scholarly journals Studies on the structure of hyaluronic acid. Characterization of the product formed when hyaluronic acid is treated with ascorbic acid

1969 ◽  
Vol 114 (4) ◽  
pp. 819-825 ◽  
Author(s):  
David A. Swann
Keyword(s):  
Ascorbic Acid ◽  
Hyaluronic Acid ◽  
Sedimentation Equilibrium ◽  
Connective Tissues ◽  
Molecular Weights ◽  
The Matrix ◽  
Molecular Sizes ◽  
Equilibrium Analyses ◽  
Physical And Chemical

Physical and chemical methods were used to characterize hyaluronic acid before (fraction HAIIBI) and after (fraction HA-AA) treatment with ascorbic acid. Fraction HA-AA was recovered with an almost quantitative yield and was shown to be chemically identical with fraction HAIIBI by all the methods used. These two materials, however, differed markedly in their molecular sizes and degree of polydispersity. By using sedimentation, diffusion and sedimentation-equilibrium analyses, weight-average molecular weights of about 1·2×106 and 6·5×104 respectively were obtained for fractions HAIIBI and HA-AA. It is concluded from these results that hyaluronic acid has a molecular weight of about 65000 and that the polysaccharide chain of this molecule is not depolymerized by ascorbic acid. It is further proposed that hyaluronic acid molecules in the matrix of connective tissues are present either in an aggregated form or as subunits of heterogeneous macromolecules, and that it is the linkages responsible for the organization of these structures which are broken by ascorbic acid.

The Isolation and Characterization of a Ternary Human Plasmin B-Chain-Streptokinase-Plasminogen Complex

1987 ◽  
Vol 58 (02) ◽  
pp. 772-777 ◽  
Author(s):  
Louis Summaria ◽  
Irena Boreisha ◽  
Grant H Barlow ◽  
Kenneth C Robbins
Keyword(s):  
Ternary Complex ◽  
Double Diffusion ◽  
Sedimentation Equilibrium ◽  
Molar Ratio ◽  
Molecular Weights ◽  
Isolation And Characterization ◽  
Human Plasminogen ◽  
Equilibrium Analyses ◽  
Species Specific

SummaryA ternary equimolar human plasmin B-chain-streptokinase-plasminogen complex was isolated from a mixture of the plasmin B-chain-streptokinase complex and human plasminogen at 0° C and 37° C. A ternary complex which was shown to be species specific, was identified and characterized by ultracentrifugal, acrylamide gel electrophoretic, and agarose double diffusion analyses. When mixed at a 1:1 molar ratio at 0° C, 39.9% of the preparation existed as a plasmin B-chain-streptokinase-plasmino-gen complex; when mixed at 37° C, 86.d% existed as a complex, which was identified by electrophoretic analyses to be a plasmin B-chain-streptokinase-plasmin complex. Sedimentation velocity analyses gave s°2o,w values of 3.79 for the plasmin B-chain-streptokinase complex, 4.10 for Lys-plasmin, and 6.23 for the plasmin B-chain-streptokinase-plasmin complex. Sedimentation equilibrium analyses gave molecular weights of 73,900 for the plasmin B-chain-streptokinase complex, 82,900 for Lys-plasmin, and 153,100 for the plasmin B-chain-streptokinase-plasmin complex. The diisopropylphosphorofluoridatc (DFP)-inhibitcd and the p-nitrophenyl-p-guanidino-benzoate (NPGB)-inhibited plasmin B-chain-streptokinase complexes both retained their ability to form a ternary complex with human plasminogen, but this complex did not convert to a plasmin B-chain-streptokinase-plasmin complex. Thus, the active site serine residue is essential for the activator activity of the plasmin B-chain-streptokinase complex, but it is not necessary for the binding of the plasmin B-chain-streptokinase complex to plasminogen to form a ternary complex.

Characterization of Hyaluronic Acid-Poly(Ethylene Oxide) Hydrogel Dependent upon Poly(Ethylene Oxide)

2007 ◽  
Vol 342-343 ◽  
pp. 749-752
Author(s):  
Mi Sook Kim ◽  
Yoon Jeong Choi ◽  
Gun Woo Kim ◽  
In Sup Noh ◽  
Yong Doo Park ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Ethylene Oxide ◽  
Thiol Groups ◽  
Molecular Weights ◽  
Hydrogel Network ◽  
End Groups ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Surface Morphologies

Characterization of an hyaluronic acid (HA)-poly(ethylene oxide) (PEO) hydrogel was performed by changing the number of side arms in a PEO molecule. Verification of grafting chemistry and mechanical strength, as well as swelling behaviors and surface morphologies of the HA-PEO hydrogels were analyzed by employing different x-linking molecular weights (MW) of PEO ranging from 1.7 to 5.0 kDa at a fixed low MW HA in the hydrogel network. Methacrylation to the HA successfully obtained via Michael type reaction between the methacrylate arm groups in HA and the thiol end groups in PEO was observed by XPS. Hydrogel formation was markedly dependent upon the numbers of thiol groups in the PEO molecule. Furthermore the lower MW PEO-based HA hydrogel demonstrated stronger mechanical properties but lower water absorption and the smaller pore sizes on its surface and cross section.

scholarly journals Properties of allophycocyanin II and its α- and β-subunits from the thermophilic blue–green alga Mastigocladus laminosus

1979 ◽  
Vol 181 (3) ◽  
pp. 577-583 ◽  
Author(s):  
Jürg R. Gysi ◽  
Herbert Zuber
Keyword(s):  
Gel Filtration ◽  
Fluorescence Emission ◽  
Potassium Phosphate ◽  
Difference Spectrum ◽  
Spectroscopic Properties ◽  
Sedimentation Equilibrium ◽  
Visible Absorption ◽  
Molecular Weights ◽  
Α And Β Subunits ◽  
Equilibrium Analyses

Purified allophycocyanin II and its subunits have been examined with respect to spectroscopic properties, sedimentation, reconstitution and isoelectric behaviour. In 0.02m-potassium phosphate buffer, pH8.0, and at a concentration of 0.25mg/ml, allophycocyanin II and its α- and β-subunits show visible absorption maxima at 650, 615 and 615nm respectively, whereas the fluorescence emission maxima were determined to be at 662, 640 and 630nm respectively. The absorption difference spectrum (dilution difference) of allophycocyanin II displays maxima at 650 and 590nm with a minimum at 610nm. The c.d. spectrum of allophycocyanin II showed only one positive-ellipticity band at 635nm, and a major negative-ellipticity band at 340nm. Oxidation of allophycocyanin II, low- and high-pH solutions (pH3.0 and 11.0), various ethanol concentrations as well as dialysis against distilled water induce a spectral change leading to phycocyanin-like characteristics. In most cases these shifts are reversible. Allophycocyanin II is thermostable over a period of 60min at temperatures up to 60°C. The isoelectric points of allophycocyanin II and its α- and β-subunits are 4.65, 4.64 and 4.82 respectively. Estimated molecular weights from sedimentation-equilibrium analyses were 102500 for allophycocycanin II, 16000 for the α- and 31500 for the β-subunit. Recombination of α- and β-subunits leads to allophycocyanin II, which is indistinguishable from native allophycocyanin with respect to its spectral form, to its gel-filtration and to its electrophoretic behaviour.

scholarly journals OBTENÇÃO E CARACTERIZAÇÃO DOS PRINCIPAIS PRODUTOS DO CAJU

2004 ◽  
Vol 22 (1) ◽  
Author(s):  
ANTÔNIO CALIXTO LIMA ◽  
NELSON HORACIO PEZOA GARCÍA ◽  
JANICE RIBEIRO LIMA
Keyword(s):  
Fatty Acids ◽  
Ascorbic Acid ◽  
Oleic Acid ◽  
Dietary Fiber ◽  
Unsaturated Fatty Acids ◽  
Ascorbic Acid Content ◽  
Total Dietary Fiber ◽  
Cashew Nut ◽  
Physical And Chemical

A presente pesquisa teve por objetivo a obtenção e caracterização de produtos derivados do caju. Para tanto, produtos da castanha-de-cajueiro comum e do pedúnculo de caju do clone CCP76 foram processados e submetidos a análises físicas e químicas. Mediante prensagem da amêndoa de castanha-de-caju obtevese a torta parcialmente desengordurada (36,41% de proteínas, 26,57% de lipídios totais e 7,86% de fibra digestiva total) e o óleo (82,74% de ácidos graxos insaturados, predominando o ácido oléico - 60,30% e o linoléico - 21,53%). Do pseudofruto do caju foi obtido o suco clarificado e concentrado a vácuo (teor de ácido ascórbico de 966,13 mg/100 g de suco) e a fibra de caju (61,21% de fibra digestiva total). Concluiu-se que os produtos originários do caju apresentam elevado potencial para a elaboração de diferentes produtos alimentícios em virtude da diversidade e riqueza na composição química da castanha e do seu pseudofruto. OBTENTION AND CHARACTERIZATION OF THE MAIN CASHEW PRODUCTS Abstract The objective of the present research was the obtention and the characterization of cashew derived products. For that, products of common cashew nut and from the peduncles of cashew from the clone CCP76 were processed and submitted to physical and chemical analysis. By pressing the cashew nut it was obtained a partially defatted meal (36.41% of proteins, 26.57% of lipids and 7.86% total dietary fiber) and the oil (82.74% of unsaturated fatty acids, predominantly oleic acid - 60.30% and the linoleic - 21.53%). From cashew fruit it was obtained a clarified and concentrated juice (ascorbic acid content of 966.13 mg/100 g of juice) and cashew fiber (61.21% of total dietary fiber). It was concluded that the products originated from cashew showed high potential for the elaboration of different food products by virtue of the diversity and richness of the cashew nut and fruit chemical composition.

PROPRIETES CHIMIQUES ET PHYSIQUES DE LA MATIERE ORGANIQUE NONDIALYSABLE EXTRAITE DE QUATRE PODZOLS DU QUEBEC

1972 ◽  
Vol 52 (1) ◽  
pp. 1-17 ◽  
Author(s):  
ANTONIO GONZALEZ ◽  
GÉRARD HUBERT
Keyword(s):  
Chemical Properties ◽  
Great Similarity ◽  
Metallic Ions ◽  
Carbon And Nitrogen ◽  
Molecular Weights ◽  
Carbon And Nitrogen Content ◽  
Physical And Chemical ◽  
Humic Fractions ◽  
Molecular Weight Fractions

The physical and chemical properties of non-dialysable (>48 A) humic and fulvic fractions of four podzols from the Province of Quebec were studied. Extraction was made with 0.1 M sodium pyrophosphate. Analysis of the fractions showed that, in spite of a prolonged dialysis, considerable quantities of metallic ions remained bound to compounds of high molecular weights. The humic fraction showed, in general, a carbon and nitrogen content sensibly more even than the fulvic fraction. In the spodic horizon, humic fractions have a very similar carbon content. It is also in this horizon that are found the highest percentages of iron and aluminium. The distribution of the principal nitrogen compounds in each fraction was studied after acid hydrolysis. A great similarity in the distribution of the nitrogen was found, independently of its origin (horizon or profile). It has not been possible to find a relation between profiles, from the study of acid groups (carboxilic or phenolic). Absorption spectra with ultraviolet, visible, and infrared radiations were studied. The characterization of a profile from optical properties of high molecular weight fractions was particularly difficult, considering the great similarity between observed spectra. Differences in iron bound to the fulvic fraction were observed by means of electrophoresis. The behaviour of the humic and fulvic fractions towards H+ and Ca2+ ions was also studied.

scholarly journals CHARACTERIZATION OF THE EXTERNAL PROTEINS OF HAMSTER FIBROBLASTS

1974 ◽  
Vol 62 (2) ◽  
pp. 438-448 ◽  
Author(s):  
Richard O. Hynes ◽  
Kenneth C. Humphryes
Keyword(s):  
Hyaluronic Acid ◽  
Cell Lines ◽  
Fibroblast Cell ◽  
Transformed Cells ◽  
Metabolic Labeling ◽  
Polyacrylamide Gels ◽  
Molecular Weights ◽  
Fibroblast Cell Lines

The results of metabolic labeling studies and enzymatic treatments followed by analysis on polyacrylamide gels show that the external proteins of hamster fibroblast cell lines, which have been identified by lactoperoxidase-catalyzed iodination, do not contain sulphated mucopolysaccharides or hyaluronic acid and are probably unrelated to collagen. Several of the iodinated species comigrate with carbohydrate-containing molecules. In particular, the major iodine-labeled polypeptide of normal fibroblasts appears to be a glycoprotein. This glycoprotein is absent or much reduced in virus-transformed cells, as detected both by iodination and by metabolic labeling. We conclude that the major iodinated polypeptide is not detected on transformed cells because it is absent rather than because it is masked. Approximate molecular weights of the external proteins are also reported.

Improved purification and further characterization of Clostridium perfringens type A enterotoxin

1973 ◽  
Vol 19 (11) ◽  
pp. 1379-1382 ◽  
Author(s):  
A. H. W. Hauschild ◽  
R. Hilsheimer ◽  
W. G. Martin
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Clostridium Perfringens ◽  
Amino Acid Analysis ◽  
Sedimentation Coefficient ◽  
Type A ◽  
Sedimentation Equilibrium ◽  
Molecular Weights ◽  
Hydrolysis Of

The procedure for the purification of Clostridium perfringens type A enterotoxin was simplified, and the purity of the toxin was improved. Hydrolysis of the toxin by the p-toluenesulfonic acid procedure yielded 18 common amino acids. Among these, aspartic acid, serine, leucine, and glutamic acid were the predominant components. The sedimentation coefficient (s°20, w) was 2.8 Svedberg units. The molecular weights determined by the Archibald technique, sedimentation equilibrium, and amino acid analysis were 40 000, 36 000, and 33 000, respectively.

Molecular characterizations of three distinctBabesia gibsonirhoptry-associated protein-1s (RAP-1s)

Parasitology ◽  
2009 ◽  
Vol 136 (10) ◽  
pp. 1147-1160 ◽  
Author(s):  
M. A. TERKAWI ◽  
A. AMORNTHEP ◽  
H. OOKA ◽  
G. ABOGE ◽  
H. JIA ◽  
...  
Keyword(s):  
Recombinant Proteins ◽  
Membrane Fraction ◽  
Babesia Gibsoni ◽  
Est Database ◽  
Serological Screening ◽  
Molecular Weights ◽  
New Genes ◽  
The Matrix ◽  
Molecular Sizes ◽  
Apical Localization

SUMMARYThree cDNAs encoding rhoptry-associated protein 1 (RAP-1) homologues were found in theBabesia gibsoniEST database. Based on similarities to BgRAP-1a, which was identified previously by serological screening of a cDNA merozoite library, the two new genes were designatedBgRAP-1b(33·7%) andBgRAP-1c(57%). Mice antiserum raised against each recombinant protein reacted specifically withB. gibsoniparasites as determined by Western blotting, which showed native molecular sizes of the BgRAP-1a (51 kDa), BgRAP-1b (53 kDa) and BgRAP-1c (47 kDa) consistent with predictable molecular weights. Immunofluoresence using these antibodies revealed localization of all BgRAP-1s within the matrix of merozoites; however, BgRAP-1a appeared to diverge from the other two when it was found secreted into the cytoplasm of infected erythrocytes. Apical localization of all 3 BgRAP-1s during the extracellular stage of the parasite combined with their ability to bind a canine erythrocyte membrane fraction was suggestive of a role for these proteins in erythrocyte attachment. Lastly, the ability of these recombinant proteins to be used as diagnostic reagents was tested by ELISA and the sensitivities of BgRAP-1a and BgRAP-1c were found increased through N-terminal truncation. Taken together, our data suggest divergent roles for the 3 BgRAP-1s in the merozoite stage ofB. gibsoni.

scholarly journals Formation and Characterization of Lactoferrin-Hyaluronic Acid Conjugates and Their Effects on the Storage Stability of Sesamol Emulsions

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3291 ◽  
Author(s):  
Runhua Liu ◽  
Jinhong Zhang ◽  
Caicai Zhao ◽  
Xiang Duan ◽  
David McClements ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Molar Ratio ◽  
Optimum Stability ◽  
Sds Page ◽  
Amine Groups ◽  
Physical And Chemical ◽  
Covalent Conjugates

The purpose of this study was to fabricate biopolymer conjugates from lactoferrin (LF) and hyaluronic acid (HA) and then to investigate their potential as emulsifiers for forming sesamol-loaded emulsions. Initially, LF-HA covalent conjugates were formed using the carbodiimide coupling method in aqueous solutions at pH = 4.5, and then the nature of the conjugates was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy, and fluorescence spectroscopy. The results demonstrated the formation of an amide link between the amine groups of LF and the carboxyl groups of HA. Sesamol emulsions were prepared using the LF-HA conjugates as emulsifiers and their stability was determined. The conjugates improved both the physical and chemical stability of the emulsions during storage. Optimum stability of the emulsion was obtained at a LF-to-HA molar ratio of 2:1. Our results suggest that LF-HA conjugates may be effective emulsifiers for use in food stuffs and other applications.

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