition of MeIQx formation between 9% and 57% with a maximum effect of 67% at 10 ppm.  相似文献   
45.
The rapidly increasing data traffic volumes will demand for very high transmission capacity and network nodes throughput. Wavelength division multiplexing (WDM) technology will be asked to support many channels on the same fiber, both in point-to-point links and in WDM optical networks. The transmission of a high number of wavelength channels in all these systems is a key issue. This paper analyzes this topic, in both high capacity links and optical networks, highlighting the impact of fiber non-linearity, and addressing the main source of impairments. This is done through the use of a semi-analytical model recently upgraded to account for all the contributions deriving from Kerr effects, particularly four-wave mixing and cross-phase modulation. The analysis reveals that more than one hundred of channels at 2.5 Gbit/s can be transmitted in point-to-point links whose length can span until the order of 1000 km, and 32 channels per fiber, at the previous bit rate, can be handled in WDM networks, without dispersion compensation. For a higher number of channels (e.g., 64) dispersion compensation is needed.  相似文献   
46.
Producing sprouts directly during space missions may represent an interesting opportunity to offer high-quality fresh ready to eat food to the astronauts. The goal of this work was to compare, in terms of growth and nutritional quality, rocket (Eruca sativa Mill.) seedlings grown in the International Space Station during the ENEIDE mission with those grown in a ground-based experiment (in presence and absence of clinorotation). The rocket seedlings obtained from the space-experiment were thinner and more elongated than those obtained in the ground-based experiment. Cotyledons were often closed in the seedlings grown in the space experiment. Quantitative (germination, fresh and dry weight) and qualitative (glucose, fructose, sucrose and starch) traits of rocket seedling were negatively affected by micrograv-ity, especially those recorded on seedlings grown under real microgravity conditions The total chlorophyll, and carotenoids of seedlings obtained in the space experiment were strongly reduced in comparison to those obtained in the ground-based experiment (presence and absence of clinorotation). The results showed that it is possible to produce rocket seedlings in the ISS; however, further studies are needed to define the optimal environmental conditions for producing rocket seedlings with high nutritional value  相似文献   
47.
Organizations should look at humans as multilayered, not only as professional entities. In synergy, not only individually, we define humans as: (1) physical, (2) mental, (3) social, (4) spiritual, and (5) economic entities, marked by requisitely holistic patterns of relatively permanent characteristics, due to which individuals differ from each other; they differ also as specialized professionals. All these and other attributes form synergies. On this basis, the behavior of individuals who are willing to practice interdisciplinary cooperation becomes socially responsible and they have a high level of well-being.

Individuals as well as organizations seek requisite personal holism (RPH) on the one hand and psychic well-being (PWB) on the other hand. Thus, individuals implement individual techniques and organizations implement special strategies, programs, and actions in the frame of human resource management (HRM). That is how organizations in the frame of HRM, more specifically in the frame of management well-being, are developing special programs for managing PWB. These programs are based on their RPH and organizations might help employees to feel respected and valued in their work settings, without regard to their culture, religion, ethnicity, gender, age, disability, or other individual differences. The most-often applied programs of the kind include: (1) stress management programs, (2) diversity management programs, (3) wellness programs, (4) employee assistance programs, and (5) programs for personal growth.  相似文献   
48.
Bacteriophage infections of starter lactic acid bacteria (LAB) pose a serious risk to the dairy industry. Nowadays, the expanding use of valuable Lactobacillus strains as probiotic starters determines an increase in the frequency of specific bacteriophage infections in dairy plants. This work describes a simple and rapid Polymerase Chain Reaction (PCR) method that detects and identifies bacteriophages infecting Lactobacillus casei/paracasei, the main bacterial species used as probiotic. Based on a highly conserved region of the NTP-binding genes belonging to the replication module of L. casei phages phiA2 and phiAT3 (the only two whose genomes are completely sequenced), a pair of primers was designed to generate a specific fragment. Furthermore, this PCR detection method proved to be a useful tool for monitoring and identifying L. casei/paracasei phages in industrial samples since specific PCR signals were obtained from phage contaminated milk (detection limit: 10(4) PFU/mL milk) and other commercial samples (fermented milks and cheese whey) that include L. casei/paracasei as probiotic starter (detection limit: 10(6) PFU/mL fermented milk). Since this method can detect the above phages in industrial samples and can be easily incorporated into dairy industry routines, it might be readily used to earmark contaminated milk for use in processes that do not involve susceptible starter organisms, or processes which involve phage-deactivating conditions.  相似文献   
49.
Current views of the role of beta-amyloid (Abeta) peptide fibrils range from regarding them as the cause of Alzheimer's pathology to having a protective function. In the last few years, it has also been suggested that soluble oligomers might be the most important toxic species. In all cases, the study of the conformational properties of Abeta peptides in soluble form constitutes a basic approach to the design of molecules with "antiamyloid" activity. We have experimentally investigated the conformational path that can lead the Abeta-(1-42) peptide from the native state, which is represented by an alpha helix embedded in the membrane, to the final state in the amyloid fibrils, which is characterized by beta-sheet structures. The conformational steps were monitored by using CD and NMR spectroscopy in media of varying polarities. This was achieved by changing the composition of water and hexafluoroisopropanol (HFIP). In the presence of HFIP, beta conformations can be observed in solutions that have very high water content (up to 99 % water; v/v). These can be turned back to alpha helices simply by adding the appropriate amount of HFIP. The transition of Abeta-(1-42) from alpha to beta conformations occurs when the amount of water is higher than 80 % (v/v). The NMR structure solved in HFIP/H2O with high water content showed that, on going from very apolar to polar environments, the long N-terminal helix is essentially retained, whereas the shorter C-terminal helix is lost. The complete conformational path was investigated in detail with the aid of molecular-dynamics simulations in explicit solvent, which led to the localization of residues that might seed beta conformations. The structures obtained might help to find regions that are more affected by environmental conditions in vivo. This could in turn aid the design of molecules able to inhibit fibril deposition or revert oligomerization processes.  相似文献   
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