Structural Characteristics and Cytotoxic activity of Polysaccharide Extracted from Green Seaweed Caulerpa torta

In this work, hot water extraction was applied to isolate a polysaccharide from green seaweed Caulerpa torta, the extraction yield was 3.4% of dried seaweed weight. The structural characteristics and cytotoxic effects on three human cancer cell lines of the polysaccharide were investigated. The results showed that the polysaccharide consisted of galactose, glucose, xylose and mannose in a molar ratio of 1.00: 0.74: 0.21: 0.0.21, with a molecular weight of 107 kDa. In addition, it contained sulfate groups, which is approximately 15.34%w. The polysaccharide showed a significant cytotoxic activity against thyroid cancer - 8505C (IC50 55.55±1.84 µg/ml), colon cancer - HT-29 (IC50 57.26±2.06 µg/ml) and cervical cancer - Hela (IC50 54.79 ±3.22 µg/ml).