In Vitro Antiproliferative Activity of Fucoidans Extracted From Sargassum natans and Sargassum fluitans in the HeLa Cell Line.

This paper presents an analysis of the polyphenol content, antioxidant capacity, and antiproliferative activity of fucoidans extracted from Sargassum natans and Sargassum fluitans. The results obtained indicated a high total polyphenol content (113 ± 2.3 mg GAE/g), which is probably associated with great antioxidant capacity. Antioxidant activity determined by the DPPH and FRAP methods resulted in 42.21% ± 0.864% inhibition and 1911 ± 71 mM TE/g, respectively. The degree of sulfation for the extracted fucoidans was found to be, using a turbidimetric method with BaCl2, at 13.2% for S. natans and 15.6% for S. fluitans. In addition, intrinsic viscosity determination allowed molecular weights to be estimated using the Mark-Houwink equation as 26.2 and 18.7 kDa for S. natans and S. fluitans, respectively. The antiproliferative properties of fucoidans extracted from Sargassum were evaluated through the MTT assay on HeLa cervical cancer cells. The study revealed a marked reduction in cell proliferation, most notably at higher concentrations (4000 μg/mL), where the inhibition rate reached 90.80%, with an IC50 value of 1277.79 μg/mL. These findings emphasize the strong antiproliferative effects of Sargassum-derived fucoidans, believed to function through pathways such as apoptosis induction, cell cycle modulation, and suppression of cellular growth. The observed biological activity appears strongly tied to structural characteristics like sulfation patterns and molecular weight, which are critical determinants of fucoidan functionality. This aligns with earlier research highlighting the antitumor and antioxidant properties of fucoidans. Moving forward, in vivo studies will be essential to validate their safety profile and therapeutic potential in animal models. Furthermore, detailed mechanistic investigations should be prioritized to uncover the pathways driving their anticancer effects.