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Metodą elektroforezy bibułowej rozdzielano różne formy selenu. Wyznaczono ruchliwość jonów SeO32- i SeO42-. Wykazano znaczne zróżnicowanie występujących form selenu w badanych roztworach wodnych. Stwierdzono niższą ruchliwość jonu SeO42-.
The aim of this study was to investigate the effect of non-enzymatic glycosylation and hydrolysis of pea albumins with pepsin on their immunoreactive properties. Albumin fraction was isolated from pea seeds an then glycated and hydrolysed by pepsin. Pea albumin was characterised by SDS‑PAGE and glycotest. A 15% progress in non-enzymatic glycosylation was found. The in vivo experiment demonstrated the influence of glycation on mouse mucosal immune system. The influence of native, glycated and hydrolysed pea albumins on spleen (SPL) and mesenteric lymph nodes (MLN) lymphocytes proliferation was investigated. The culture MLN lymphocytes showed an increase in proliferation during stimulation with all of antigens (native, glycated, hydrolyzed). The proliferation was higher in MLN lymphocyte of the intraperitoneally-sensitized group. This observation suggests that the route of immunization can affect their immunoreactivity. SPL lymphocytes of the orally-immunized group showed higher proliferation as compared with SPL lymphocytes of the group sensitized before oral immunization. It is likely that the route of antigen administration has induced a specific food tolerance. The results suggest that none of the modifications performed has changed the immunoreactivity of the investigated proteins to a great extent.
This study investigates the toxic effect of E(2)nonenal (trans-2-nonenal, T2N) and its conjugate with horse muscle myoglobin (Mb) tested on murine cell line L₉₂₉ and human cell line A₅₄₉, as well as the genotoxic effect of these compounds assayed by measuring of micronuclei in human cells K₅₆₂. It is an aldehyde, which is occurring as the substance responsible for an off flavour in aged beers, but originates also from lipid oxidation in heat processed food. T2N is an aldehyde formed from linoleic acid as a secondary oxidation product. The modification of Mb with T2N was analyzed with the use of SDS-polyacrylamide gel electrophoresis (SDS-PAGE), and electrospray ionization mass spectrometry (ESI-MS). Results from SDS-PAGE suggest that T2N substitutes Mb and additionally causes cross-linking with polymerization of Mb resulting in an insoluble fraction. The ESI-MS spectrum of the soluble fraction used in the toxicity tests, demonstrated that conjugation of T2N with Mb yielded Mb adducts with one residue of trans-2-nonenal per myoglobin molecule as the major fraction and adducts with different numbers of T2N molecules as minor fractions. In the cytotoxicity assay the T2N and its Mb conjugate causes 50 % destruction of cells at the concentration 95-125 pg/ml and 200 pg/ml respectively, when L₉₂₉ and A₅₄₉ cell lines were used, whereas Mb control tested up to 2000 mg/ml was without any cytotoxic effect. In genotoxicity in vitro assay we have observed that the T2N and its Mb conjugate expressed the genotoxicity. The number of micronuclei in human K₅₆₂ cells reac₅₆₂ 26 ± 2.16 promille (MN/1000 cells), comparing to 62 ± 8.64 MN/1000 cells for the reference free T2N, whereas a control value was 10.33 ± 1.25 MN/1000 cells. The studied compounds expressed also the apoptotic effect in K₅₆₂ cells as the number of apoptotic cells increased to 44.67 ±4.92 promille for T2N-Mb, comparing to 168.67 ±37.28 promille for free T2N, whereas a control value was 30.33 ± 1.36 promille for Mb. In these assays the T2N-Mb conjugate is several times more toxic in relation to control protein. Results indicate that T2N adducts with protein are potent to induce various cytotoxic and apoptotic effects when assayed in vitro tests. It suggests that higher level of such aldehyde might create in organism severe potential of toxicity.
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The immune response of wheat flour modified by the treatment with subtilisin under different conditions of temperature, incubation periods and the ratio of enzyme/wheat flour was investigated. Respective protein fractions, namely, albumins, globulins, gliadins and glutenins were obtained from the modified wheat flour on the basis of their diverse solubility. The particular wheat protein fractions were examined for the immune reaction by the use of an indirect non-competitive ELISA method. Commercially available antibodies, namely, monoclonal anti-human IgG and monoclonal anti-human IgE conjugates with alkaline phosphatase and human sera with elevated IgG as well as rabbit sera against QQQPP peptide were tested. The highest decrease in gliadins immunoreactivity was observed for wheat flour modified under following conditions: temperature 37°C, 18 h of incubation time and the enzyme/wheat flour ratio of 1:10 000.
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