Evaluation of antioxidant and anti-cancer activities of Fucose-containing sulfated polysaccharide (FCSPs) from Hawaiian Marine Algae

Abstract

Fucoidan is a group of sulfated polysaccharides isolated from marine algae. Fucoidan exhibits a variety of biological activities which are related to their chemically distinct sulfated fucose backbone. The structures of select fucoidans vary by species, and the structure and bioactivity remains unclear. The fucoidan of Padina sp., Asparagopsis taxiformus, and Nishime Kombu were extracted using four different methods using water at different temperatures. Method 2 gave the highest yield of fucoidan by 1H NMR analysis, whereas method 4 yielded FCSPs with anti-cancer activities. The crude fucoidan of Padina sp. was further purified using ion-exchange chromatography, resulting in the highest yield of fucoidan at 2.5 M NaCl. Cell viability was determined using sulforhodamine B (SRB) assay in five cancer cells (LNCap, PC-3, MCF-7, Caco-2, and LU-1). Both standard and Kombu-extracted fucoidan showed no effects on prostate (LNCaP and PC-3), and breast (MCF-7) cancer cells, but inhibited the growth of colon (Caco-2) and lung (LU-1) cancer cells by 43-74% at concentrations in the range of 50-400 µg/mL. These crude FCSPs also exhibited antioxidant activity. The FRAP values of Nishime Kombu, U-Fn, and Fucoidan Force, were 586.44 ± 107 µM/mg extract, 2922.38 ± 981 µM/mg, and 4212.03 ± 745 µM/mg, respectively.