scholarly journals Fucoidan Characterization: Determination of Purity and Physicochemical and Chemical Properties

Marine Drugs ◽  
2020 ◽  
Vol 18 (11) ◽  
pp. 571
Author(s):  
Ahmed Zayed ◽  
Mona El-Aasr ◽  
Abdel-Rahim S. Ibrahim ◽  
Roland Ulber
Keyword(s):  
Structural Characteristics ◽  
Chemical Properties ◽  
Industrial Applications ◽  
Chemical Structures ◽  
Seasonal Factors ◽  
Molecular Masses ◽  
Current Article ◽  
Downstream Processes

Fucoidans are marine sulfated biopolysaccharides that have heterogenous and complicated chemical structures. Various sugar monomers, glycosidic linkages, molecular masses, branching sites, and sulfate ester pattern and content are involved within their backbones. Additionally, sources, downstream processes, and geographical and seasonal factors show potential effects on fucoidan structural characteristics. These characteristics are documented to be highly related to fucoidan potential activities. Therefore, numerous chemical qualitative and quantitative determinations and structural elucidation methods are conducted to characterize fucoidans regarding their physicochemical and chemical features. Characterization of fucoidan polymers is considered a bottleneck for further biological and industrial applications. Consequently, the obtained results may be related to different activities, which could be improved afterward by further functional modifications. The current article highlights the different spectrometric and nonspectrometric methods applied for the characterization of native fucoidans, including degree of purity, sugar monomeric composition, sulfation pattern and content, molecular mass, and glycosidic linkages.

Topological characterization of dendrimer, benzenoid, and nanocone

2018 ◽  
Vol 74 (1-2) ◽  
pp. 35-43
Author(s):  
Wei Gao ◽  
Muhammad Kamran Siddiqui ◽  
Najma Abdul Rehman ◽  
Mehwish Hussain Muhammad
Keyword(s):  
Chemical Properties ◽  
Chemical Compounds ◽  
Topological Indices ◽  
Zagreb Index ◽  
Topological Characterization ◽  
Complex Molecules ◽  
Chemical Structures ◽  
Physico Chemical ◽  
Quantitative Structure Activity Relationships

Abstract Dendrimers are large and complex molecules with very well defined chemical structures. More importantly, dendrimers are highly branched organic macromolecules with successive layers or generations of branch units surrounding a central core. Topological indices are numbers associated with molecular graphs for the purpose of allowing quantitative structure-activity relationships. These topological indices correlate certain physico-chemical properties such as the boiling point, stability, strain energy, and others, of chemical compounds. In this article, we determine hyper-Zagreb index, first multiple Zagreb index, second multiple Zagreb index, and Zagreb polynomials for hetrofunctional dendrimers, triangular benzenoids, and nanocones.

scholarly journals Antioxidant Activity and Characterization of One New Polysaccharide Obtained fromPerigord Truffle(Tuber huidongense)

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Yong-Feng Chen ◽  
Wen-wen Jiang ◽  
Shi-qi Zhang ◽  
Jian-quan Kan ◽  
Yong Liang
Keyword(s):  
Molecular Structure ◽  
Antioxidant Activity ◽  
Structural Characteristics ◽  
Water Soluble ◽  
Separation And Purification ◽  
Edible Fungus ◽  
Main Components ◽  
First Time

As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) fromPerigord Truffle(Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6)α-D-Glcp(1→6)  α-D-Glcp (1→]nby methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50of 2.81, 4.17, and 3.44 mg/mL, respectively. However,O2-∙clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree.

Characterization of a humic gel synthesized from an activated epoxy silica gel

2002 ◽  
Vol 90 (4) ◽  
Author(s):  
C. Barbot ◽  
K. Czerwinski ◽  
Gunnar Buckau ◽  
J. I. Kim ◽  
Valérie Moulin ◽  
...  
Keyword(s):  
Humic Acid ◽  
Silica Gel ◽  
Chemical Properties ◽  
Column Experiments ◽  
Surface Binding ◽  
Silica Gel Particles ◽  
And Chemical Properties ◽  
Covalently Bound

SummaryPurified humic acid has been covalently bound on activated epoxy silica gel particles. Determination of physical properties and chemical properties was conducted in order to characterize the material at different stages of the preparation. FTIR spectra and the PEC of the surface bound humic acid is very similar to that of humic acid starting material. This shows that the humic acid was not deteriorated during the surface binding process. This humic gel can be used as an analogue for sediment associated humic acid, with the advantage that covalently bound humic acid does not desorb, and thus allows for simple species separation between non-complexed and humic bound metal ions in batch and column experiments.

scholarly journals Combined XRD and EXAFS characterization of UiO-66 and functionalized UiO-67 MOFs

2014 ◽  
Vol 70 (a1) ◽  
pp. C593-C593
Author(s):  
Elisa Borfecchia ◽  
Sigurd Øyen ◽  
Kirill Lomachenko ◽  
Boris Bouchevreau ◽  
Elisa Chiari ◽  
...  
Keyword(s):  
High Pressures ◽  
Industrial Applications ◽  
Catalytic Reactions ◽  
Gas Purification ◽  
Exafs Data ◽  
Industrial Impact ◽  
Acids And Bases ◽  
Waste Scavenging

The recently discovered UiO-66 (UiO-67) class of isostructural metallorganic frameworks (MOFs) are obtained connecting Zr6O4(OH)4 inorganic cornerstones with 1,4-benzene-dicarboxylate (4,4′ biphenyl-dicarboxylate) as linker resulting in a cubic framework [1]. This family of MOFs has attracted great interest because of its remarkable stability at high temperatures, high pressures and in presence of different solvents, acids and bases [2]. Industrial applications in the fields of catalysis, H2 storage, gas purification and, for the isostructural Hf form, interim radioactive waste scavenging. For these potentialities UiO-66 is one of the very few MOFs that have already been successfully commercialized. In this presentation we will show how the synergic refinement of XRPD and EXAFS data resulted in the structural determination of UiO-66/67 [1-3] and we will report new combined synchrotron radiation single crystal XRD and EXAFS data allowing the structure determination of new metal-functionalized UiO-67 of potential high industrial impact because aimed in heterogenization of homogeneous catalytic reactions.

scholarly journals Isolation and Characterization of Phages InfectingBacillus subtilis

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Anna Krasowska ◽  
Anna Biegalska ◽  
Daria Augustyniak ◽  
Marcin Łoś ◽  
Malwina Richert ◽  
...  
Keyword(s):  
Food Production ◽  
Burst Size ◽  
Industrial Applications ◽  
Isolation And Characterization ◽  
Latent Time ◽  
Food Borne ◽  
Alternative Approach ◽  
Sds Page

Bacteriophages have been suggested as an alternative approach to reduce the amount of pathogens in various applications. Bacteriophages of various specificity and virulence were isolated as a means of controlling food-borne pathogens. We studied the interaction of bacteriophages withBacillusspecies, which are very often persistent in industrial applications such as food production due to their antibiotic resistance and spore formation. A comparative study using electron microscopy, PFGE, and SDS-PAGE as well as determination of host range, pH and temperature resistance, adsorption rate, latent time, and phage burst size was performed on three phages of theMyoviridaefamily and one phage of theSiphoviridaefamily which infectedBacillus subtilisstrains. The phages are morphologically different and characterized by icosahedral heads and contractile (SIOΦ, SUBω, and SPOσphages) or noncontractile (ARπphage) tails. The genomes of SIOΦ and SUBωare composed of 154 kb. The capsid of SIOΦ is composed of four proteins. Bacteriophages SPOσand ARπhave genome sizes of 25 kbp and 40 kbp, respectively. Both phages as well as SUBωphage have 14 proteins in their capsids. Phages SIOΦ and SPOσare resistant to high temperatures and to the acid (4.0) and alkaline (9.0 and 10.0) pH.

scholarly journals Molecular Characterization of Novel Family IV and VIII Esterases from a Compost Metagenomic Library

2021 ◽  
Vol 9 (8) ◽  
pp. 1614
Author(s):  
Jong-Eun Park ◽  
Geum-Seok Jeong ◽  
Hyun-Woo Lee ◽  
Hoon Kim
Keyword(s):  
Metagenomic Library ◽  
Industrial Applications ◽  
Native Form ◽  
Metagenome Library ◽  
The Family ◽  
Alkaline Conditions ◽  
Molecular Masses ◽  
Novel Esterase ◽  
Family Iv

Two novel esterase genes, est8L and est13L, were isolated and identified from a compost metagenomic library. The encoded Est8L and Est13L had molecular masses of 33,181 and 44,913 Da consisting of 314 and 411 amino acids, respectively, without signal peptides. Est8L showed the highest identity (32.9%) to a hyper-thermophilic carboxylesterase AFEST from Archaeoglobus fulgidus compared to other esterases reported and was classified to be a novel member of family IV esterases with conserved regions such as HGGG, DY, GXSXG, DPL, and GXIH. Est13L showed the highest identity (98.5%) to the family VIII esterase Est7K from the metagenome library. Est8L and Est13L had the highest activities for p-nitrophenyl butyrate (C4) and p-nitrophenyl caproate (C6), respectively, and Est13L showed a broad substrate specificity for p-nitrophenyl substrates. Est8L and Est13L effectively hydrolyzed glyceryl tributyrate. The optimum temperatures for activities of Est8L and Est13L were identical (40 °C), and the optimum pH values were 9.0 and 10.0, respectively. Est13L showed higher thermostability than Est8L. Sephacryl S-200 HR chromatography showed that the native form of Est8L was a dimer. Interestingly, Est13L was found to be a tetramer, contrary to other family VIII esterases reported. Est8L was inhibited by 30% isopropanol, methanol, and acetonitrile; however, Est13L was activated to 182.9% and 356.1%, respectively, by 30% isopropanol and methanol. Est8L showed enantioselectivity for the S-form, but Est13L showed no enantioselectivity. These results show that intracellular Est8L and/or Est13L are oligomeric in terms of native forms and can be used for pharmaceutical and industrial applications with organic solvents under alkaline conditions.

scholarly journals INTERCALATION OF OLYGOMER OF HYDROXYL-CHROMIUM INTO NATURAL KAOLINITE

2010 ◽  
Vol 8 (1) ◽  
pp. 31-36
Author(s):  
Rodiansono Rodiansono ◽  
Reda Ariyantie ◽  
Abdullah Abdullah
Keyword(s):  
Surface Area ◽  
Pore Radius ◽  
Nitrate Solution ◽  
Chemical Properties ◽  
Basal Spacing ◽  
Physico Chemical ◽  
Ft Ir ◽  
N2 Sorption

Preparation of a kaolin-hydroxyl chromium composite and characterization of its physico-chemical properties were conducted. The olygomer hydroxyl-chromium was prepared by adding Na2CO3 to 0.1 M chromium nitrate solution (ratio OH/Cr = 2) and then dried at 110 oC and 400 oC for 4 h. Characterization of kaolin-hydroxyl chromium composite includes determination of acidity, functional groups, basal spacing, and surface area (BET-N2 sorption analyzer). The result showed that intercalation of hydroxyl chromium resulted in the decreasing of basal spacing but increased the specific surface area of kaolin. Drying of the intercalated kaolin at 400 oC decreased surface area, total volume pore and pore radius. FT-IR spectra showed that hydroxyl-chromium detected at wavelength of 2925 and 2855 cm-1.   Keywords: natural kaolin, intercalation, olygomer hydroxyl-chromium, kaolin-hydroxyl chromium composite

scholarly journals Rat thimet oligopeptidase: large-scale expression in Escherichia coli and characterization of the recombinant enzyme

1995 ◽  
Vol 309 (1) ◽  
pp. 203-207 ◽  
Author(s):  
N McKie ◽  
P M Dando ◽  
M A Brown ◽  
A J Barrett
Keyword(s):  
Escherichia Coli ◽  
Large Scale ◽  
Chemical Properties ◽  
Zinc Content ◽  
Recombinant Enzyme ◽  
Naturally Occurring ◽  
Thimet Oligopeptidase ◽  
Thiol Content

The coding sequence for rat testis thimet oligopeptidase (TOP) (EC 3.4.24.15) was placed under the control of the T7 polymerase/promoter system. Cultures of Escherichia coli transfected with the resulting plasmid expressed the enzyme as a soluble cytoplasmic protein. Medium-scale cultures allowed isolation of the enzyme in quantities of tens of milligrams. The availability of the recombinant enzyme permitted the determination of such chemical properties as epsilon 280 (48,960), zinc content (2 atom/molecule) and available thiol content (8-10/molecule) for TOP. The recombinant enzyme showed the catalytic activities previously reported for the naturally occurring enzyme, so that we can now conclude with confidence that these are all due to TOP and there is no need to postulate the existence of separate ‘Pz-peptidase’ or ‘endo-oligopeptidase A’ enzymes.

Synthesis and Characterization of Tin Oxide Nanoparticles Heavily Doped with Antimony

1997 ◽  
Vol 3 (S2) ◽  
pp. 433-434
Author(s):  
J. Liu ◽  
J. P. Coleman ◽  
P. Madhukar
Keyword(s):  
Tin Oxide ◽  
Chemical Properties ◽  
Structural Evolution ◽  
Industrial Applications ◽  
Carbon Films ◽  
Electrochromic Devices ◽  
Transmission Electron ◽  
Heavily Doped ◽  
Tin Oxide Nanoparticles

Antimony-doped tin oxide (ATO) materials have many interesting and useful properties for industrial applications. Important uses of ATO include anti-static pigments, catalysts, electrochromic devices, solar cells, gas sensors, etc. Although the electro-optical and the structural properties of ATO materials with low dopant levels have been extensively investigated,the fundamental structural/chemical properties of heavily doped ATO materials have not been well understood. We report here some preliminary results of a systematic study of the structural evolution of tin oxide nanopaiticles heavily doped with antimony.The ATO powders were prepared by adding a mixture of antimony(V) chloride and tin(IV) chloride to deionised water with concurrent addition of sodium hydroxide. The resulting white precipitates were filtered, washed and dried at room temperature. A series of Sb-doped SnO2 samples was obtained by annealing the precipitates at various temperatures. Samples suitable for high resolution transmission electron microscopy (HRTEM) were prepared by dry-dispersing ATO powders onto holey carbon films.

Influence of Application Technology in the Structural Characteristics of Ceramic Coatings with Advanced Anticorrosive and Tribological Properties

2014 ◽  
Vol 91 ◽  
pp. 108-116 ◽  
Author(s):  
David Vélez ◽  
Josemari Muñoz ◽  
José Antonio Diez
Keyword(s):  
Ceramic Coating ◽  
Structural Characteristics ◽  
Ceramic Coatings ◽  
Industrial Applications ◽  
Application Technology ◽  
Precise Control ◽  
Surface Finishes ◽  
Coating Method ◽  
Microstructure Morphology

Electrophoretic deposition (EPD) of ceramic frits is shown to be a useful coating method for different metal surfaces and geometries since it allows obtaining very smooth surface finishes with precise control of their thickness. By the other hand, these kind of coatings show differences with the coatings obtained by conventional wet application methods as dipping, flow-coating, slushing and spraying. At this point, CIDETEC has used an own advanced ceramic coating based on no commercial enamels to determinate the best application method to obtain an excellent anticorrosive coating on carbon steel. In view of possible scaling up to particular industrial applications, a detailed characterization of the microstructure, morphology, physical, chemical and mechanical properties of the coatings was performed. The preliminary studies show that EPD system improves the characteristics of this coating.

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