In vitro Anticancer potential of Laminarin and Fucoidan from Brown seaweeds

Abstract Marine seaweeds are cultivated and consumed in China, Japan, Korea, and South Asian countries. Brown seaweeds are rich sources of polysaccharides such as Laminarin and Fucoidan. In the present study, both the laminarin and fucoidan were isolated and the obtained yield was higher in PP (4.36%) and STM (2.32%) respectively. Carbohydrate content in laminarin and fucoidan was 86.91% and 87.36%, whereas sulphate content in fucoidan was 20.68%. Glucose and mannose were the major monosaccharide units in laminarin, similarly, fucose, galactose, and xylose in fucoidan (STM). FT-IR down peaks represent the carbohydrate of laminarin and fucoidan except, 1219 cm-1, and 843 cm-1, illustrating the sulphate groups of fucoidan. The molecular weight of laminarin and fucoidan was 3 to 5 kDa, and 2 to 6 kDa respectively. Both polysaccharides showed no cytotoxicity on Vero normal cells, whereas, they were cytotoxic to the human colon (HT-29), and liver cancer cells (Hep G2) with IC50 values of 57 ± 1.2 µg/mL and 24.4 ± 1.5 µg/mL. AO/EB assay significantly resulted in apoptosis and necrosis upon laminarin and fucoidan treatment. DNA fragmentation results support necrotic cancer cell death. Therefore, laminarin and fucoidan from PP and STM were potential bioactive compounds for cancer therapy.