Sulfation of extracellular polysaccharides of red microalgae: preparation, characterization and properties

Geresh, Shimona; Mamontov, Anna; Weinstein, Jacob J.

doi:10.1016/s0165-022x(01)00185-3

Cited by 85 publications

(46 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…and Porphyridium sp. were well depicted as viscous exopolysaccharides producers [14,18], although, there was an ambivalence concerning the abundant literature describing exopolymers from Arthrospira platensis [16,29]. Effectively, no increase of apparent viscosity of culture media was detected after incubation of Arthrospira platensis PCC 8005 during 168 h. When Arthrospira platensis was grown in microplates, it was obvious that a spot remained present in the bottom of wells after 168 h of incubation, meaning that Arthrospira platensis was not able to adhere on a surface or to increase the viscosity in the Zarrouk medium (Fig.…”

Section: Resultsmentioning

confidence: 99%

A new tool to detect high viscous exopolymers from microalgae

Badel¹,

Callet²,

Laroche³

et al. 2010

J Ind Microbiol Biotechnol

View full text Add to dashboard Cite

Microalgae are microorganisms often surrounded by a slime layer made of secreted polymeric substances sometimes including polysaccharides. These polysaccharides, weakly described in the literature, can constitute value-added molecules in several industrial areas. The aim of this article is to show that a new tool, the BioFilm Ring Test®, can be used to detect viscous microalgal exopolymers. Two red microalgal strains (Rhodella violacea and Porphyridium purpureum), one cyanobacterium (Arthrospira platensis) and their excreted polymeric fractions were studied. R. violacea and P. purpureum induced a positive response with the BioFilm Ring Test® contrary to A. platensis. Finally, the understanding of the fractions viscosity involvement in the BRT response was performed by a rheological study.

show abstract

Section: Resultsmentioning

confidence: 99%

A new tool to detect high viscous exopolymers from microalgae

Badel¹,

Callet²,

Laroche³

et al. 2010

J Ind Microbiol Biotechnol

View full text Add to dashboard Cite

show abstract

“…The higher negative charge induces more repulsion between chains and a more expanded macromolecular conformation. However, Geresh et al 29 found for sulfated extracellular polysaccharides that the viscosity of sulfated products was lower than that of the starting material, even with no evidence of degradation.…”

Section: Rheological Studiesmentioning

confidence: 98%

“…An increase in the amount of CSA promoted a significant decrease in the sulfation yield. The comparison of the reaction yields of cashew gum and of other gum derivatives obtained using similar methodology was not possible, since this information was not available in either of the reports by O'Neill 17 and Ono et al 18 The apparent yields of more than 100% were reported by Geresh et al 29 in the sulfation of extracellular polysaccharides of red microalgae. In this case, although not specified, the yields were calculated as the mass of sulfated product in relation to the initial mass of polysaccharide.…”

Section: Effect Of Chlorosulfonic Acid Concentration On Yield and Degmentioning

confidence: 99%

Preparation and characterization of a chemically sulfated cashew gum polysaccharide

Neto¹,

Maciel²,

Cunha³

et al. 2011

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

A goma do cajueiro (GC) foi sulfatada em piridina:formamida usando ácido clorossulfônico como reagente. A confirmação da sulfatação foi obtida por espectroscopia no infravermelho com transformada de Fourier (FTIR) pelo aparecimento da frequência de vibração em 1259 cm -1 devido ao estiramento assimétrico S=O. Os graus de sulfatação foram de 0,02, 0,24 e 0,88, determinados pela percentagem de enxofre. Os dados de ressonância magnética nuclear (RMN) 1D e 2D mostram que a sulfatação ocorreu nos carbonos primários do polissacarídeo. Um aumento de no mínimo 4% na viscosidade da solução foi observado após a sulfatação. Análise termogravimétrica (TGA) indica que o derivado é estável até cerca de 200 ºC. A comparação entre os derivados sulfatados e carboximetilados foi feita no intuito de verificar a possibilidade de formação de complexos polieletrolíticos, já realizada com os carboximetilados.Cashew gum (CG) was sulfated in pyridine:formamide using chlorosulfonic acid as the reagent. Confirmation of sulfation was obtained by Fourier transform infrared (FTIR) spectroscopy through the presence of an asymmetrical S=O stretching vibration at 1259 cm -1 . The degrees of substitution were 0.02, 0.24 and 0.88 determined from the sulfur percentage. 1D and 2D nuclear magnetic resonance (NMR) data showed that the sulfation occurred at primary carbons. An increase of at least 4% of the solution viscosity was observed due to sulfation. The thermal gravimetric curves (TGA) indicate that the derivatives are stable up to ca. 200 °C. The sulfated CG is compared to carboxymethylated CG in order to verify the possibility of the use of the former in the preparation of polyelectrolyte complexes; the latter is already being used for this application.

show abstract

“…All, Porphyridium sp., P. cruentum and D. grisea PShs have been reported to be potent antioxidants (11,37,39). in a series of experiments, samples of sulfated polysaccharides and samples of natural polysaccharides from red microalgae were found to inhibit the cell growth of FD (early myeloid cell line) and el-4 and 24-1 t-lymphoma cell lines (18). the anticancer activity of these red microalgal PShs seems to be promising, but has not been intensively studied yet.…”

Section: Introductionmentioning

confidence: 99%