ماندانا زارعی

Fucoidan is a polysaccharide sulphate in brown algae which showed various biological activities. This study aimed to extract fucoidan from Cystoseira trinodis and Colpomenia sinuosa from the coast of Persian Gulf and attempted to determine its structure and characteristics. Fucoidan extracted from both species by using Cacl2 2% and water method and its structure was examined by FTIR spectrum. The extracted fucoidan by CaCl2 method had been chosen according to the yield, the chemical compounds and the FTIR spectrum and, antioxidant, anticoagulant and antibacterial activities evaluated. The 1HNMR spectrum was used for a detailed investigation of fucoidan structure. In order to determine the antioxidant activity of the extracted fucoidan, total phenol content (TPC) and DPPH free-radical scavenging activity were used. The total phenol content for C. trinodis and C. sinuosa was 8.44563 and 8.05903 (ppm gallic acid per 8 mg of fucoidan), respectively. Both of C. trinodis and C. sinuosa showed the DPPH free-radical scavenging activity, but C. trinodis had a stronger activity and its IC50 was (1.2981 mg / ml). Anticoagulant activity of Fucoidan was evaluated by using APTT and PT tests. The anticoagulant activity of both species enhanced by increasing concentrations. However, the activity of APTT C. sinuosa was higher than that of heparin in its standard concentration. Antibacterial activity of Foucheidan was investigated by plate smearing and the liquid turbidity method. The depolymerized fucoidan of C. trinodis demonstrated a great antibacterial activity at different concentrations against Escherichia coli (E.coli) and Staphyloccous aureus (S. aureus) strains, And even at the lowest concentration, no bacteria was observed growing in the plates surface. The depolymerized fucoidan of C.sinuosa had antibacterial activity only against S. aureus bacteria. A parallel activity was discerned in a liquid culture medium. And non-depolymerized fucoidan did not show any activity again