An Unfractionated Fucoidan from Ascophyllum nodosum: Extraction, Characterization, and Apoptotic Effects in Vitro

Abstract

An unfractionated fucoidan was extracted from the brown alga Ascophyllum nodosum. Extraction of fucoidan from seaweed was carried out using an innovative low-chemical process. A combinational approach involving compositional analysis, HPAEC, IR analysis, GPC, and NMR was employed to elucidate the composition and structure of an unfractionated fucoidan from A. nodosum. This fucoidan is composed mainly of fucose (52.1%), and also galactose (6.1%), glucose (21.3%), and xylose (16.5%). Sulfate content was determined to be 19%. GPC data indicated a polydisperse fucoidan containing two main size fractions (47 and 420 kDa). NMR analyses revealed a fucoidan displaying broad, complex signals as expected for such a high molecular weight and heterogeneous polymer with resonances consistent with a fucoidan isolated previously from A. nodosum. The effects of fucoidan on the apoptosis of human colon carcinoma cells and fucoidan-mediated signaling pathways were also investigated. Fucoidan decreased cell viability and induced apoptosis of HCT116 colon carcinoma cells. Fucoidan treatment of HCT116 cells induced activation of caspases-9 and -3 and the cleavage of PARP, led to apoptotic morphological changes, and altered mitochondrial membrane permeability. These results detail the structure and biological activity of an unfractionated fucoidan from A. nodosum.

Sargassum Fusiforme Polysaccharide SFP-F2 Activates the NF-κB Signaling Pathway via CD14/IKK and P38 Axes in RAW264.7 Cells

“…The absorption peak at 1051 cm −1 could possibly be contributed by the C3-O-C6 bridge of the anhydrogalactose residue [12]. The absorption at 817 cm −1 suggested the presence of sulfate groups at the equatorial C-2 and C-3 positions [13]. The band at 580 cm −1 suggested the obvious asymmetric deformation absorption of O-S-O, which is characteristic of sulfate content and the substitution position.…”

The Identification of a SIRT6 Activator from Brown Algae Fucus distichus

“…A significant increase in deacetylation activity was observed in a dose-dependent manner using the HPLC-guided deacetylation-based assay as well Western blot analysis. The commercial fucoidan, from F. vesiculosus , has been reported to contain fucose (>50%), galactose (6%), glucose (20%), mannose, xylose (15%), uronic acid, glucosamine, and sulfate [28]. None of these monosaccharides introduced any SIRT6 activity at a concentration up to 300 μM (data not shown), indicating that the activity is most likely due to the sulfated fucose.…”

“…In addition, heparin and heparan sulfate proteoglycans have been reported to be potent inhibitors of HAT (Histone acetyltransferases) activity [34]. Further, fucoidan has been indicated to play a role in apoptosis [28,35,36]. In one study, it induced the cleavage of PARP (poly ADP ribose polymerase) to the 89 kDa polypeptide, suggesting that caspases were involved in the fucoidan-mediated apoptosis [37].…”

“…Furthermore, in a study in rabbits investigated fucoidan injected intramuscular (i.m. )-induced apoptosis in isolated lymphoma cell lines in vitro [28]. Similarly, SIRT6 overexpression has been demonstrated to induce apoptosis in cancer cells and not in normal cells [8].…”

Therapeutic importance of sulfated polysaccharides from seaweeds: updating the recent findings

“…An unfractionated fucoidan was extracted from the brown alga Ascophyllum nodosum and its effect on the apoptosis of human HCT116 colon carcinoma cells was studied and the signaling pathways involved were investigated. Fucoidan decreased cell viability and induced apoptosis of the carcinoma cells, through activation of caspases 9 and 3 and the cleavage of PARP (Foley et al 2011). Haneji et al (2005) examined the effect of fucoidan from the brown seaweed Cladosiphon okamuranus Tokida against an incurable form of cancer, the adult T-cell leukemia (ATL).…”