scholarly journals Microanalysis Characterization of Bioactive Protein-Bound Polysaccharides Produced by Amanita Ponderosa Cultures

2014 ◽  
Vol 21 (1) ◽  
pp. 84-90 ◽  
Author(s):  
Cátia Salvador ◽  
M. Rosário Martins ◽  
A. Teresa Caldeira
Keyword(s):  
Accelerated Aging ◽  
Artemia Salina ◽  
Quercus Suber ◽  
Attenuated Total Reflection ◽  
Biologically Active ◽  
Edible Mushrooms ◽  
Size Exclusion ◽  
Molecular Weights ◽  
Exclusion Chromatography ◽  
Biotechnological Processes

AbstractDifferent compounds of edible mushrooms are responsible for their bioactivity. The ability to synthesize polysaccharides, namely protein–polysaccharide (PPS) complexes, is related to the antioxidant capacity of these compounds and present great interest in preventing a number of diseases, including cancer, cardiovascular and auto-immune diseases, and accelerated aging. Amanita ponderosa are wild edible mushrooms that grow in Mediterranean “montado” areas [Portuguese name given to cork oak (Quercus suber) and holm oak (Quercus ilex) forests]. The aim of this study was to evaluate the production of PPS complexes obtained from A. ponderosa cultures using a new microanalytical approach to quickly and easily monitor the production process. Microanalysis using Fourier-transform infrared using attenuated total reflection and Raman spectroscopy of PPS samples showed spectra compatible with identification of this type of compound in culture extracts. PPS separated by size-exclusion chromatography showed seven main complexes. Molecular weights of the main PPS complexes isolated from cultures ranged between 1.5 and 20 kDa and did not present toxicity against Artemia salina, demonstrating the potential of A. ponderosa as a source of biologically active compounds with nutraceutical value. Application of this microanalytical approach to monitoring the production of PPS compounds can be successfully applied in biotechnological processes.

Characterisation of Persistent Anti-Xa Activity Following Administration of the Low Molecular Weight Heparin Enoxaparin Sodium (Clexane)

1994 ◽  
Vol 72 (02) ◽  
pp. 275-280 ◽  
Author(s):  
David Brieger ◽  
Joan Dawes
Keyword(s):  
Molecular Weight ◽  
Enoxaparin Sodium ◽  
Antithrombin Iii ◽  
Anticoagulant Activity ◽  
Active Material ◽  
Biologically Active ◽  
Size Exclusion ◽  
Low Molecular Weight ◽  
Exclusion Chromatography ◽  
Liver And Kidney

SummaryIt is widely reported that persistent anti-Xa activity follows administration of low molecular weight heparins. To identify the effectors of this activity we have injected 125I-labelled Enoxaparin sodium into rabbits and subsequently analysed the circulating radiolabelled material and anti-Xa activity by affinity and size exclusion chromatography. Antithrombin III-binding material derived from the injected drug was responsible for all the anti-Xa amidolytic activity. At early times after injection additional anticoagulant activity which was largely attributable to tissue factor pathway inhibitor was measured by the Heptest clotting assay after removal of glycosaminoglycans from plasma samples. Small radiolabelled fragments, including penta/hexasaccharide with affinity for antithrombin III, were detectable in the circulation 1 week later, and sulphated oligosaccharides persisted for 3-4 weeks. Significant quantities of radiolabel remained in the liver and kidney several weeks post-injection; these organs may sequester some of the injected drug and give rise to circulating biologically active material by degradation and secretion of catabolic products into the plasma.

Synthesis and characterization of new, liquid, branched poly(methylvinylborosiloxanes)

e-Polymers ◽  
2013 ◽  
Vol 13 (1) ◽  
Author(s):  
Jerzy Chruściel ◽  
Marzena Fejdyś ◽  
Witold Fortuniak
Keyword(s):  
Functional Groups ◽  
Atomic Spectroscopy ◽  
Size Exclusion ◽  
Random Structure ◽  
Molecular Weights ◽  
Chemical Structures ◽  
Siloxane Oligomers ◽  
Exclusion Chromatography ◽  
Ether Solution

Abstract New liquid branched poly(methylvinylborosiloxanes) (br-PMVBS) of random structure were synthesized in three steps. By reacting boric acid with an excess of dimethyldichlorosilane (Me2SiCl2) in dry ether a “borosiloxane precursor”: tris(chlorodimethylsilyl) borate B(OSiMe2Cl)3 was prepared. In the second step of synthesis ether solution of B(OSiMe2Cl)3 was added to a mixture of appropriate organic chlorosilanes (Me2SiCl2, MeViSiCl2, MeSiCl3, and Me3SiCl) and all reagents were reacted with stoichiometric amounts of water, in the presence of pyridine (as an acceptor of HCl), in dry ether, at low temperature (usually at -10 to 0 C). In order to fully react (“to block”) trace silanol groups, reactions of intermediate PMVBS with additional batches of Me3SiCl were carried out in the third step, C5H5N·HCl was filtered off and washed with a dry ether. The solvent was distilled off from filtrates and low molecular weight siloxane oligomers were removed by a vacuum distillation at 130-150 C. Chemical structures of br-PMVBS were confirmed by elemental analysis and spectroscopic methods (FTIR, emission atomic spectroscopy ICP-AES, and NMR: 1H, 29Si and 11B). On the basis of analysis of their 29Si-NMR spectra the microstructure of polysiloxane chains was proposed. The prepared br-PMVBS had in their structures: triple branching borosiloxane units: BO1.5 and in some cases methylsiloxane moiety CH3SiO1.5 (T). They contained linkages: Si-O-Si, Si-O-B, vinyl(methyl)siloxane functional groups (CH2=CH)MeSiO (Dvi), dimethylsiloxane mers (CH3)2SiO (D), and non-reactive trimethylsiloxy terminal groups (CH3)3SiO0.5 (M), but they did not have: hydroxyl functional groups: Si-OH and B-OH, and sensitive to water B-O-B linkages. Molecular weights of br-PMVBS (Mn = 1500-3300 g/mol; Mw = 3800-7400 g/mol) and their polydispersity (Mw/Mn = 2.0-2.5) were determined by a size exclusion chromatography (SEC).

scholarly journals Characterization of a monoclonal antibody directed against the biologically active site of human interleukin 1.

1986 ◽  
Vol 163 (2) ◽  
pp. 463-468 ◽  
Author(s):  
A Köck ◽  
M Danner ◽  
B M Stadler ◽  
T A Luger
Keyword(s):  
Monoclonal Antibody ◽  
Active Site ◽  
Biological Effects ◽  
Interleukin 1 ◽  
Biologically Active ◽  
Size Exclusion ◽  
Fibroblast Proliferation ◽  
Initial Activity ◽  
Exclusion Chromatography

Human IL-1 was successfully used to produce an anti-IL-1 mAb. Anti-IL-1 (IgG2a) blocked IL-1-mediated thymocyte and fibroblast proliferation, but did not interfere with the biological effects of other lymphokines, such as IL-2 or IL-3. The antibody immunoprecipitated biosynthetically radiolabeled 33, 17, and 4 kD IL-1. An immunoadsorbent column yielded 20% of initial activity, and upon HPLC size-exclusion chromatography, affinity-purified IL-1 had a molecular mass of approximately 4 kD. These results provide first evidence of a monoclonal anti-IL-1 that reacts with different species of IL-1 and apparently binds to an epitope close to the active site of IL-1. Thus, anti-IL-1 IgG may be very helpful for further investigations of the molecular as well as biological characteristics of IL-1 and related mediators.

Comparison of exopolysaccharides from mucoid and nonmucoid strains of Clavibacter michiganensis subspecies sepedonicus

1993 ◽  
Vol 39 (3) ◽  
pp. 291-296 ◽  
Author(s):  
Paul J. Henningson ◽  
Neil C. Gudmestad
Keyword(s):  
Molecular Weight ◽  
High Performance ◽  
Size Exclusion ◽  
Enzyme Linked Immunosorbent Assay ◽  
Low Molecular Weight ◽  
Neutral Sugar ◽  
Clavibacter Michiganensis ◽  
Serological Reaction ◽  
Molecular Weights ◽  
Exclusion Chromatography

The exopolysaccharides produced by six strains of Clavibacter michiganensis ssp. sepedonicus were isolated and purified by liquid chromatography. Neutral sugar composition and molecular weights were determined for each polysaccharide fraction, using gas chromatography and high-performance size-exclusion chromatography. The serological reaction of each fraction was tested using enzyme-linked immunosorbent assay. Exopolysaccharide from nonmucoid strains contained only low molecular weight polysaccharides (1.5 × 103 to 1.1 × 104). Exopolysaccharide from mucoid and intermediate strains could be separated into low (4.0 × 103 to 1.1 × 104) molecular weight and high (5.0 × 105 to 1.6 × 106) molecular weight fractions. High molecular weight polysaccharides were composed almost exclusively of galactose, glucose, and fucose. The ratios of these sugars were highly variable among strains. Low molecular weight polysaccharides were primarily composed of galactose with significant and varying amounts of glucose, rhamnose, mannose, and ribose. All polysaccharide fractions except one, produced by a nonmucoid strain, reacted in the immunoassay test.Key words: exopolysaccharide, polysaccharide, Clavibacter, michiganensis, sepedonicus.

Relationships between Molecular Weights and Rheological Properties of Asphalts

1996 ◽  
Vol 1535 (1) ◽  
pp. 10-14 ◽  
Author(s):  
Jan F. B ranthaver ◽  
Raymond E. Robertson ◽  
John J. Duvall
Keyword(s):  
Molecular Weight ◽  
Rheological Properties ◽  
Size Exclusion Chromatography ◽  
Size Exclusion ◽  
Molecular Weights ◽  
Molecular Weight Distributions ◽  
Molecular Associations ◽  
Weight Distributions ◽  
Exclusion Chromatography ◽  
Microstructural Model

It is known that the rheological properties of mixtures of organic compounds are functions of molecular weight distributions. However, with respect to asphalts, which are composed of many different compounds and compound types, molecular weights are difficult to measure. This difficulty occurs because the molecular associations that form are held together by forces of varying strengths and are partly broken up by heat and solvents. In theory, the strongest molecular associations in asphalts should have the greatest influence on the rheological properties of asphalts. These associations would be expected to be the major contributors to the asphalt's behaving as if it were a relatively high molecular weight material. Asphalt molecular associations should be isolatable by means of size exclusion chromatography. Several fractions of varying molecular weights (measured by membrane osmometry and vapor phase osmometry) were isolated from Strategic Highway Research Program (SHRP) asphalt AAD-1 by preparative size exclusion chromatography. Molecular weights of these fractions ranged from approximately 2,000 daltons to over 40,000 daltons. When these fractions were independently mixed with asphalt AAD-1 solvent moiety, mixtures were obtained whose rheological properties were a function of the molecular weights and concentrations of the associated materials. These results support the microstructural model of asphalt proposed during SHRP. The results also suggest that the unusual rheological properties of some asphalts may be explained by measuring molecular weight distributions. This type of information may be useful for modification of asphalts to achieve desirable rheological properties.

Characterization of dissolved organic matter from Australian and Chinese source waters by combined fractionation techniques

2011 ◽  
Vol 64 (1) ◽  
pp. 171-177 ◽  
Author(s):  
Qunshan Wei ◽  
Rolando Fabris ◽  
Christopher W. K. Chow ◽  
Changzhou Yan ◽  
Dongsheng Wang ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
High Performance ◽  
Size Exclusion ◽  
Rapid Urbanization ◽  
Molecular Weights ◽  
Treatment Processes ◽  
Exclusion Chromatography ◽  
Urbanization In China ◽  
Source Waters

The character of dissolved organic matter (DOM) in source waters from two countries (Australia and China) was investigated using an extended fractionation technique by combining resin adsorption, ultrafiltration and high performance size exclusion chromatography. There are distinctive chemical characteristics associated with DOM origins. Australian sourced DOM had higher hydrophobic acid (HoA) content and exhibited a more pronounced humic character, indicating a higher influence from allochthonous organics (decayed plant bodies from vegetated catchments). The higher content of hydrophobic base and neutral components found in Chinese DOM, may be attributed to the effects of increasing pollution caused by the rapid urbanization in China. The molecular weights (MWs) of aquatic HoA are predominantly in the moderate (e.g. 1–10 kDa) or small (e.g. <1 kDa) ranges. This suggests that aquatic HoA should not be assumed as high MW organics without experimental validation. It is also found that some of the low MW compounds in our samples were hydrophobic, which could explain the observation of low MW organic compounds being able to be removed by conventional treatment processes.

scholarly journals Towards Novel Fluorinated Methacrylic Coatings for Cultural Heritage: A Combined Polymers and Surfaces Chemistry Study

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1190 ◽  
Author(s):  
Valentina Sabatini ◽  
Eleonora Pargoletti ◽  
Valeria Comite ◽  
Marco Aldo Ortenzi ◽  
Paola Fermo ◽  
...  
Keyword(s):  
Prolonged Exposure ◽  
Accelerated Aging ◽  
Water Repellency ◽  
Size Exclusion ◽  
Butyl Methacrylate ◽  
Capillary Absorption ◽  
Scanning Calorimetry ◽  
Water Contact ◽  
Coated Materials ◽  
Exclusion Chromatography

In this work, new co- and ter-polymers of methyl methacrylate (MMA), ethyl methacrylate (EMA), and N-butyl methacrylate (nBuMA), containing just 1% mol × mol−1 of a fluorinated co-monomer, 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-octyl methacrylate (POMA), were synthesized. After an UV accelerated aging test, the photo-chemical stability of the polymers prepared was determined by 1H NMR and FT-IR spectroscopy, size exclusion chromatography, differential scanning calorimetry and wettability measurements. The polymers were applied to Botticino tiles to achieve better performances in terms of water repellency and consequently deterioration resistance. One-year prolonged exposure to a real environment was conducted and the properties of the coated materials and their performances were studied using different surface techniques such as water contact angle (WCA) and colorimetric measurements (CIELaB), capillary absorption, permeability (RVP) tests and soluble salts determination. The effectiveness of the fluorinated methacrylic coatings was clearly demonstrated; among all the resins, the co-polymer MMA_POMA seems to be the most performing one. Furthermore, both the UV photo-chemical resistance and the easiness of removal was successfully studied.

scholarly journals Analysis of Network Structures in Thiol-Ene UV Curing System Using Reworkable Resins

Polymers ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 5 ◽  
Author(s):  
Haruyuki Okamura ◽  
Masashi Yamagaki ◽  
Kyohei Nakata
Keyword(s):  
Chain Length ◽  
Uv Curing ◽  
Size Exclusion ◽  
Network Structures ◽  
Thiol Compounds ◽  
Molecular Weights ◽  
Degraded Samples ◽  
Exclusion Chromatography ◽  
Chain Lengths ◽  
Acrylate Monomers

An analysis of the network structures in thiol-ene UV curing resins was carried out using reworkable resins composed of di(meth)acrylate monomers having tertiary ester linkages. The effect of the functionality of the thiols, the functional ratio of the thiol and ene functions, their conversions and curing atmosphere on the chain lengths was discussed. A mixture of (meth)acrylates, thiol compounds, a photoradical initiator, and a photoacid generator was cured by irradiation at 365 nm. The cured samples were degraded by heating after irradiation at 254 nm. Size exclusion chromatography (SEC) and 1H NMR analyses of the degraded samples were carried out after the methylation. The crosslinking conditions strongly affected the network structures. The degraded samples have molecular weights between 250 and 2700. The molecular weights of the degraded resins increased with the functionality of the thiol compounds. The chain length dependence suggests that thiol compounds with a high functionality have a low reactivity due to steric hindrance. The chain lengths of the degraded networks were nearly proportional to the concentration of the (meth)acrylate monomers. The addition of reactive diluents enhanced the reactivity and increased the chain length.

scholarly journals Synthesis and Characterization of an Iron-Containing Fatty Acid-Based Ionomer

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
David A. Stone ◽  
Atanu Biswas ◽  
Zengshe Liu ◽  
Veera Boddu ◽  
H. N. Cheng
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Raw Materials ◽  
Low Cost ◽  
Paper Industry ◽  
Alder Reaction ◽  
Size Exclusion ◽  
Molecular Weights ◽  
Exclusion Chromatography ◽  
Solid Film

One of the desirable research goals today is to convert agro-based raw materials into low-cost functional polymers. Among the readily available natural raw materials are the fatty acids that can be obtained from the hydrolysis of plant oils or from the paper industry as byproducts. In this work, a novel iron-containing ionomer has been prepared through the reaction of fatty acids with steel dust or iron powder in the presence of carbon dioxide and water. Characterization has been achieved via 1H and 13C NMR, FT-IR, and size exclusion chromatography. The product has been shown to have an ionomeric structure, consisting of oligomers of fatty acid carboxylates (derived from Diels-Alder reaction) coupled with iron(II) and iron(III) ions (from the oxidation of iron). Because the fatty acid oligomers have low molecular weights, the ionomer easily dissolves in a solvent and can be made into different physical forms, such as liquid, solid, film, or foam.

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