Effect of Hydrogen Peroxide on the Extraction of Components of Cedar Powder with Tetrabutylphosphonium Hydroxide Aqueous Solution at 60°C

2017 ◽  
Vol 70 (3) ◽  
pp. 322 ◽  
Author(s):  
Sachiko Yamanaka ◽  
Koichi Yoshioka ◽  
Hisashi Miyafuji ◽  
Hiroyuki Ohno
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Molecular Weight ◽  
Woody Biomass ◽  
Low Molecular Weight ◽  
Hydroxymethyl Furfural ◽  
Mild Conditions ◽  
Initial Stage ◽  
Aqueous Mixture ◽  
Molecular Weight Fractions

We successfully dissolved cedar powder with tetrabutylphosphonium hydroxide ([P4 4 4 4]OH) aqueous solution at 60°C. The dissolution was accelerated by the addition of H2O2. At the initial stage, cellulose was more soluble than hemicellulose and lignin. Both hemicellulose and lignin were gradually dissolved in this solution containing H2O2. Cellulose chains were revealed to be cut into shorter chains in this solution. The lignin network was also found to be partly broken at 60°C. These steps induced components with higher-molecular-weight fractions that cannot be extracted with polar ionic liquids to dissolve. Also, low-molecular-weight fractions such as vanillin and 5-(hydroxymethyl)furfural were found in the resulting solution. Breakage of ether bonds of polysaccharides and lignin and further oxidation were attributed to the active oxygens generated from H2O2. The aqueous mixture reported here is a protocol that can be used to dissolve woody biomass under mild conditions.

Applications of Algal Polysaccharides and Derivatives in Therapeutic and Agricultural Fields

2019 ◽  
Vol 25 (11) ◽  
pp. 1187-1199 ◽  
Author(s):  
Soukaina Bouissil ◽  
Guillaume Pierre ◽  
Zainab El Alaoui-Talibi ◽  
Philippe Michaud ◽  
C. El Modafar ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Wound Dressing ◽  
Chemical Processes ◽  
Bioactive Molecules ◽  
Present Review ◽  
Agricultural Fields ◽  
Low Molecular Weight ◽  
Molecular Weight Fractions ◽  
Algal Polysaccharides ◽  
Agricultural Fertilizer

Background: Recently, researchers have given more and more consideration to natural polysaccharides thanks to their huge properties such as stability, biodegradability and biocompatibility for food and therapeutics applications. Methods: a number of enzymatic and chemical processes were performed to generate bioactive molecules, such as low molecular weight fractions and oligosaccharides derivatives from algal polysaccharides. Results: These considerable characteristics allow algal polysaccharides and their derivatives such as low molecular weight polymers and oligosaccharides structures to have great potential to be used in lots of domains, such as pharmaceutics and agriculture etc. Conclusion: The present review describes the mains polysaccharides structures from Algae and focuses on the currents agricultural (fertilizer, bio-elicitor, stimulators, signaling molecules and activators) and pharmaceutical (wound dressing, tissues engineering and drugs delivery) applications by using polysaccharides and/or their oligosaccharides derivatives obtained by chemical, physical and enzymatic processes.

Characterization of Elution Chromatography Fractions from CIS-Polybutadiene by GPC

1970 ◽  
Vol 43 (6) ◽  
pp. 1439-1450 ◽  
Author(s):  
W. V. Smith ◽  
S. Thiruvengada
Keyword(s):  
Molecular Weight ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Low Molecular Weight ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
Log Normal ◽  
Analytical Fractionation ◽  
Molecular Weight Fractions ◽  
Elution Chromatography

Abstract A preparative fractionation of about 23 g of a commercial cis-polybutadiene rubber is described. The method employed was a solvent elution chromatographic method with very little temperature gradient. The molecular weight distributions of the fractions obtained were determined by an analytical fractionation of 20 mg of polymer. The method was similar to the preparative fractionation and involved solvent elution chromatography. The fractions obtained were assayed for quantity, molecular weight, and molecular weight distribution by GPC. The low molecular weight fractions of the preparative fractionation had molecular weight distributions which could be closely approximated by two log normal distributions, the low molecular weight component having the narrower width. The ratio of weight to number average molecular weight was found to be about 1.1 for these samples. The higher molecular weight fractions could also be approximated by two log normal distributions; however, in these fractions the low molecular weight component had a very broad distribution but constituted only a small portion of the sample. The widths of the GPC curves of the fractions correlate satisfactorily with the molecular weight distributions found by the analytical refractionations. The GPC width is a sensitive criterion of the width of the molecular weight distribution even when only two columns are used. It is felt that the analytical fractionation procedure presented gives more detailed information on the molecular weight distribution than is easily obtainable from an ordinary GPC curve.

Hepatic Metallothionein in Rainbow Trout (Salmo gairdneri) as an Indicator of Metal Pollution in the Campbell River System

1982 ◽  
Vol 39 (12) ◽  
pp. 1596-1601 ◽  
Author(s):  
M. Roch ◽  
J. A. McCarter ◽  
A. T. Matheson ◽  
M. J. R. Clark ◽  
R. W. Olafson
Keyword(s):  
Molecular Weight ◽  
Rainbow Trout ◽  
Metal Pollution ◽  
Quantitative Measure ◽  
Salmo Gairdneri ◽  
Differential Pulse Polarography ◽  
Low Molecular Weight ◽  
Gel Chromatography ◽  
Hepatic Metallothionein ◽  
Molecular Weight Fractions

Hepatic metallothionein was measured in livers of freshly killed rainbow trout (Salmo gairdneri) using differential pulse polarography. The fish were caught in metal-contaminated lakes of the Campbell River watershed and in a nearby control lake. The livers were analyzed for zinc, copper, and cadmium using atomic absorption spectrophotometry. High and low molecular weight protein fractions were separated by gel chromatography from liver cytosols and analyzed for metals. A downward trend from the most contaminated lake to the least was found in levels of zinc in the water, of cadmium and copper in high molecular weight fractions, and of copper in low molecular weight fractions and metallothionein. The concentration of metallothionein is a useful quantitative measure of the degree of exposure of fish to heavy metals.Key words: metallothionein, rainbow trout, Salmo gairdneri; heavy metal pollution, sublethal exposures, mine wastes

Postsynaptic block of a glutamatergic synapse by low molecular weight fractions of spider venom

1985 ◽  
Vol 339 (2) ◽  
pp. 237-244 ◽  
Author(s):  
A. Bateman ◽  
P. Boden ◽  
A. Dell ◽  
I.R. Duce ◽  
D.L.J. Quicke ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Spider Venom ◽  
Low Molecular Weight ◽  
Glutamatergic Synapse ◽  
Molecular Weight Fractions

scholarly journals Low-molecular weight fractions of Japanese soy sauce act as a RAGE antagonist via inhibition of RAGE trafficking to lipid rafts

2013 ◽  
Vol 4 (12) ◽  
pp. 1835 ◽  
Author(s):  
Seiichi Munesue ◽  
Yasuhiko Yamamoto ◽  
Ryouta Urushihara ◽  
Kouhei Inomata ◽  
Hidehito Saito ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Lipid Rafts ◽  
Soy Sauce ◽  
Low Molecular Weight ◽  
Molecular Weight Fractions

scholarly journals Low Molecular Weight Gelators Based on Functionalized l-Dopa Promote Organogels Formation

Gels ◽  
2019 ◽  
Vol 5 (2) ◽  
pp. 27 ◽  
Author(s):  
Demetra Giuri ◽  
Nicola Zanna ◽  
Claudia Tomasini
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Rheological Properties ◽  
Rhodamine B ◽  
Lauric Acid ◽  
Water Solution ◽  
Preliminary Test ◽  
Low Molecular Weight ◽  
Coupling Reactions ◽  
Low Molecular Weight Gelators

We prepared the small pseudopeptide Lau-l-Dopa(OBn)2-d-Oxd-OBn (Lau = lauric acid; l-Dopa = l-3,4-dihydroxyphenylalanine; d-Oxd = (4R,5S)-4-methyl-5-carboxyl-oxazolidin-2-one; Bn = benzyl) through a number of coupling reactions between lauric acid, protected l-Dopa and d-Oxd with an excellent overall yield. The ability of the product to form supramolecular organogels has been tested with different organic solvents of increasing polarity and compared with the results obtained with the small pseudopeptide Fmoc-l-Dopa(OBn)2-d-Oxd-OBn. The mechanical and rheological properties of the organogels demonstrated solvent-dependent properties, with a storage modulus of 82 kPa for the ethanol organogel. Finally, to have a preliminary test of the organogels’ ability to adsorb pollutants, we treated a sample of the ethanol organogel with an aqueous solution of Rhodamine B (RhB) for 24 h. The water solution slowly lost its pink color, which became trapped in the organogel.

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