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Isoelectric focusing of homogenous arylsulfatase B from human placenta pointed to the presence of enzymatically active and inactive forms of high pi (pH 9-8) and of lower pi (pH 6.5-5.5). Glycan chain analysis performed with the use of a Glycan Differentiation Kit showed that basic forms of arylsulfatase B from human placenta contained mostly high mannose/hybrid type glycans, with 6-O-L-fucose bound to the innermost AT-acetylglucosamine residue, whereas acidic forms of the enzyme contained complex type glycans containing fucose and sialic acid. However, the latter forms constitute a small percentage of the total carbohydrate component. Lectin affinity chromatography of the native enzyme confirmed the presence of a core fucose and a sialic acid.
The non-enzymatic reaction between reducing sugars and proteins, known as glycation, has received increased attention from nutritional and medical research. In addition, there is a large interest in obtaining glycoconjugates of pure well-characterized oligosaccharides for biological research. In this study, glycation of bovine serum albumin (BSA) by d-glucose, d-galactose and d-lactose under dry-heat at 60°C for 30, 60, 120, 180 or 240 min was assessed and the glycated products studied in order to establish their biological recognition by lectins. BSA glycation was monitored using gel electrophoresis, determination of available amino groups and lectin binding assays. The BSA molecular mass increase and glycation sites were investigated by mass spectrometry and through digestion with trypsin and chymotrypsin. Depending on time and type of sugar, differences in BSA conjugation were achieved. Modified BSA revealed reduction of amino groups’ availability and slower migration through SDS/PAGE. d-Galactose was more reactive than d-glucose or d-lactose, leading to the coupling of 10, 3 and 1 sugar residues, respectively, after 120 minutes of reaction. BSA lysines (K) were the preferred modified amino acids; both K256 and K420 appeared the most available for conjugation. Only BSA-lactose showed biological recognition by specific lectins.
Kinetics of amylolytic hydrolysis of autoclaved and extruded potato starch using alpha-amylase and pullulanase mixtures were described. Maltodextrins with dextrose equivalent of 3, 5, 8 and 12 were obtained and their sugar compositions with HPLC method were analyzed. The low molecular sugar (PD 1-2) and oligosaccharide (PD 3-8) contents as well as relationship between dextrose equivalent of maltodextrins and oligosaccharide contents were determined.
The content of carbohydrates soluble in water at 80°C was examined in wheat grain at the stages of incomplete maturity (33 and 40 days from blooming). High content of the carbohydrates was found, which rapidly decreased during grain development. The high-performance liquid chromatography of hot-water extracts showed several percentages of fructose and glucose and many times greater percentages of the oligosaccharides with the retention time above 10 min. After acid hydrolysis, the proportion of fructose in the grain hydrolysates increased to 14 or 39 g/100 g grain and the proportion of the component X, with the retention time about 10 min decreased twice. The increase in the fructose content indicated the presence of fructans which are not fully hydrolysed by acid in the following conditions: HCl concentration 1.65%, temperature of boiling water bath, time 1 h.
Expression as well as properties of integrins are altered upon transformation. Cell adhesion regulated by integrins is modulated by glycosylation, one of the most frequent biochemical alteration associated with tumorogenesis. Characterisation of carbohydrate moieties of alpha3beta1 integrin on the cultured human bladder carcinoma (T-24, Hu456, HCV 29T) and human normal ureter and bladder epithelium (HCV 29, Hu609) cell lines was carried out after an electrophoresis and blotting, followed by immunochemical identification of alpha3 and beta1 integrin chains and analysis of their carbohydrates moieties using highly specific digoxigenin-labelled lectins. In all the studied cell lines alpha3beta1 integrin was glycosylated although in general each subunit differently. Basic structures recognized in beta1 subunit were tri- or tetraantennary complex type glycans in some cases sialylated (T-24, HCV 29, HCV 29T) and fucosylated (Hu609, HCV 29T). Positive reaction with Phaseolus vulgaris agglutinin and Datura stramonium agglutinin suggesting the presence of beta1-6 branched N-linked oligosaccharides was found in cancerous cell lines (T-24, Hu456) as well as in normal bladder epithelium cells (Hu609). High mannose type glycan was found only in beta1 subunit from Hu456 transitional cell cancer line. On the other hand alpha3 subunit was much less glycosylated except the invasive cancer cell line T-24 where high mannose as well as sialylated tri- or tetraantennary complex type glycans were detected. This observation suggests that changes in glycosylation profile attributed to invasive phenotype are rather associated with alpha3 not beta1 subunit.
Transgalactosylation properties of the commercial preparations of beta-galactosidase: Lactase and Maxilact and of the preparation synthesized by Penicillium canescens, were compared.The effect of 2% glucose addition to 20% milk permeate solution on the process of formation of galac- tooligosaccharides during the enzymatic bioconversion of lactose by the examined beta-galactosidase preparations, was also studied. It was found that enzymatic synthesis of galactooligosaccharides in the process of lactose bioconversion was greatly dependent on beta-galactosidase used and that the presence of glucose in lactose solution already at the beginning of hydrolysis was favourable for the formation of oligosaccharides.
The role of the abscisic acid (ABA) in biosynthesis of raffinose family oligosaccharides (RFOs) and galactosyl cyclitols (Gal-C) in tiny vetch (Vicia hirsuta [L.] S.F. Gray) seeds was investigated. The ABA was applied through incubation of seed at various stage of its development. The level of RFOs and Gal-C was determined in seed maturing on plant and in seed maturing in vitro. In early stages of V. hirsuta seed development, the ABA activated the biosynthesis of galactinol, although the level of arisen galactinol quickly declined. In the later stages of V. hirsuta seed development ABA had stimulatory effect of RFOs and Gal-C biosynthesis. Influence of ABA on biosynthesis of a-galactosides in Vicia hirsuta seed seems to be dependent on abscisic acid concentration. Low concentration of ABA had stimulatory effect on a-galactosides biosynthesis, but high concentration of ABA inhibited the process.
A glycan chain analysis of the total oligosaccharide pool derived from rat liver arylsulfatase B was carried out by. P4 Gel Permeation Chromatography and sequential exoglycosidase digestion. It was found that 71% of rat liver arylsulfatase B oligosaccharides were sialylated. The relative contribution of particular structures in the total glycan pool was as follows: sialylated biantennary complex type glycans with terminal galactose--65%, high-mannose type glycans--15%, biantennary complex type glycans with core fucose and terminal N-acetylglucosamine--5%, O-linked oligosaccharides--3.5%.
Ten to 16 ethanol-soluble carbohydrate components were identified in the seeds of six Mexican wild lupins. The analysed carbohydrates included: monosaccharides, disaccharides, cyclitols, galactosyl cyclitols and raffinose family oligosaccharides. Stachyose and sucrose were the main carbohydrate component in the Lupinus montanus, L. rotundiflorus, L. exaltatus, L. mexicanus and L. elegans seeds. Only trace quantities of verbascose were detected in Lupinus mexicanus seeds. The analysed seeds accumulated 38 to 78 mg/g d.m. carbohydrates. The raffinose family oligosaccharides constituted 41 to 85.2% of the identified carbohydrate component pool. The analysed Lupinus seeds contained 3 to 8 unidentified carbohydrate components.
The studies were carried out on 40 female Pharaoh quails. In the fifth week of age, the quails were weighed and randomly assigned to 5 feeding groups. In the group I, control, the females were fed on standard feed formed for adult quail feeding. The experimental groups II and III received the standard mixture with oligosaccharides added, which had been extracted from pea seed, in the quantities and duration, respectively: 0.4 g · kg-1 of mixture for 3 weeks, 0.4 g · kg-1 for the entire period of the experiment, i.e. 4 months. In the groups IV and V, the addition of oligosaccharides was 3 g per kg of feed, with the group IV fed this way for 3 weeks and the group V for 4 months.
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