scholarly journals Extraction Improvement of the Bioactive Blue-Green Pigment “Marennine” from Diatom Haslea ostrearia’s Blue Water: A Solid-Phase Method Based on Graphitic Matrices

Marine Drugs ◽  
2020 ◽  
Vol 18 (12) ◽  
pp. 653
Author(s):  
William Bélanger ◽  
Alexandre A. Arnold ◽  
François Turcotte ◽  
Richard Saint-Louis ◽  
Jean-Sébastien Deschênes ◽  
...  
Keyword(s):  
Solid Phase ◽  
Chemical Characterization ◽  
Sulfated Polysaccharide ◽  
Added Value ◽  
Sulfated Polysaccharides ◽  
Phase Method ◽  
Blue Water ◽  
Organic Modifiers ◽  
Green Pigment ◽  
Haslea Ostrearia

The compound “marennine” is a blue–green pigment produced by the benthic microalgae Haslea ostrearia, with pathogenicity reduction activities against some bacteria and promising potential as a natural pigment in seafood industries. After decades of research, the chemical family of this compound still remains unclear, mainly because structural studies were impaired by the presence of co-extracted compounds in marennine isolates. To improve the purity of marennine extract, we developed a novel extraction method using a graphitic stationary phase, which provides various advantages over the previous procedure using tandem ultrafiltration. Our method is faster, more versatile, provides a better crude yield (66%, compared to 57% for ultrafiltration) and is amenable to upscaling with continuous photobioreactor cultivation. Our goal was to take advantage of the modulable surface properties of the graphitic matrix by optimizing its interactions with marennine. As such, the effects of organic modifiers, pH and reducing agents were studied. With this improvement on marennine purification, we achieved altogether the isolation of a fucoidan-related, sulfated polysaccharide from blue water. Characterization of the polysaccharides fraction suggests that roughly half of UV-absorbing compounds could be isolated from the marennine crude extracts. The identification of sulfated polysaccharides could be a major breakthrough for marennine purification, providing targeted isolation techniques. Likewise, the added value of Haslea ostrearia and the role of polysaccharides in previous marennine chemical characterization and bioactivity studies remain to be determined.

Peculiarities of a solid-phase method for the Al-Fe/SiO2 and Al-Co/SiO2 powder catalysts production

2019 ◽  
pp. 63-68
Author(s):  
V.A. Artyukh ◽  
◽  
V.N. Borsch ◽  
V.S. Yusupov ◽  
S.Ya. Zhuk ◽  
...  
Keyword(s):  
Solid Phase ◽  
Phase Method ◽  
Solid Phase Method ◽  
Sio2 Powder

Synthesis of hepatitis B surface antigen pre-S2 region fragments and studies on their immunogenicity

1988 ◽  
Vol 53 (11) ◽  
pp. 2952-2956 ◽  
Author(s):  
Bernard Lammek ◽  
Zbigniew Maćkiewicz ◽  
Izabela Derdowska ◽  
Hanna Świderska ◽  
Adam Nowosławski ◽  
...  
Keyword(s):  
Hepatitis B ◽  
Surface Antigen ◽  
Solid Phase ◽  
Hepatitis B Surface Antigen ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Antigenic Determinants ◽  
Phase Method ◽  
Peptide Fragments ◽  
Humoral Immune

Two peptide fragments of hepatitis B surface antigen pre-S2 region were synthesized by the solid phase method. The peptides were purified by gel filtration or ion-exchange chromatography on Sephadex SP-C-25. Both peptides induced a cellular and humoral immune response in rabbits. The results showed that fragment 14-22 of pre-S2 region contains one of the antigenic determinants.

Synthesis and biological activity of new metallocenic angiotensin II analogs

1988 ◽  
Vol 53 (11) ◽  
pp. 2914-2919 ◽  
Author(s):  
Pierrette Maes ◽  
Annie Ricouart ◽  
Emmanuel Escher ◽  
André Tartar ◽  
Christian Sergheraert
Keyword(s):  
Amino Acids ◽  
Biological Activity ◽  
Angiotensin Ii ◽  
Solid Phase ◽  
Rabbit Aorta ◽  
Phase Method ◽  
Solid Phase Method

Analogs of angiotensin II in which phenylalanine in position 8 was replaced with cymantrenylalanine or with its triphenylphosphine photosubstitution product were synthesized by the solid-phase method. On rabbit aorta strips, these peptides were found to be pure antagonists of angiotensin II. Their relative affinities are higher than most other analogs substituted in position 8 with bulky amino-acids.

Synthesis of four new V1 antagonists of arginine-vasopressin (AVP) containing new thioacids at position 1 and their vasoconstrictor activity towards isolated mesenteric arterial vessels of rats

1991 ◽  
Vol 56 (2) ◽  
pp. 491-498 ◽  
Author(s):  
Bernard Lammek ◽  
Izabela Derdowska ◽  
Tomasz M. Wierzba ◽  
Witold Juzwa
Keyword(s):  
Peptide Synthesis ◽  
Arginine Vasopressin ◽  
Solid Phase ◽  
Structural Features ◽  
Phase Method ◽  
Competitive Antagonist ◽  
Vasoconstrictor Effect ◽  
Solid Phase Method

In an attempt to determine some of the structural features in position 1 that account for V1 antagonism, four new analogues of arginine-vasopressin were synthesized and the effect of the modifications on the vasoconstrictor activity was checked using isolated mesenteric arterial vessels of rats. The protected precursors required for these analogues were synthesized by a solid phase method of peptide synthesis. One of the reported analogues, namely [1-(4-mercapto-4-tetrahydrothiopyraneacetic acid)., 2-O-methyltyrosine, 8-arginine]vasopressin appears to be a potent competitive antagonist of the vasoconstrictor effect by AVP.

scholarly journals Antimicrobial Activity and Chemical Characterization of a Non-Polar Extract of Saffron Stamens in Food Matrix

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 703
Author(s):  
Severino Zara ◽  
Giacomo L. Petretto ◽  
Alberto Mannu ◽  
Giacomo Zara ◽  
Marilena Budroni ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Fatty Acid Content ◽  
Chemical Characterization ◽  
Antimicrobial Activities ◽  
Added Value ◽  
Gas Chromatography Mass Spectrometry ◽  
Food Matrix ◽  
Bacterial Strains ◽  
By Products

The production of saffron spice generates large quantities of plant by-products: over 90% of the plant material collected is discarded, and a consideration fraction of this waste is plant stamens. This work investigated the chemical composition and the antimicrobial activities of the non-polar fraction extracted from four different saffron flower stamens. The chemical composition of ethereal extracts of the saffron stamens was qualitatively assessed by means of gas–chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) analyses. These analyses revealed ethereal extracts to possess a high polyunsaturated fatty acid content. In vitro antibacterial activity of stamen extracts showed no large differences between Gram-positive and Gram-negative bacteria in terms of minimal inhibitory concentration (MIC). In food matrix microbial analysis of the bacterial strains belonging to the main foodborne pathogen species, including Staphylococcus aureus DSM 20231, Escherichia coli DSM 30083, and Listeria monocytogenes DSM 20600, using low-fat UHT milk, revealed a statistically significant reduction in the number of cells (particularly for E. coli and S. aureus with a complete elimination of the population of the two target bacteria following incubation in diethyl ether extracts of saffron stamen (DES) at high concentrations tested, both at 37 °C and 6 °C (for 48 h and 7 days, respectively). A synergic effect was observed when the pathogens were incubated at 6 °C with DES. This work shows these by-products to be excellent sources of bioactive compounds, which could be exploited in high-added-value products, such as food, cosmetics, and drugs.

Synthesis of a 21-Residue Fragment of Human Proinsulin by the Polyamide Solid Phase Method

1981 ◽  
Vol 362 (2) ◽  
pp. 833-840 ◽  
Author(s):  
Eric ATHERTON ◽  
Willy HÜBSCHER ◽  
Robert C. SHEPPARD ◽  
Vivienne WOOLLEY
Keyword(s):  
Solid Phase ◽  
Phase Method ◽  
Human Proinsulin ◽  
Solid Phase Method

scholarly journals Fe3O4@C Nanoparticles Synthesized by In Situ Solid-Phase Method for Removal of Methylene Blue

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 330
Author(s):  
Hengli Xiang ◽  
Genkuan Ren ◽  
Yanjun Zhong ◽  
Dehua Xu ◽  
Zhiye Zhang ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Solid Phase ◽  
Raw Materials ◽  
Phase Method ◽  
Maximum Adsorption Capacity ◽  
High Catalytic Activity ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
High Concentrations

Fe3O4@C nanoparticles were prepared by an in situ, solid-phase reaction, without any precursor, using FeSO4, FeS2, and PVP K30 as raw materials. The nanoparticles were utilized to decolorize high concentrations methylene blue (MB). The results indicated that the maximum adsorption capacity of the Fe3O4@C nanoparticles was 18.52 mg/g, and that the adsorption process was exothermic. Additionally, by employing H2O2 as the initiator of a Fenton-like reaction, the removal efficiency of 100 mg/L MB reached ~99% with Fe3O4@C nanoparticles, while that of MB was only ~34% using pure Fe3O4 nanoparticles. The mechanism of H2O2 activated on the Fe3O4@C nanoparticles and the possible degradation pathways of MB are discussed. The Fe3O4@C nanoparticles retained high catalytic activity after five usage cycles. This work describes a facile method for producing Fe3O4@C nanoparticles with excellent catalytic reactivity, and therefore, represents a promising approach for the industrial production of Fe3O4@C nanoparticles for the treatment of high concentrations of dyes in wastewater.

scholarly journals Syntheses of two deacetyl-thymosin β4analogs and their anti-inflammatory effect on carrageenin-induced edema in the mouse paw

2001 ◽  
Vol 10 (2) ◽  
pp. 89-92 ◽  
Author(s):  
T. Abiko ◽  
R. Ogawa
Keyword(s):  
Marked Reduction ◽  
Solid Phase ◽  
The Other ◽  
Para Position ◽  
Phase Method ◽  
Antiinflammatory Effect ◽  
Solid Phase Method ◽  
Anti Inflammatory ◽  
Inflammatory Effect

Two {Met(0)6}deacetyl-thymosin β4analogs containing Phe(4F) or Tyr(Me) at position 12 were synthesized by the manual solid-phase method, and their anti-inflammatory effect on carrageenin-induced edema in the mouse paw was studied. Fluorination of the para-position of Phe12resulted in a marked antiinflammatory effect on carrageenin-induced edema in the mouse paw compared with that of our synthetic {Met(0)6}deacetyl-thymosin β4, but the other analog, {Met(0)6, Tyr(Me)12}deacetyl-thymosin β4, showed a marked reduction of the anti-inflammatory effect.

The Research of Silica-Coated Chromium Oxide Green Pigment Prepared by Liquid Phase Method

2011 ◽  
Vol 84-85 ◽  
pp. 514-518
Author(s):  
Hong Yan Zhang ◽  
Jin Hua Wang ◽  
Li Fang Zhang ◽  
Li Li Wang
Keyword(s):  
Liquid Phase ◽  
Experimental Method ◽  
Chromium Oxide ◽  
Particle Surface ◽  
Tetraethyl Orthosilicate ◽  
Hydrolysis Reaction ◽  
Phase Method ◽  
Green Pigment ◽  
Coated Particle ◽  
Liquid Phase Method

This paper is researched on SiO2-coated Cr2O3 for the hydrolysis reaction of tetraethyl orthosilicate. The influences of precursors, solid contents of suspension and Si ratio of water on coated particle surface are investigated. The products are characterized and the conclusion shows that the experimental method is feasible.

The Gas-Solid-Phase 2,5-Dioxopiperazine Synthesis. Cyclization of Vaporous Dipeptides on Silica Surface

1994 ◽  
Vol 59 (2) ◽  
pp. 461-466 ◽  
Author(s):  
Vladimir A. Basiuk ◽  
Taras Yu. Gromovoy
Keyword(s):  
Silica Surface ◽  
Solid Phase ◽  
Phase Method ◽  
Solid Phase Method

The "gas solid-phase" method is used for the preparation of both symmetric and asymmetric 2,5-dioxopiperazines via cyclization of vaporous linear dipeptides in the presence of silica.

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