Two new exopolysaccharides from a thermophilic bacterium Geobacillus sp. WSUCF1: Characterization and bioactivities

Wang, Jia; Salem, David R.; Sani, Rajesh K.

doi:10.1016/j.nbt.2020.11.004

Cited by 27 publications

(15 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Samples F-1 100 and F-1 30 had the lowest weight loss values at this temperature range (10 and 8%, respectively), suggesting they had lower contents of adsorbed water compared to the samples obtained by Methods 2 and 3 that displayed the same weight loss (12%). The second and more significant weight loss, similar to all samples (41–43%), occurring between 203 and 344 °C, is the degradation of FucoPol’s saccharide chain, namely, the depolymerization and the dehydration of saccharide rings [ 47 ]. The T deg of the samples was determined to be in the range 261–263 °C, thus showing no significant differences among the samples extracted by each of the tested methods.…”

Section: Resultsmentioning

confidence: 99%

Extraction of the Bacterial Extracellular Polysaccharide FucoPol by Membrane-Based Methods: Efficiency and Impact on Biopolymer Properties

et al. 2022

View full text Add to dashboard Cite

In this study, membrane-based methods were evaluated for the recovery of FucoPol, the fucose-rich exopolysaccharide (EPS) secreted by the bacterium Enterobacter A47, aiming at reducing the total water consumption and extraction time, while keeping a high product recovery, thus making the downstream procedure more sustainable and cost-effective. The optimized method involved ultrafiltration of the cell-free supernatant using a 30 kDa molecular weight cut-off (MWCO) membrane that allowed for a 37% reduction of the total water consumption and a 55% reduction of the extraction time, compared to the previously used method (diafiltration-ultrafiltration with a 100 kDa MWCO membrane). This change in the downstream procedure improved the product’s recovery (around 10% increase) and its purity, evidenced by the lower protein (8.2 wt%) and inorganic salts (4.0 wt%) contents of the samples (compared to 9.3 and 8.6 wt%, respectively, for the previously used method), without impacting FucoPol’s sugar and acyl groups composition, molecular mass distribution or thermal degradation profile. The biopolymer’s emulsion-forming and stabilizing capacity was also not affected (emulsification activity (EA) with olive oil, at a 2:3 ratio, of 98 ± 0% for all samples), while the rheological properties were improved (the zero-shear viscosity increased from 8.89 ± 0.62 Pa·s to 17.40 ± 0.04 Pa·s), which can be assigned to the higher purity degree of the extracted samples. These findings demonstrate a significant improvement in the downstream procedure raising FucoPol’s recovery, while reducing water consumption and operation time, key criteria in terms of process economic and environmental sustainability. Moreover, those changes improved the biopolymer’s rheological properties, known to significantly impact FucoPol’s utilization in cosmetic, pharmaceutical or food products.

show abstract

Section: Resultsmentioning

confidence: 99%

Extraction of the Bacterial Extracellular Polysaccharide FucoPol by Membrane-Based Methods: Efficiency and Impact on Biopolymer Properties

et al. 2022

View full text Add to dashboard Cite

show abstract

“…In the first degradation step, occurring between 40 and around 150–160 °C, similar weight losses were found for both samples (11–13%), which corresponded to the loss of the water adsorbed to the polysaccharides due to their hygroscopic nature [ 2 ]. The second and main degradation step occurred between 196 and 320 °C, with weight losses of around 41% for both samples, which can be attributed to the thermal depolymerization of the polysaccharides’ chains and the dehydration of the saccharide rings [ 34 ]. The T deg value was similar for both FucoPol (259 °C) and d-FucoPol (256 °C), thus confirming no significant differences between them.…”

Section: Resultsmentioning

confidence: 99%

Deacetylation and Desuccinylation of the Fucose-Rich Polysaccharide Fucopol: Impact on Biopolymer Physical and Chemical Properties

Baptista¹,

Araújo

Concórdio‐Reis³

et al. 2022

Molecules

View full text Add to dashboard Cite

FucoPol is an acylated polysaccharide with demonstrated valuable functional properties that include a shear thinning fluid behaviour, a film-forming capacity, and an emulsion forming and stabilizing capacity. In this study, the different conditions (concentration, temperature, and time) for alkaline treatment were investigated to deacylate FucoPol. Complete deacetylation and desuccinylation was achieved with 0.02 M NaOH, at 60 °C for 15 min, with no significant impact on the biopolymer’s sugar composition, pyruvate content, and molecular mass distribution. FucoPol depyruvylation by acid hydrolysis was attempted, but it resulted in a very low polymer recovery. The effect of the ionic strength, pH, and temperature on the deacetylated/desuccinylated polysaccharide, d-FucoPol, was evaluated, as well as its emulsion and film-forming capacity. d-FucoPol aqueous solutions maintained the shear thinning behaviour characteristic of FucoPol, but the apparent viscosity decreased significantly. Moreover, contrary to FucoPol, whose solutions were not affected by the media’s ionic strength, the d-FucoPol solutions had a significantly higher apparent viscosity for a higher ionic strength. On the other hand, the d-FucoPol solutions were not affected by the pH in the range of 3.6–11.5, while FucoPol had a decreased viscosity for acidic pH values and for a pH above 10.5. Although d-FucoPol displayed an emulsification activity for olive oil similar to that of FucoPol (98 ± 0%) for an oil-to-water ratio of 2:3, the emulsions were less viscous. The d-FucoPol films were flexible, with a higher Young′s modulus (798 ± 152 MPa), a stress at the break (22.5 ± 2.5 MPa), and an elongation at the break (9.3 ± 0.7%) than FucoPol (458 ± 32 MPa, 15.5 ± 0.3 MPa and 8.1 ± 1.0%, respectively). Given these findings, d-FucoPol arises as a promising novel biopolymer, with distinctive properties that may render it useful for utilization as a suspending or emulsifier agent, and as a barrier in coatings and packaging films.

show abstract

“…The percentage crystallinity was found to be higher than the EPS from Leuconostoc lactis KC117496 (33.4%) (Saravanan and Shetty, 2016). Crystallization of EPS can be hampered by the uneven arrangement of monomers and their composition (Wang et al, 2021).…”

Section: Xrd Analysis Of Eps-om03mentioning

confidence: 99%

Exopolysaccharide from the mice ovarian bacterium Bacillus velezensis OM03 triggers caspase-3-dependent apoptosis in ovarian cancer cells

Chirakkara¹,

Abraham²

2023

J App Pharm Sc

View full text Add to dashboard Cite

Exopolysaccharides (EPS) were isolated from mice ovarian microflora Bacillus velezensis OM03 to investigate their chemical properties and cytotoxic potential against human ovarian carcinoma cell lines PA-1 and SKOV-3. The structural analysis of EPS from OM03 using Fourier Transform Infra-Red spectroscopy, X-ray diffraction, Scanning Electron Microscopy, and Gas chromatography-Mass revealed that it is a novel heteropolysaccharide made of glucose and mannose units connected with α-1,4 and β-1,4 bonds. Attractively, the EPS inhibited the proliferation of SKOV-3 and PA-1 cancer cells in a concentration-dependent manner, with IC 50 values of 620 and 238 µg/ml, respectively, according to 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tests. Moreover, EPS-OM03 caused DNA fragmentation in PA-1 cell lines and boosted the expression of active caspase-3, both of which triggered apoptosis. Furthermore, the experiment with the chick embryo chorioallantoic membrane demonstrated that treatment with EPS-OM03 exhibits an in vivo antiangiogenic effect with an IC 50 of 146 µg/ml. In conclusion, our work offers scientific support for the development and use of pharmaceuticals derived from the microbiome, and it suggests that the EPS from B. velezensis OM03 may be a lead molecule in the treatment of ovarian cancer.

show abstract

Two new exopolysaccharides from a thermophilic bacterium Geobacillus sp. WSUCF1: Characterization and bioactivities

Cited by 27 publications

References 56 publications

Extraction of the Bacterial Extracellular Polysaccharide FucoPol by Membrane-Based Methods: Efficiency and Impact on Biopolymer Properties

Extraction of the Bacterial Extracellular Polysaccharide FucoPol by Membrane-Based Methods: Efficiency and Impact on Biopolymer Properties

Deacetylation and Desuccinylation of the Fucose-Rich Polysaccharide Fucopol: Impact on Biopolymer Physical and Chemical Properties

Exopolysaccharide from the mice ovarian bacterium Bacillus velezensis OM03 triggers caspase-3-dependent apoptosis in ovarian cancer cells

Contact Info

Product

Resources

About