Effect of fucoidan from Turbinaria conoides on human lung adenocarcinoma epithelial (A549) cells

Fucoidan was purified from seaweed, Turbinaria conoides. Isolated fragments were characterized with NMR (13C, 1H), Gas Chromatography–Mass Spectronomy (GC–MS) and HPLC analysis. The autohydrolysate of fucoidans consisted of sulfated fuco-oligosaccharides having the backbone of α-(1, 3)-linked fuco-pyranose derivatives and minor components of galactose, glucose, mannose and xylose sugars. Fucoidan induced a dose-dependent reduction in cell survival of lung cancer A549 cells by MTT assay (GI50, 75 μg/mL). However, it was not cytotoxic to a non-tumorigenic human keratinocyte cell line of skin tissue (HaCaT) (GI50 > 1.0 mg/mL). The apoptotic cells in fucoidan-treated A549 cells were visualized by laser confocal microscopy and cell cycle analysis showed induction of G0/G1 phase arrest of the cell progression cycle. Further, CFSE labeling and flow cytometry highlighted that fucoidan significantly (P < 0.05) inhibited the proliferation rate of A549 cells by up to 2-fold compared with the control cells. It is concluded that fucoidan has the potential to act as an anti-proliferative agent on lung carcinoma (A549) cells