Comparison of Polysaccharides Extracted from Cultivated Mycelium of Inonotus obliquus with Polysaccharide Fractions Obtained from Sterile Conk (Chaga) and Birch Heart Rot

The polysaccharides of the sterile conk of Inonotus obliquus (Chaga) have demonstrated multiple bioactivities. The mycelium of this basidiomycete, obtained after submerged cultivation, has been considered a feasible alternative to the sterile conk for the production of polysaccharides. However, previous research has paid little attention to the differences in the structures of polymers obtained from the different resources. Moreover, the birch wood colonized by I. obliquus has never been investigated as a source of bioactive polysaccharides. In the present study, polysaccharide fractions produced from cultivated mycelium, sterile conks of different geographical origins, and birch heart rot were investigated. High amounts of phenolic compounds, possibly lignans, were bound to the sterile conk polysaccharides. Mycelial polysaccharides were rich in α- and β-glucans and had high (105 Da) and low (104 Da) molecular weight populations. On the other hand, sterile conk polysaccharides were mainly β-glucan of lower and monodispersed molecular weight (103 Da). Heart rot polysaccharides were comprised mainly of low molecular weight (103 Da) hemicelluloses. Nevertheless, fungal polysaccharides were identified in the extracts. The differences in structure and molecular properties among the polysaccharide fractions of mycelium, heart rot, and sterile conk are likely associated with differences in bioactivities and, therefore, in nutraceutical potential.

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Lignin Valorization: Concentration of Model Phenolic Compounds by Nanofiltration

U Porto Journal of Engineering ◽

10.24840/2183-6493_003.001_0007 ◽

2018 ◽

Vol 3 (1) ◽

pp. 72-78

Author(s):

Elson Dinis Gomes ◽

P. C. R. Pinto ◽

Alírio E. Rodrigues

Keyword(s):

Molecular Weight ◽

Phenolic Compounds ◽

Phenolic Compound ◽

Value Added ◽

Model Solution ◽

The Other ◽

Low Molecular Weight ◽

Nanofiltration Membranes ◽

Lignin Valorization ◽

Lignin Oxidation

Lignin is a biopolymer found in plants which can be valorized as a source of value added compounds by breaking its structure in the constituting monomers. A model solution was prepared with seven phenolic compounds, including vanillin and syringaldehyde, usually found after alkaline lignin oxidation. The model solution was concentrated by nanofiltration membranes with low molecular weight cut-off (MWCO). Two membranes (DOW NF270 and KOCH MPS-34) were tested for permeate fluxes and phenolic compound rejection. Significant reduction of the volume mixture was achieved with high permeate fluxes as well as high rejections (above 90%) for the phenolic compounds studied. The membrane with the best performance was the DOW NF270 with maintained high rejections while having higher permeate fluxes resulting in higher productivity when compared with the other membrane KOCH MPS-34 also tested.

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Bridge-therapy with enoxaparin in the preoperative period of endarterectomy

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x2010000500019 ◽

2010 ◽

Vol 68 (5) ◽

pp. 775-777

Author(s):

Jair Leopoldo Raso ◽

Rogério Zenóbio Darwich ◽

Francisco de Lucca Jr ◽

Romeu Valle Santana ◽

Marco Túlio Tanure ◽

...

Keyword(s):

Molecular Weight ◽

Mortality Rate ◽

Prospective Study ◽

Low Molecular Weight Heparin ◽

The Other ◽

Low Molecular Weight ◽

Preoperative Period ◽

Safe Strategy ◽

A Prospective Study ◽

Bridge Therapy

Cervical clot is one of the complications of endarterectomy. This risk may be higher in patients using aspirin or clopidogrel. On the other hand, stroke may occur if the medication is interrupted before surgery. We carried out a prospective study of 124 endarterectomies in 119 patients in which aspirin or clopidogrel was stopped and a bridge-therapy with enoxaparin was administered preoperatively. There was no case of stroke during the period of the bridge-therapy. One patient developed cervical clot (0.8%) in the fifth postoperative day. Mortality rate in this series was 0.8%. There was no complication directly related to the use of enoxaparin. Bridge-therapy with low molecular weight heparin is a safe strategy for patients elected for endarterectomy

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In Vitro Characterization Of Low Molecular Weight Fractions Of Heparin

10.1055/s-0038-1653144 ◽

1981 ◽

Author(s):

Jawed Fareed ◽

Harry L Messmore ◽

Daniel A Walz ◽

Jean Choay ◽

J C Lormeau

Keyword(s):

Molecular Weight ◽

The Other ◽

Low Molecular Weight ◽

In Vitro Test ◽

Thrombin Time ◽

Specific Test ◽

Platelet Factor ◽

At Iii ◽

Heparin Fractions

Numerous extraction, chromatographic (ion exchange, gel, and affinity), chemical and enzymatic degradation methods have been employed to obtain heparin fractions. The present assays to evaluate potency (e.g. pharmacopeial and coagulant) do not truly reflect the antithrombotic properties of these fractions. In addition, the synthetic peptide substrate based assays to measure the anti Xa activity do not correlate with the coagulant anti Xa assays. We have developed an in vitro test battery to evaluate low molecular weight heparin fractions. Porcine mucosal heparin fractions are assayed for anti Xa activity in coagulant and amidolytic assays and the results are expressed as a ratio. The effect of these fractions on coagulant assays such as prothrombin time (PT), partial thromboplastin time (PTT), thrombin time (TT), Stypven time (ST) on freshly prepared normal human plasma (NHP) is determined The retention characteristics of these fractions on platelet factor 4 and AT-III bound sepharose columns were also determined. We have compared the extracted and chemically depolymerized heparin fractions and found that the anti Xa activity doesn’t always correlate with the other parameters studied. The extracted fractions were slightly stronger in the USP assays and showed a biphasic retention on the PF-4 column whereas the chemically depolymerized product showed only one peak. On the other hand, on the AT-III column both fractions showed similar elution patterns. Our studies suggest that heparin and its fractions exhibit differential behavior on various assays and a specific test may not be used as an index of the potency of their antithrombotic effects. Furthermore, the potency of these fractions should be stated on a weight basis when evaluated in the in vivo animal models rather than in terms of a specific test (e.g. anti Xa activity and US Pharmacopeial assays).

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STUDIES ON THE ISOLATION AND NATURE OF THE 'TERREGENS FACTOR'

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y54-043 ◽

1954 ◽

Vol 32 (1) ◽

pp. 400-406 ◽

Cited By ~ 10

Author(s):

M. O. Burton ◽

F. J. Sowden ◽

A. G. Lochhead

Keyword(s):

Amino Acids ◽

Molecular Weight ◽

Ferric Iron ◽

Test Organism ◽

The Other ◽

Inorganic Salts ◽

Low Molecular Weight ◽

Straight Chain ◽

Heat Stable ◽

Growth Promoting

A procedure is described for the production and concentration of the 'terregens factor' (TF), a bacterial growth promoting substance synthesized by Arthrobacter pascens and essential for the growth of Arthrobacter terregens. From culture filtrates of A. pascens cultivated in a medium of inorganic salts and sucrose, concentrates of TF may be obtained that are active at 0.001 μgm. Per ml., heat stable and contain about 12.7% nitrogen. Acid hydrolysis yielded a number of amino acids, including glutamic acid, glycine, α–alanine, valine, leucine, proline, lysine, and arginine, as well as some unidentified compounds; however, TF does not appear to be a low molecular weight straight chain peptide.Although TF contains no iron, it combines readily with ferrous or ferric iron to form reddish-brown complexes with this metal. Activity for A. terregens is shown by certain iron containing complexes as hemin, coprogen, and ferrichrome. On the other hand none is shown by cytochrome or pulcherrimin; however, aspergillic acid, structurally related to the latter, possesses some growth promoting activity for the test organism.

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Impact of malolactic fermentation on low molecular weight phenolic compounds

Talanta ◽

10.1016/j.talanta.2007.08.045 ◽

2008 ◽

Vol 74 (5) ◽

pp. 1281-1286 ◽

Cited By ~ 32

Author(s):

M.J. Cabrita ◽

M. Torres ◽

V. Palma ◽

E. Alves ◽

R. Patão ◽

...

Keyword(s):

Molecular Weight ◽

Phenolic Compounds ◽

Malolactic Fermentation ◽

Low Molecular Weight

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Viscoelastic Properties of Unentangled Multicyclic Polystyrenes

Polymers ◽

10.3390/polym10090973 ◽

2018 ◽

Vol 10 (9) ◽

pp. 973 ◽

Cited By ~ 1

Author(s):

Zhi-Chao Yan ◽

Md. Hossain ◽

Michael Monteiro ◽

Dimitris Vlassopoulos

Keyword(s):

Molecular Weight ◽

Shear Viscosity ◽

Viscoelastic Properties ◽

Dilution Effect ◽

The Other ◽

Low Molecular Weight ◽

Zero Shear Viscosity ◽

Rouse Model ◽

Loop Size ◽

Linear Chains

We report on the viscoelastic properties of linear, monocyclic, and multicyclic polystyrenes with the same low molecular weight. All polymers investigated were found to exhibit unentangled dynamics. For monocyclic polymers without inner loops, a cyclic-Rouse model complemented by the contribution of unlinked chains (whose fraction was determined experimentally) captured the observed rheological response. On the other hand, multicyclic polymers with inner loops were shown to follow a hierarchical cyclic-Rouse relaxation with the outer loops relaxing first, followed by the inner loop relaxation. The influence of unlinked linear chains was less significant in multicyclic polymers with inner loops. The isofrictional zero-shear viscosity decreased with increasing number of constrained segments on the coupling sites, which was attributed to the decreasing loop size and the dilution effect due to the hierarchical relaxation.

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Fractionation of the Color of Pure Maple and Other Sirups by Gel Filtration

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/48.3.493 ◽

1965 ◽

Vol 48 (3) ◽

pp. 493-497

Author(s):

E E Stinson ◽

C O Willits

Keyword(s):

Molecular Weight ◽

Gel Filtration ◽

Cane Sugar ◽

The Other ◽

Low Molecular Weight ◽

Brown Sugar ◽

Maple Sugar ◽

Molecular Weight Fractions ◽

Color Fraction

Abstract The colorants of pure maple, cane and maple, refined cane sugar, and light brown sugar sirups were separated into two fractions, one of high- and the other of lowmolecular weights, by means of gel filtration. The ratio of the amounts of high- to the low-molecular weight fractions of pure maple was the lowest of the four sirups and serves as a means of differentiation from these sirups. The color fraction ratio was highest for blended cane-maple sugar sirup. Many maple sirups are also distinguished by a pink band formed on the gel filtration column.

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Butyl Networks Containing Unattached Polyisobutylene Chains: Part II, Correlation of Tear, Tensile, and Hysteretic Properties

Rubber Chemistry and Technology ◽

10.5254/1.3538205 ◽

1986 ◽

Vol 59 (2) ◽

pp. 347-360 ◽

Cited By ~ 10

Author(s):

G. R. Hamed ◽

F. Ogbimi

Keyword(s):

Molecular Weight ◽

Crack Tip ◽

The Other ◽

Low Molecular Weight ◽

Load Bearing ◽

Tear Strength ◽

Tearing Energy ◽

High Molecular Weight Polyisobutylene ◽

Hysteretic Properties ◽

Crack Tip Blunting

Abstract Butyl networks containing either unattached polyisobutylene chains or a low-molecular-weight plasticizer have been made by crosslinking butyl rubber in the presence of one of these diluents. With dodecane as a plasticizer, tear strength is reduced both because of a decrease in the density of load-bearing chains and diminished hysteresis. On the other hand, when the diluent is a high-molecular-weight polyisobutylene, tear strength is enhanced if the test rate is sufficiently high. In this case, the polyisobutylene chains are load bearing (at least initially) before slipping at higher strains to relieve local crack-tip stresses and blunt the propagating tear. This hysteretic mechanism delays the onset of crack propagation, thereby enhancing the fracture energy. However, at low tear rates, in which there is adequate time for the unattached chains to relax such that they bear little load and hysteresis is minimized, tear strength decreases with increasing free-chain content—much the same as occurs with a low-molecular-weight diluent. Finally, under conditions in which the average propagating tearing energy is enhanced for the butyl-polyisobutylene system, the initiation tearing energy is increased only moderately. This suggests that crack-tip blunting during steady-state tearing is at least partially responsible for increases in strength in the presence of free chains.

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Influence of Botanical Species and Geographical Origin on the Content of Low Molecular Weight Phenolic Compounds of Woods Used in Portuguese Cooperage

Holzforschung ◽

10.1515/hf.2000.043 ◽

2000 ◽

Vol 54 (3) ◽

pp. 255-261 ◽

Cited By ~ 29

Author(s):

Sara Canas ◽

M. Conceição Leandro ◽

M. Isabel Spranger ◽

A. Pedro Belchior

Keyword(s):

Molecular Weight ◽

Phenolic Compounds ◽

Geographical Origin ◽

Castanea Sativa ◽

Total Content ◽

Low Molecular Weight ◽

Qualitative And Quantitative ◽

Botanical Species ◽

The Difference ◽

Chestnut Wood

Summary The influence of botanical species (Quercus and Castanea sativa) and geographical origin (Portugal—three different sites, France and North America) on the qualitative and quantitative content of some extractable low molecular weight phenolic compounds was assessed by HPLC. Chestnut wood had the highest total content of low molecular weight phenolic compounds, followed by the Portuguese oaks and the French oaks, whereas the American oak had the lowest content of these compounds. The contents of phenolic acids, phenolic aldehydes, scopoletin and umbelliferone were significantly different among the studied woods. Both the botanical species and the geographical origin affect the content of low molecular weight organic compounds of woods used in Portuguese cooperage. The results also show that the botanical species seem to be more important than the geographical origin to explain the difference in the wood phenolic composition. So, the separation of trees according to their origin is of considerable interest for coopers and winemakers to choose wisely the woods for the ageing of brandies.

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