Antitumor and immunostimulating sulfated polysaccharides from brown algae Dictyota caribaea

Abstract Sulfated polysaccharides (SP) are a complex group of bioactive molecules able to inhibit tumor growth. SP increase the effectiveness of chemotherapy and reduce some side effects. Brown algae produce SP with several biological activities including antitumor. This work aimed to investigate the antitumor effect of SP from the brown algae Dictyota caribaea (Dc-SP). The chemical analyses demonstrated Dc-SP composition was mainly hexose, uronic acid, and sulfate. Dc-SP did not exhibit cytotoxicity against tumor cells in vitro. However, Dc-SP-treated mice with 25 and 50 mg/kg/day depicted Sarcoma 180 tumor growth inhibition of 40% (p