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Chemical characterization and biochemical activity of polysaccharides isolated from Egyptian Ulva fasciata Delile

Moawad Madelyn N., El-Sayed Abeer A.M., Abd El Latif Hala H., El-Naggar Naglaa A., El-Din Nihal G. Shams, Tadros Hermine R.Z.

Oceanologia

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2022

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No. 64 (1)

117--130

EN

This study gives updated information on the isolation of ulvan from green alga Ulva fasciata Delile in Egypt through isolation and chemical characterization of sulfate polysaccharides by two sequential extraction steps using different solvents; distilled water, HCl and Na2EDTA forming fraction I (F-I). Fraction II (F-II) was obtained from remaining seaweeds using NaOH to give FDWNaOH, FHClNaOH, and FEDTANaOH. All products obtained were tested for their biological activities. The highest polysaccharides total extraction yield was 11.8% for water extract (F-I and F-II). The highest protein content was found in FEDTANaOH (2.44%). The highest sulfate content was recorded for F-I (HCl) (21.38%). Total carbohydrates range was 11.99–63.90% for F-I and 15.06–76.65% for F-II. Monosaccharides; galactose, rhamnose, and uronic acid were detected at all fractions, with concentrations varying from 0.11 to 1.34%, from 0.61 to 1.81% and from 11.06 to 19.30%, respectively. 1H NMR of F-II demonstrated the signals of ring and methyl protons of polysaccharide. The appearance of the stretching bands of the sulfate ester (C-O-S) and sulfate groups (S=O) in the FT-IR spectrum of FHClNaOH confirmed the presence of sulfated polysaccharides, typical of ulvan. The microbial species Vibrio damsela was the most susceptible to FDWNaOH, followed by Aeromonas hydrophila and Vibrio fluvialis with inhibition zones of 30, 22, 22 mm at 150 mg/ml, respectively. FDWNaOH was the most effective fraction having antifouling property. The highest antioxidant activity was observed for F-IHCl followed by FDWNaOH. At concentrations 25 and 50 mg/l, FEDTANaOH displayed the highest anti-inflammatory activity (94.0 and 91.40%, respectively).

2

Structural Elucidation Of Transition Metal Complexes of The Schiff base of 5- Nitro Salicylaldehyde And Anthranalic Acid Using&ensp1H NMR, Thermal Analysis, Diffused Reflectance and ESR data

More P. S., Mehta B. H.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 48

1--13

EN

Transition metal complexes of the type ML.nH2O [Where M= Co(II),Ni(II),Cu(II) and Zn(II), L= Schiff base of 5 nitro salicylaldehyde and anthranalic acid , n= 0,1 …..] were characterized by using&ensp1H NMR ,TGA, Diffused refluctance and ESR spectroscopy. On the basis of above studies Co(II), Ni(II) shows tetrahedral structure, Cu(II) shows binuclear structure and Zn(II) shows square planar structure.

3

1H NMR, Diffused Reflectance, Thermal studies, ESR and Anti microbial Activities of Schiff Base Derived from 5- Nitro Salicylaldehyde and p-Anisidine

More P. S., Mehta B. H.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 48

14--26

EN

Transition metal complexes of the type ML1 [Where M= Co(II),Ni(II),Cu(II) and Zn(II), L= Schiff base of 5 nitro-salicylaldehyde and p- anisidine were characterized by using&ensp1H NMR ,TGA, Diffused reflectance and ESR spectroscopy. On the basis of above studies Co(II), Ni(II) shows tetrahedral structure, Cu(II) and Zn(II) shows square planar structure.

4

Wpływ dodatku ekspandowanego grafitu (EG) na przebieg syntezy i charakterystykę poli(tereftalanu etylenu) modyfikowanego 1,4-cykloheksanodimetanolem (PETG)

Paszkiewicz S, Szymczyk A, Špitalský Z, Mosnáček J, Janus E, Rosłaniec Z

Polimery

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2013

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T. 58, nr 11-12

893--899

PL

Zbadano wpływ dodatku nanonapełniacza węglowego (ekspandowanego grafitu) na przebieg syntezy PETG (kopolimeru PET-ran-PCT), morfologię nanokompozytu oraz jego przemiany fazowe. Badany nanokompozyt zawierał 0,1 % mas. ekspandowanego grafitu (EG) w postaci pojedynczych płaszczyzn grafenowych oraz (w większości) luźno złączonych paczek grafenów. Nie stwierdzono wpływu nanocząstek EG na przemiany fizyczne w kopolimerze PET-ran-PCT. Na termogramach układu zawierającego 20 lub 30 % mol. PCT nie zaobserwowano piku topnienia ani krystalizacji. Na podstawie analizy ilościowej produktów ubocznych metodą chromatografii gazowej ustalono, że skład otrzymanego polimeru był zgodny z obliczonym na podstawie stechiometrycznych ilości głównych składników. Budowę chemiczną zsyntezowanego kopolimeru potwierdzono przy użyciu spektroskopii 1H NMR.

EN

In this work, the effect of the addition of carbon nanofiller (expanded graphite) on the process of synthesis of PETG (PET-ran-PCT copolymer), morphology of the resulting nanocomposite and its phase transitions has been studied. The examined PETG contained 0.1 wt. % expanded graphite (EG) in the form of single graphene sheets and (predominantly) loosely assembled graphene bundles, as it was observed by SEM analysis (Fig. 4a). No influence of EG nanoparticles on the physical changes in the PET-ran-PCT copolymer was found. DSC thermograms of PETG with 20 or 30 mol. % PCT content did not show melting or crystallization peaks (Fig. 5). The results of quantitative analysis of by-products using gas chromatography indicated that the composition of the prepared polymer was in accordance with that calculated from the stoichiometric amounts of main components. Additionally, the molecular structure of synthesized copolymers was confirmed by 1H NMR spectroscopy (Fig. 3). The signals in the range 2,41—1,63 ppm (peak d) indicated the presence of cis-trans isomers corresponding to cyclohexanedimethanol in the copolymer.

5

Hydrolysis of silica sources: APS and DTSACl in microencapsulation processes

Szczepanowicz K., Para G., Bouzga A. M., Simon Ch., Yang J., Warszynski P.

Physicochemical Problems of Mineral Processing

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2012

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Vol. 48, iss. 2

403-412

EN

The process of formation of silica shells around emulsion droplets was investigated. The 1H-NMR spectroscopy was applied to follow the silica shell formation around emulsion droplets by hydrolysis and condensation of selected silanes in the emulsion system. (3- aminopropyl) triethoxysilane (APS) and dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride (DTSACl) were used as silica sources in microencapsulation process. The NMR analysis revealed strong dependence of the hydrolysis reaction rate on pH. Obtained information allowed selecting the optimal conditions for the formation of the capsules with silica shells. The obtained capsules' suspensions were stable for several weeks.

6

Wykorzystanie metod spektroskopowych w badaniach procesów i produktów polimeryzacji rodnikowej

Pabin-Szafko B., Wiśniewska E.

Chemik

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2011

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Vol. 65, nr 7

637-642

PL

Zastosowanie metod spektroskopowych w chemii polimerów pozwala na uzyskanie niezbędnych informacji przy identyfikowaniu struktury chemicznej związków i tym samym na badanie różnych procesów, począwszy od syntezy inicjatorów, ich zachowania się w różnych warunkach (np. w reakcji rozpadu), poprzez badanie pozostałych substratów oraz produktów polimeryzacji, a także badanie innych procesów - modyfikacji czy destrukcji polimerów.

EN

The utilization of spectroscopic methods in polymer chemistry allows obtaining the necessary information to identify the chemical structure of compounds and moreover different processes studies, starting from initiator synthesis, their behaviour at various conditions (e.g. during thermal decomposition), through the other polymerization substrates and products study, and also other processes - polymers modification or destruction investigations.

7

Structure Determination of Some Nitro-5,10,15,20-tetrakis(3-methoxyphenyl)porphyrins Using Simple NMR Techniques

Ostrowski S., Łopuszyńska B., Mikus A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 7

1209-1215

EN

The structures of some nitrosubstituted meso-tetraarylporphyrins were determined by a simple comparison of their 1H NMRspectra, and confirmed by NOE experiments. On the basis of these investigations it was found that in the meso-tetraphenylporphyrin (meso-TPP) and its 3-methoxy, 3-methyl, and 3-chloro-substituted derivatives (in the meso-aryl rings), the electrophilic nitration occurred in position 4-.

8

Spectroscopic 1H NMR, 13C NMR and Theoretical DFT Study of Isoguanine and 8-Oxoadenine in Water and DMSO-d6 Solutions

Dybiec K., Gryff-Keller A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 11

1831-1843

EN

1Hand 13CNMRspectra of isoguanine (2-hydroxyadenine) and 8-oxoadenine inH2Oand DMSO-d6 solutions of various acidity have been interpreted using arguments based on the results of several 1D and 2D NMR experiments and theoretical DFT-based calculations. The collected data for H2O solutions can serve for identification of these compounds in body fluids during medical analysis. The 1H and 13C NMR spectra of the investigated compounds in DMSO-d6 solutions have provided information on their tautomeric forms and the mobility of their exchangeable protons.

9

Ciśnienie rozprężania węgli a skład produktów ciekłych otrzymanych w wyniku laboratoryjnego odgazowania. Cz.II. Analiza chemiczna produktów ciekłych

Tokarska A., Mianowski A.

Karbo

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2006

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Nr 1

25-27

PL

Kontynuując badania przedstawione w części I, przeprowadzono analizę składu chemicznego produktów ciekłych uzyskanych w wyniku odgazowania węgli w różnych temperaturach. Zastosowano metodę 1H NMR. Wykazano związki między ciśnieniem rozprężania węgli z tych samych kopalń a strukturą chemiczną smół

EN

As the continuation of studies presented in Part I of the paper it was carried out analysis of chemical composition of low-temperature tar and coke oven tar by 1H NMR analysis. It was proved that in the case of low-temperature tar alkyl-aromatic compounds contain long-chain and branched substituents, whereas in the case of coke oven tar substituents are smaller and less branched

10

Badanie zależności czasu relaksacji podłużnej w metodzie 1H NMR od struktury polidimetylosiloksanów i optymalizacja parametrów rejestracji widm

Jamrógiewicz Z., Mojsiewicz- Pieńkowska K., Jachowska D., Łukasiak J.

Polimery

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2005

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T. 50, nr 10

737-741

PL

Przedstawiono wyniki badań wpływu wymiarów i kształtu cząsteczek oligomerów: dimeru heksametylosiloksanu (HMDS), trimeru heksametylocyklotrisiloksanu (HMCTS), tetrameru oktametylocyklotetrasiloksanu (OMCTS) i liniowego oligodimetylosiloksanu o lepkości kinetycznej ok. 10 cSt (PDMS10), a także dwu polidimetylosiloksanów o strukturze liniowej i o lepkości ok. 300 cSt (PDMS300) bądź ok. 1000 cSt (PDMS1000) na czas relaksacji podłużnej (T1) w metodzie 1H NMR. Próbki przygotowywano rozpuszczając wymienione substancje w mieszaninie tetrachlorku węgla oraz deuterowanego benzenu. Stwierdzono, że czas T1 nie zależy w sposób istotny od stężenia analitu w próbce i jest, praktycznie biorąc, niezależny od wzajemnej proporcji stosowanych rozpuszczalników. Zaobserwowano, że wzrost długości łańcucha PDMS powoduje skrócenie T1, a cyklizacja cząsteczki nie wpływa na jego wartość. Badania wykazały, że uzyskanie wiarygodnych wyników oznaczań ilościowych PDMS wymaga zastosowania optymalnych wartości parametrów rejestracji widm, a w szczególności czasu opóźnienia (td) i czasu akwizycji danych (ta), które powinny wynosić odpowiednio 15 s i 5 s.

EN

The results of investigations of the effects of size and shape of molecules of oligomers: hexamethyldisiloxane (HMDS) dimer, octamethylcyclotetrasiloxane (OMCTS) tetramer and polydimethylsiloxane, characterized by kinetic viscosity ~10 cSt (PDMS10), as well as of two linear polydimethylsiloxanes [one of viscosity about 300 cSt (PDMS300) the other of about 1000 cSt (PDMS1000)] on longitudinal relaxation time (T1) in 1H NMR method were presented. The samples were prepared by dissolution of the substances mentioned in the mixture of carbon tetrachloride with deuterated benzene (Table 2). It was found that T1 time did not significantly depend on the analyte concentration in the sample and was practically independent on the mutual ratio of the solvents used. It was observed the increase in the chain length of PDMS caused T1 decrease while cyclization of the molecule did not influence its value (Table 2). The investigations showed that to obtain credible results of quantitative PDMS determination it was necessary to use the optimal values of spectra registration parameters, especially delay time (td) and data acquisition time (ta) which should be 15 s and 5 s, respectively.

11

Spectroscopic Studies of charge-transfer Complexation of Octathia-24-crown-8 with Iodine in Chloroform Solution

Shamsipur M., Samadi N., Irandoust M.

Polish Journal of Chemistry

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2004

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Vol.78 /nr 11-12

1979-1986

EN

The charge-transfer complexation between octathia-24-crown-8 (OT24C8) and iodine in chloroform solution was studied spectrometrically at various temperatures. The molar absorptivities and formation constants of the resulting 1:1 complex were determined. The formation of the OT24C8-I2 complex was also confirmed by 1H NMR spectrometry. The enthalpy and entropy of the charge-transfer complexation were determined from the temperature dependence of the formation constant, as Delta H graduate = -31.0 + - 0.5 kJ mol-1 and Delta S graduate = -84 + - 6 J mol-1K-1.

12

Characterization of Small Azocrown Ether Stereoisomers

Luboch E., Wagner-Wysiecka E., Kravtsov V., Kessler V.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 2

189-196

EN

The stable E- and Z-isomers of 10-membered azocrown ether have been isolated and studied by X-ray, 1H NMR and UV-Vis methods. Their structures in a solid state indicate the stretched conformation for trans-isomer and unstressed for cis-isomer. The concerted effect of azo-group _-conjugation with benzene residue and steric strain of molecular conformation results in the observed stability of isomers.

13

Synthesis and NMR study of N,N'-bis(methyl 3,4,6-tri-O-acetyl-2-deoxy-B-D-glucopyranosid-2-yl)urea and its N'-nitroso derivative

Temeriusz A., Piekarska-Bartoszewicz B., Weychert M., Wawer I.

Polish Journal of Chemistry

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1999

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vol. 73 nr 6

1011-1018

EN

N,N'-Bis(methyl 3,4,6-tri-O-acetyl-2-deoxy-b-D-glucopyranosid-2-yl)urea 1 and its N'-nitroso derivative 2 were synthesized from methyl 2-amino-3,4,6-tri-O-acetyl-2-deoxy-b-D-glucopyranoside and di(4-nitrophenyl)carbamate. The nitrosation was carried out using N2O3 in dichloromethane. The structure of compounds was analyzed by 1H, 13C, 15N NMR in CDCl3 and 13C CP MAS in the solid state. The assignments of resonances were done by COSY1H, 13C, HETCOR and the 1H, 15N2D correlation spectroscopy. Compound 1 gives one set of 1H/13C resonances in solution, but exhibits polymorphism in the solid state.

14

X-ray, IR and (1)H NMR studies of 1:1 adduct of 1,8-bis(dimethylamino)naphthalene (DMAN) and 1,1-cyclobutanedicarboxylic acid (CBDC)

Bartoszczak-Adamska E., Grech E., Jaskólski M.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

347-354

EN

The crystal and molecular structure of the title compound has been determined by X-ray analysis. This compound crystallizes in the P2-1/c space group with cell parameters: a= 9.325(2), b=15.158(3), c=14.102(3) A, beta=106.40(3)degree and with four C14H19N(+/2)xC6H7O(-/4) formula units in the unit cell. The structure contains DMANH(+) cations with a short asymmetric intramolecular N-H...N hydrogen bond (N...N 2.595(2) A) and CBDC(-) monoanions with a short intramolecular O-H...O hydrogen bond (O...) 2.412(3) A). The ionic character of he very strog (NHN)(+) and moderately strong (OHO)(-) hydrogen bonds has been derived from IR spetroscopy. The (1)H NMR spectrum measured in acetonitrile solution is similar to that in the solid state.